Hydrogen from biomass – Present scenario and future prospects

ArticleinInternational Journal of Hydrogen Energy 35(14):7416-7426 · July 2010with 246 Reads 
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Abstract
Hydrogen is considered in many countries to be an important alternative energy vector and a bridge to a sustainable energy future. Hydrogen is not an energy source. It is not primary energy existing freely in nature. Hydrogen is a secondary form of energy that has to be manufactured like electricity. It is an energy carrier. Hydrogen can be produced from a wide variety of primary energy sources and different production technologies. About half of all the hydrogen as currently produced is obtained from thermo catalytic and gasification processes using natural gas as a starting material, heavy oils and naphtha make up the next largest source, followed by coal. Currently, much research has been focused on sustainable and environmental friendly energy from biomass to replace conventional fossil fuels. Biomass can be considered as the best option and has the largest potential, which meets energy requirements and could insure fuel supply in the future. Biomass and biomass-derived fuels can be used to produce hydrogen sustainably. Biomass gasification offers the earliest and most economical route for the production of renewable hydrogen.

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  • ... The recent development in hydrogen economy that utilizes hydrogen as fuel has shown great potential in the advancement of renewable biomass energy resources. This effort is motivated by the current dependency on non-renewable fossil fuels to produce hydrogen, such as petroleum derivatives and natural gas [1], which are neither reasonable nor sustainable in the view of an economic standpoint [2]. ...
    ... Thus, biomass is promising to be used as feedstock resources for hydrogen production. In general, hydrogen may be produced from biomass via two routes: (1) direct production routes and (2) conversion of storable intermediates [1,3]. The first route may include thermochemical gasification, pyrolysis, and anaerobic digestion [1]. ...
    ... In general, hydrogen may be produced from biomass via two routes: (1) direct production routes and (2) conversion of storable intermediates [1,3]. The first route may include thermochemical gasification, pyrolysis, and anaerobic digestion [1]. Meanwhile, the second route may include the steam reforming process of bio-oil, which is produced from biomass pyrolysis [3]. ...
    Article
    Steam reforming of biomass pyrolysis oil or bio-oil derivatives is one of the attractive approaches for hydrogen production. The current research focused on the development of promising catalysts with favorable catalytic activity and high coke resistance. Noble metal such as Rh has been proven to achieve promising reforming reaction efficiencies. However, Ni has attracted considerable attention owing to its stability, cost effectiveness, and good activity in breaking C–C and C–H bonds. Nevertheless, Ni-based catalysts have serious carbon deposition problems arising from chemical poisoning, metal sintering, and poor metal dispersion. This paper attempted to review the current trends in catalyst development considering the aspects of supports, metals, and promoters as an effort to find possible solutions for the limitations of Ni-based catalysts. The present review also covered the current understanding on the reaction mechanisms as well as the future prospects in the field of steam reforming catalysts.
  • ... Fossil fuels, which are theoretically finite, supply the majority of energy in the world, but as they are produced, transported, or used they can negatively impact the environment by releasing harmful gases during the combustion process [1]. ...
    ... Hydrogen also has a high energy density and heating value (122 kJ/kg), which results in a high flame speed and octane number. Since water is the only byproduct produced in the burning process (H 2 þ 0:5O 2 /H 2 O) it doesn't harm the environment and impact Global Warming [1,12]. It isn't an energy form that exists freely in nature, but rather a second form of energy that needs to be produced [1]. ...
    ... Since water is the only byproduct produced in the burning process (H 2 þ 0:5O 2 /H 2 O) it doesn't harm the environment and impact Global Warming [1,12]. It isn't an energy form that exists freely in nature, but rather a second form of energy that needs to be produced [1]. Hydrogen can be used directly as fuel in fuel-cells and internal combustion engines. ...
    Article
    Producer gas is a renewable fuel obtained from gasification processes. This fuel may be burned directly in furnaces to supply thermal demands, or used to run internal combustion engines or gas turbines. The characteristics of producer gas have been studied by various authors, however, most studies generally use mixtures of synthetic gases to represent Producer Gas. The main goal of this study is to evaluate the laminar flame velocity of Producer Gas obtained from gasifying eucalyptus wood in a two-stage downdraft gasifier using the Bunsen burner method and the Schlieren image visualization technique to register the profile of the flame. The Producer Gas volume fractions that were used in the tests were 20%, 16%, and 1.8% for CO, H2, and CH4, respectively. This resulted in a 4.9 MJ/Nm³ lower heating value. The registered laminar flame velocity at the stoichiometric point under optimal conditions was 0.33 m/s. The tests were carried out at standard atmospheric pressure and atmospheric temperature. The results were compared to studies of other authors, and this study shows that fractions of Hydrogen (H2) and Carbon Monoxide (CO) in the Producer Gas result in increased laminar flame velocities, while fractions Nitrogen (N2) and Carbon Dioxide (CO2) result in reduced flame velocities.
  • ... Depending on the use of these resources, it is necessary to have alternative energy production routes due to the increasing environmental impacts of gas emissions. 1 The synthesis gas produced by partial oxidation of the biomass usually comprises H 2 , CO, CO 2 , and CH 4 ; diverse pollutants such as tar (black viscous liquid) and ash occur as by-products of gasification. 2 The abovementioned hydrogen gas is considered as a clean energy option to reduce the dependence on petroleum and covers a huge amount of the world energy requirement. ...
    ... 2 The abovementioned hydrogen gas is considered as a clean energy option to reduce the dependence on petroleum and covers a huge amount of the world energy requirement. 3,4 While natural gas is mainly used in hydrogen production, nowadays, by means of fossil fuel reforming, approximately 90% of total production is obtained. 5 Gasification is also a process that can produce hydrogen-rich gas fuels and can use the resulting gas in the Fischer-Tropsch process, fuel cell systems, and in methanol synthesis reactions. ...
    Article
    In this study, artificial neural networks (ANNs) and a nonlinear autoregressive exogenous (NARX) neural network model were employed in order to model a fixed bed downdraft gasification. The relation between the feature group and the regression performance was investigated. First, feature group consists of the equivalence ratio (ER), air flow rate (AF), and temperature distribution (T0-T5) obtained from the fixed bed downdraft gasifiers, while the second group includes ultimate and proximate values of biomasses, ER, AF, and the reduction temperature (T0). Models constructed to predict the syngas composition (H 2 , CO 2 , CO, CH 4) and calorific value. Experimental gasification data that involve 3831 data samples that belong to pinecone and wood pellet were used for training the ANNs. Different ANN architecture and NARX time series model have been constructed to examine the prediction accuracy of the models. The results of the ANN models were consistent with the experimental data (R 2 > 0.99). The overall score of NARX time series networks is found to be higher than other architecture types. A successful method is proposed to reduce the number of features, and the effect of the features on the prediction capability was examined by calculating the relative importance index using the Garson's equation.
  • ... Additionally, hydrogen is a principal component of many chemical and fuel products such as ammonia, methane, urea, ethanol, etc [8,9]. Due to these reasons, further research in the domain of hydrogen production is necessary so that future technology will meet these requirements [10]. Moreover, the hydrogen is useful in fuel cell applications and many integrated processes have been investigated for hydrogen production processes with fuel cells [11e13]. ...
    ... Many countries have started to determine the value of the hydrogen economy and make efforts to take significant steps towards a hydrogen economy and planned the polices and methods as reviews by many researchers, such as, for Malaysia [15], Pakistan [16], Taiwan [17], China [18], Portugal [19], and Canada [20], etc. The value of the hydrogen economy was 107 billion $ in 2016 [21], 115.25 billion $ in 2017 and is expected to rise to 154.74 billion $ by 2022 [10]. In a recent research report, world hydrogen demand has been reported as 50 million metric tons/year or 45 billion kg/year in 2006 and has been increasing at the rate of 10% annually [11]. ...
    Article
    Hydrogen is a zero-emission green fuel containing sufficient energy potentially suitable for electricity generation. Currently, large quantities of hydrogen are produced using classical fossil fuels. Nevertheless, the finite quantities of these resources have compelled the global community to look into using more sustainable and environmentally friendly resources such as bio-based waste. There are several approaches, to convert biomass to hydrogen, among which the thermochemical and biological processes are considered as the most important ones. The aim of this review paper is twofold, namely, (a) to evaluate hydrogen production and biomass processing methods to give a better insight into their potential merits and identify gaps for sustainable hydrogen generation, and (b) to evaluate current and future opportunities in membrane technology for hydrogen separation and purification from biomass processing. By fulfilling these gaps, the objectives of economical, sustainable, and environmentally-friendly resources for hydrogen production and separation can be recommended.
  • ... The greatest concern of the global population in today's world is the environmental pollution.This is mainly taking place due to the rapid growth of population and their demands, giving rise to rapid utilization of resources and the industrialization.The rate of usage of these non-renewable resources is resulting in the shortage of the conventional resources such as reserves of coal, petroleum and natural gas [1]. The increase in the utilisation of these non-renewable resources has led to the release of large amount of CO2 and other harmful gases in the environment, which is the noble cause of various environmental pollutions [2]. ...
    ... The bio-hydrogen gas is the production of gas as an alternative source of energy for the usage in our day-to-day life activities as a fuel from the biological sources such as the feedstocks like bioenergy crops and organic waste from processing of wood and agricultural wastes [1]. The matter used for the generation process are the renewable sources of energy by the action of microbes. ...
    Conference Paper
    The greatest concern for the world today is the environmental pollutions that is mainly taking place due to the rapid utilization of natural resources and industrialization. The most common root for this is the release of harmful gases by the combustion of fossil fuels, which causes various environmental issues. There is need to overcome these issues by developing advance and alternate energy sources, which can mimic this issues without any impact in the surroundings. Although the conventional fuels are depleting at a higher rate today like reserves of oil, coal and natural gas, therefore research is carried out for the sustainable environment for future generations. However, hydrogen assures to be a potential clean, renewable and environmental friendly energy source because of its easy conversion accessibility to electricity by fuel cells and it does not involve any emission of greenhouse gases like CO2, which are released from the combustion as a clean fuel. Biological hydrogen production generally can be carried out by two mechanisms—the fermentation and photo biological production. Photo biological hydrogen production has the advantage that utilizes solar radiation to run the operation but progressive reactor designs are required to achieve moderate solar radiation conversion efficiencies and H2 production rates. The process of fermentation utilizes free carbon as source of energy in agricultural by-products or wastes. However, the feasibility of fermentative hydrogen production depends upon the choice of the substrate.
  • ... In this scenario, the processes aimed at hydrogen production from biomass and waste are gaining growing attention [1,[4][5][6], with the thermochemical routes being those with best perspectives for their full scale implementation. Thus, hydrogen production from waste plastics has been mainly approached by means of steam gasification and pyrolysis-reforming processes [6]. ...
    ... Gasification allows for the conversion of waste plastics into a gaseous stream with varying contents of H 2 , CO, CO 2 , CH 4 and N 2 depending on process conditions and the gasifying agent used. The main advantage of gasification in relation to other thermochemical processes lies in its flexibility to valorize plastics of different composition or mixtures or plastics with other feedstocks. ...
  • ... Today's required hydrogen is generated totally from fossil resources including 48% from natural gas, 30% from heavy oils and naphtha, and 18% from coal. [65][66][67] Due to the significant importance of production costs and availability on fuel prices, fossil fuels hold on to be the influential source for world hydrogen generation. ...
    ... In comparison: the characteristics of biological methods can be enumerated as less energy intensive and environmentally friendly, due to the mild operation condition; however, they lead to low production rates of hydrogen. 66 Nonetheless, the production time is much lower in thermochemical processes. Furthermore, by considering the economic and environmental impacts, the output yield of produced hydrogen with gasification can be a thriving choice. ...
    Article
    The major logics resulting in hydrogen production can be mentioned as fossil fuel depletion and climate change. In this way, hydrogen is produced with the help of numerous processes based on traditional and alternative energy resources like coal, natural gas, wind, solar, biomass, and geothermal energy. Over the past decade, the attention of research institutions and industry has been drawn to hydrogen, inspired by developments in renewable energies. Hydrogen production can be considered as an exceptional choice to make complete utilization of the renewable energy. Among diverse technologies, hydrogen production based on geothermal energy offers great promise. In this paper, initially a concise summary of present and advancing hydrogen production technologies is presented, and secondarily a comprehensive review of research associated with hydrogen production based on geothermal energy is provided. Thirdly, the process descriptions of geothermal-assisted hydrogen production coupled with its technical, economic, and environmental aspects are addressed. Finally, comparative assessments of costs and environmental aspects related to hydrogen production based on different energy sources have been performed. In accordance with the results, the geothermal-assisted hydrogen production cost based on electrolysis is competitively lower than other sources like wind, solar thermal coupled with natural gas, solar PV, and grid. Also, the same behavior can be seen for geothermal-assisted hydrogen production cost based on thermochemical process.
  • ... While hydrogen plays a staple role in various industrial sectors, it also has a significant impact in the energy sector. Hydrogen has the highest energy density among all fuels: it has an energy yield of 122 kJ/g, which is approximately 2.75 times greater than other hydrocarbon fuels [2]. In addition to its high energy density, its rapid burning speed, high octane number, and zero-emission potential could make hydrogen a preferred fuel in energy sector [3]. ...
    ... Steam reforming of natural gas is the most common method for hydrogen production. The chemical reaction equations for steam reforming are as (2) At high temperatures of approximately 700-1000°C and with a nickel-based catalyst, methane reacts with steam to produce carbon monoxide and hydrogen (Eq. (1)). ...
    Article
    Steam gasification of polyethylene was conducted using a two-stage gasifier consisting of a fluidized bed gasifier and a tar-cracking reactor filled with active carbon. The main aim of the work was to produce H2-rich syngas and simultaneously reduce tar. The main reaction variable was the steam-to-fuel ratio. The possibility of gasification without using an electrostatic precipitator was also examined in the study. In addition, the effect of the type of distributor (hook-type and mesh-type distributor) located between the fluidized bed gasifier and tar-cracking reactor on coke formation was investigated. Finally, the possibility of in situ regeneration of active carbon with steam was explored. As a result, the syngas from the two-stage gasifier contained a maximum 66 vol% hydrogen and a minimum 0 mg/Nm3 tar. The syngas produced without using an electrostatic precipitator had similar quality to that obtained with an electrostatic precipitator, providing a positive indication for the implementation of the two-stage gasifier in commercial applications. Additionally, the mesh-type distributor was found to be excellent against coke formation. The in situ regeneration of active carbon with steam significantly recovered the textural properties of the original active carbon, yielding a surface area recovery rate of approximately 63%. A long-term gasification for 4 h with repetitive in situ regeneration of active carbon with steam produced a syngas having 55 vol% H2 on average and toluene as a tar component.
  • ... There are different techniques for the production of hydrogen, which include gasification, electrolysis, methane reforming, liquid reforming and biomass fermentation (Balat and Kırtay, 2010). The main disadvantage of electrolysis is its current high cost, while the main disadvantage of fossil derived hydrogen are the CO 2 emissions. ...
    ... This review focuses on the production of hydrogen from biomass and residual wastes and is limited to the production of hydrogen from gasification and pyrolysis followed by reforming, which are considered as the most mature and economical routes (Balat and Kırtay, 2010;Bridgwater, 1995). This article is structured as follows -first the main https://doi.org/10.1016/j.biortech.2019.122557 ...
    Article
    This article outlines the prospects and challenges of hydrogen production from biomass and residual wastes, such as municipal solid waste. Recent advances in gasification and pyrolysis followed by reforming are discussed. The review finds that the thermal efficiency of hydrogen from gasification is ~50%. The levelized cost of hydrogen (LCOH) from biomass varies from ~2.3–5.2 USD/kg at feedstock processing scales of 10 MWth to ~2.8–3.4 USD/kg at scales above 250 MWth. Preliminary estimates are that the LCOH from residual wastes could be in the range of ~1.4–4.8 USD/kg, depending upon the waste gate fee and project scale. The main barriers to development of waste to hydrogen projects include: waste pre-treatment, technology maturity, syngas conditioning, the market for clean hydrogen, policies to incentivize pioneer projects and technology competitiveness. The main opportunity is to produce low cost clean hydrogen, which is competitive with alternative production routes.
  • ... Hydrogen is a clean energy carrier with good potential for the use in proton exchange membrane fuel cell (PEMFC) [1,2]. The production of hydrogen from the renewable feedstock such as biomass has attracted great attention as biomass is carbon-neutral and widely distributed [3][4][5][6][7][8][9]. There are two major routes for the production of hydrogen from biomass, which are the gasification of biomass to directly produce the syngas [10,11] and the pyrolysis of biomass firstly to bio-oil and then the subsequent reforming of bio-oil to hydrogen [12][13][14][15]. ...
    Article
    This study investigated the steam reforming of a series of organic molecules with varied molecular structures (methanol, formic acid, ethanol, acetic acid, acetaldehyde, acetone, furfural, guaiacol), aiming to understand the impacts of functionalities of these organics on their reaction behaviors. The results showed that molecular structures drastically influenced reactivity and tendencies towards coking during steam reforming. Methanol and formic acid could effectively be reformed and coking was insignificant, as no cracking of CC bonds involved in their conversion. Ethanol, acetic acid, acetaldehyde or acetone was more difficult to be reformed, and coking was significant, especially for acetone or acetaldehyde bearing the carbonyl functionality that could be retained in the precursors of coke. The substantial amount of coke formed in steam reforming of furfural and guaiacol originating from their π-conjugated ring structures and the coke was more graphite-like. In comparison, the coke from reforming of ethanol, acetic acid, acetaldehyde or acetone were more disordered. The in situ DRIFTS studies of steam reforming indicated that the CC and CH functionalities were generated even at 100 °C, which could contribute to coking, when they could not be effectively gasified via steam reforming.
  • ... Up to date, the total annual worldwide hydrogen consumption is in the range of 400-500 billion Nm 3 [14]. The demand for hydrogen (H 2 ) is ever growing, with wide applications such as the refining of crude oil, production of ammonia and methanol, surface treatment in metallurgy process and other chemical uses. ...
    Thesis
    In order to develop a sustainable hydrogen economy, it is desirable to produce hydrogen from biogas (CH4 and CO2) or greenhouses gases (GHG). Dry reforming (DRM) and oxidative dry reforming of methane (ODRM) are promising routes to produce H2 and CO from GHG and have received much attention due environment concerns. Herein, these reactions were studied at low temperatures (600 -700 °C) over CeNiX(AlZ)OY, NiXMg2AlOY mixed oxides and Ni/SBA-15 supported catalysts. Various physico-chemical techniques were employed to characterize the catalysts, such as XRD, XPS, H2-TPR and Raman. The influences of different parameters were examined, such as reaction temperature, pretreatment in H2, Ni content, mass of catalyst and reactants concentration, in particular, at 600°C in harsh conditions (feed gases without dilution) on low mass of catalyst (10 mg). The best catalytic activity and selectivity are obtained on partially reduced catalysts at appropriate temperature. The addition of O2 increases CH4 conversion but decreases CO2 conversion, and O2/CH4 = 0.3 could be the optimized condition due to high activity, selectivity and low carbon formation. Finally, an active site involving Ni species in close interactions with other cations is proposed. It is related to a partially reduced catalyst involving anionic vacancies, O2- species, and cations, which is formed during the in situ H2 treatment or CH4 flow
  • ... The www.avidscience.com Top 5 Contributions in Energy Research and Development: 3rd Edition share of hydrogen produced from biomass in automotive fuel market will be high in next decade [108]. Biomass is harvested and processed to make triacylglycerides (TAGs) that can by trans-esterified to produce biodiesel with methanol, to yield methyl esters of fatty acids [109]. ...
    Chapter
    Full-text available
    The wide use of fossil fuels is gradually documented as unsus-tainable due to the significant reduction of supplies and emission of greenhouse gases (GHGs) into the atmosphere. Alternative and renewable energy sources are required to fulfill the ever increasing energy demands. Microalgae are the alternative renewable energy source as it has the potential to generate high amount of biomass which can be used for the production of third-generation biofuels. Moreover, utilization of biofuels also helps to preserve the atmosphere by many means like wastewater treatment, reduction in greenhouse gas emissions.
  • ... A lot of harmful gases and dust by burning fossil fuels also create many environmental pollution problems, such as greenhouse effect, acid rain, and haze (McGlade and Ekins 2015;Perera 2017). Fortunately, the photocatalytic technology based on semiconductor material makes use of abundant solar energy for driving the decomposition of water to produce hydrogen, bringing hope for energy source shortage and environment pollution (Balat and Kırtay 2010;Kaur et al. 2015). In this catalytic reaction, the most critical factor is a suitable photocatalyst with the characteristics of stable, efficient, and visible light response, such as ZnO, graphene, and MoS 2 (Zhou et al. 2014;Elangovan et al. 2015;Jiang et al. 2018). ...
    Article
    Full-text available
    Rational design and fabrication of phase junction is an important way and strategy to enhance the photocatalytic performance. In this paper, rutile/anatase phase junction is obtained in rutile nanoparticles decorated anatase thin film by laser ablation. The hydrogen generation of rutile/anatase composite film is 49.6 μL, which is remarkably higher than that of both anatase thin film and rutile decorated layer. The quantity of phase junctions between rutile and anatase is considered as a key factor of photocatalytic improvement by varying the amount of rutile nanoparticles. Moreover, the excellent photocatalytic stability of rutile/anatase composite film is also exhibited.
  • ... There are many hydrogen production methods currently used and found in literature. Unfortunately, hydrogen is mostly produced from fossil sources of which 48% from natural gas, 30% from heavy oils and 18% of coal [2,3]. ...
    Chapter
    In this chapter, a novel hydrogen generation and liquefaction process is presented. The source for this plant straw is chosen as biomass source. Biomass-based hydrogen generation and liquefaction plant consist of biomass gasifier, air separation unit, catalyst bed component with helium expander and liquid hydrogen storage tank sub-component. To examine the performance of plant, energy, and exergy analyses have performed. Also, the environmental analyses for various system design based on generation options have been conducted to reveal the CO2 emission of system. The energetic and exergetic efficiencies of plant for the base design parameters have been found as 68.26% and 64.72%, respectively. Parametric analysis results also indicate the effects of some variables on system performance and environmental effect of the system.
  • ... As a result, it is widely used in various industries, including (i) as an intermediate material for ammonia and methanol production, (ii) catalytic hydrocracking in the petroleum refining industry, (iii) grease hydrogenation for soap manufacturing, (iv) as an agent for silicon manufacturing, and (v) for unsaturated oil hydrogenation in the food industry [1,2]. In addition, H 2 is projected to become an essential energy carrier in fuel cell applications and for electricity generation in the automobile and energy sectors, respectively [3,4]. This is because H 2 has a high energy storage capacity (143 MJ/kg) [2], and only releases water vapor as waste unlike greenhouse gases and particles during fossil fuel combustion [5,6]. ...
    Article
    Industrially, the endothermic process of steam reforming is carried out at the lowest temperature, steam to carbon (S/C) ratio, and gas hourly space velocity (GHSV) for maximum hydrogen (H2) production. In this study, a three-level three factorial Box-Behnken Design (BBD) of Response Surface Methodology (RSM) was applied to investigate the optimization of H2 production from steam reforming of gasified biomass tar over Ni/dolomite/La2O3 (NiDLa) catalysts. Consequently, reduced quadratic regression models were developed to fit the experimental data adequately. The effects of the independent variables (temperature, S/C ratio, and GHSV) on the responses (carbon conversion to gas and H2 yield) were examined. The results indicated that reaction temperature was the most significant factor affecting both responses. Ultimately, the optimum conditions predicted by RSM were 775 °C, S/C molar ratio of 1.02, and GHSV of 14,648 h⁻¹, resulting in 99 mol% of carbon conversion to gas and 82 mol% of H2 yield.
  • ... In this case, one of the most promising second generation fuels is synthesis gas (SYNG) obtained by gasification of lignocellulosic material. Composition of produced SYNG is highly dependable on type of biomass and gasifier used [3,4], whereas it can be controlled by operational conditions [5][6][7] or altered by the use of catalysts [8][9][10]. However, for successful utilization in combustion engine SYNG should feature very low content of side products of gasification such as tars and particulate matter to allow for achieving low particle emissions from the ICE and to reduce possibility of deposition of tars in intake manifold of the engine. ...
    Article
    Full-text available
    The paper focuses on the implementation of a comprehensive and robust optimization procedure for a synthesis gas fired four-cylinder, spark ignited, 2.2 L industrial engine used in combined heat and power applications. Innovatively designed workflow is for the first time incorporating also a thorough operational stability analysis for evaluation of the engine operation durability while using off-design fuels. Design constraints of the engine operational space are set after in depth investigation of knock phenomena, cycle to cycle variations, emission formation phenomena and engine performance parameters. These are derived from experimental data, obtained from the engine, equipped with newly designed components. Throughout the paper, results obtained with synthesis gas are benchmarked to natural gas. With significant emphasis laid on analysis of lean operation conditions, as a measure to reduce environmental footprint of energy generation, a newly proposed optimum operation points reveal a possibility to obtain TA-Luft and EPA emission limits already with stoichiometric mixture. This allows to achieve a remarkably low power de-rating factor of only 16.5% and omission of any aftertreatment system. Therefore, findings of this study represent a significant improvement of current control strategies and enable further increase in specific power and thus economic attractiveness of distributed power generation techniques at enhanced durability while using low-carbon and renewable fuels.
  • ... In room temperature conditions generation of such productive fuel from very low energy contribution would be a huge environmental benefit [1]. So many decades, hydrogen production was achieved from a wide extent of resources, through various generation innovations, where most of it has been generated from non-renewable feedstock, for example, oil, coal, petroleum and gas [2]. Coal gasification and thermolytic burning is most utilized strategy for hydrogen production that contaminates the air due to the by production of ozone depleting substances (GHGs), thus contrarily impacts the supportability of hydrogen as a fuel asset. ...
    Article
    Full-text available
    This study was to evaluate the cause on the production of bio-hydrogen utilizing Distillery Spent Wash (DSW) and starch mixed wastewater in various mixing ratios under dark fermentation conditions with varying Hydraulic Retention Time in a batch reactor. The pH was kept constantly at 5.5 throughout the study. Thus the hydrogen production investigated in the batch reactor for following Hydraulic Retention Time 24h, 16h, 12h and 8h, the results revealed an extended and steady period of reactor operation with hydrogen percent in the biogas and hinders the methane production. The perfect mixing ratios and Hydraulic Retention Time were seen to be 50:50 (DSW: Starch wastewater) and 16h to 12h HRT with contrasting cumulative hydrogen yields of 3256.5ml and 2674.3ml with specific maximum production of hydrogen rate 468ml/L/d as well as 236.64ml/L/d with the best biomass improvement combination of 4.7g/l and 4.5g/l. The maximum Chemical Oxygen Demand removal rates of 68 and 50 percentage for the optimum HRT of 16h and 12h.
  • ... As a result, alternate methods for hydrogen production have drawn the attention of scientific research. Some alternate methods currently being investigated are; (i) fermentation, where biomass is converted into sugar-rich feedstocks that can be fermented to produce hydrogen (Balat and Kirtay, 2010;Nath and Das, 2003;Ni et al., 2006;Parthasarathy and Narayanan, 2014;Tanksale et al., 2010); (ii) splitting water, either by electrolysis, photochemical methods, photoelectrochemical methods, photo-biological methods (by using microbes, such as green algae, which consume water in the presence of sunlight, producing hydrogen as a byproduct,) or by using high temperature produced by nuclear reactors or solar concentrators (Chen et al., 2010;Han et al., 2007;Ismail and Bahnemann, 2014;Matsuoka et al., 2007;Nann et al., 2010). Once produced, hydrogen can be stored either as a compressed gas, a refrigerated liquefied gas, a cryo-compressed gas or in hydrides (Barthelemy et al., 2017). ...
    Thesis
    This study examined hydrogen production, CO2 storage and abiotic hydrocarbon generation duringgas-water-rock interactions by conducting hydrothermal experiments. The first part of this manuscriptpresents the simultaneous CO2 sequestration and hydrogen production by reacting New Caledonianmine tailings with CO2 saturated water at 473 K <T< 573 K and 15 MPa <PCO2< 30 MPa. The resultsshowed that the best conditions for both these reactions were 523 K <T<540 K at 30 MPa, capturing320.5 g of CO2 in the form of iron-rich magnesite ((Mg,Fe)CO3), and producing 0.57 g of H2 per 1 kgof mine tailings. In addition, considering the annual mine tailings production and the annual CO2emission in New Caledonia, the proposed method could potentially capture ~90 % of NewCaledonia’s CO2 emissions. In addition, the H2 produced by this method could offset ~10 % of New-Caledonia’s annual electrical consumption. Further investigation of secondary products and theirmineral-water interfaces at nanometer scale indicated that the reactions were taken place by dissolvingmine tailings followed by precipitation of iron rich magnesite, smectite group clay minerals(nontronite, vermiculite), traces of iron oxides and amorphous silica. Although, the phyllosilicates andamorphous silica could potentially act as passivating layers, slowing down the dissolution kinetics andconsequently limiting the CO2 storage and H2 production capacities, our experiments demonstratedthat the reactivity of New Caledonian mine tailings could also be lowered by the presence of glass.The second part of this manuscript presents the interaction of dissolved CO2 and H2 during thesynthesis of “abiotic” hydrocarbons, via Fischer-Tropsch type (FTT) synthesis in the presence of twopotential catalysts found in natural systems; sphalerite (ZnS) and marcasite (FeS2). The experimentswere conducted at 573 K and 30 MPa in gold capsules heated and pressurize in autoclaves. Hydrogennecessary for the reaction was provided by Fe2+ oxidation of minerals such as olivine(Mg1.80Fe0.2SiO4), fayalite (Fe2SiO4) and Fe-rich chlorite or chamosite (6Fe5Al(AlSi3)O10(OH)8).Methane (CH4) produced in our experiments was one order of magnitude higher than those reported inprevious studies when magnetite and iron oxide-chromite were used as catalysts for CH4 production,and in the same order of magnitude as pentlandite and Fe-Ni alloy catalysts. However, the smallconversion rates of inorganic carbon into organic carbon as well as the Schulz-Flory distribution ofC1-C4 alkanes demonstrated that sphalerite and marcasite do not explicitly catalyze the FTT synthesisof hydrocarbons under the conditions of these experiments.
  • ... Biotechnology for Biofuels *Correspondence: jufwang@scut.edu.cn 1 School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China Full list of author information is available at the end of the article the potential to replace traditional fuels because of its high energy capacity and environmental friendliness [7,8]. In 2018, the main sources for hydrogen were natural gas (approximate 48%), oil (30%) and coal (18%), while only 1.0% of hydrogen was derived from the conversion of biomass by microorganisms [9][10][11]. There are four hydrogen-producing methods using organisms, including the microbial electrolysis cell [12], biophotolysis [13], photofermentation [14], and dark fermentation [15][16][17]. ...
    Article
    Full-text available
    Background: As a renewable and clean energy carrier, the production of biohydrogen from low-value feedstock such as lignocellulose has increasingly garnered interest. The NADH-dependent reduced ferredoxin:NADP+ oxidoreductase (NfnAB) complex catalyzes electron transfer between reduced ferredoxin and NAD(P)+, which is critical for production of NAD(P)H-dependent products such as hydrogen and ethanol. In this study, the effects on end-product formation of deletion of nfnAB from Thermoanaerobacterium aotearoense SCUT27 were investigated. Results: Compared with the parental strain, the NADH/NAD+ ratio in the ∆nfnAB mutant was increased. The concentration of hydrogen and ethanol produced increased by (41.1 ± 2.37)% (p < 0.01) and (13.24 ± 1.12)% (p < 0.01), respectively, while the lactic acid concentration decreased by (11.88 ± 0.96)% (p < 0.01) when the ∆nfnAB mutant used glucose as sole carbon source. No obvious inhibition effect was observed for either SCUT27 or SCUT27/∆nfnAB when six types of lignocellulose hydrolysate pretreated with dilute acid were used for hydrogen production. Notably, the SCUT27/∆nfnAB mutant produced 190.63-209.31 mmol/L hydrogen, with a yield of 1.66-1.77 mol/mol and productivity of 12.71-13.95 mmol/L h from nonsterilized rice straw and corn cob hydrolysates pretreated with dilute acid. Conclusions: The T. aotearoense SCUT27/∆nfnAB mutant showed higher hydrogen yield and productivity compared with those of the parental strain. Hence, we demonstrate that deletion of nfnAB from T. aotearoense SCUT27 is an effective approach to improve hydrogen production by redirecting the electron flux, and SCUT27/∆nfnAB is a promising candidate strain for efficient biohydrogen production from lignocellulosic hydrolysates.
  • ... Hydrogen is the highest energy density among the fuel types and energy sources. The energy yield of H 2 (approximately 122 kJ/g) about 2.8 times higher than that of other fossil fuels [11] which means that energy production using H 2 is more efficient than using fossil fuels [12]. Since, the availability of H 2 is very scanty in nature (very less quantity) and also the value of production is incredible for potential H 2 challenging to be used as fuel. ...
    Article
    The present study is focused on bio hydrogen (H2) and bioplastic (i.e., poly-β-hydroxybutyrate; PHB) productions utilizing various wastes under dark fermentation, photo fermentation and subsequent dark-photo fermentation. Potential bio H2 and PHB producing microbes were enriched and isolated. The effects of substrate (rice husk hydrolysate, rice straw hydrolysate, dairy industry wastewater, and rice mill wastewater) concentration (10-100%) and pH (5.5-8.0) were examined in the batch mode under the dark and photo fermentation conditions. Using 100% rice straw hydrolysate at pH 7, the maximum bio H2 (1.53 ± 0.04 mol H2/mol glucose) and PHB (9.8 ± 0.14 g/L) were produced under dark fermentation condition by Bacillus cereus. In the subsequent dark-photo fermentation, the highest amounts of bio H2 and PHB were recorded utilizing 100% rice straw hydrolysate (1.82 ± 0.01 mol H2/mol glucose and 19.15 ± 0.25 g/L PHB) at a pH of 7.0 using Bacillus cereus (KR809374) and Rhodopseudomonas rutila. The subsequent dark-photo fermentative bio H2 and PHB productions obtained using renewable biomass (i.e., rice husk hydrolysate and rice straw hydrolysate) can be considered with respect to the sustainable management of global energy sources and environmental issues.
  • ... Biohydrogen technologies are still yet to be fully developed [8,9], they can be sustainable routes for biomass conversion to hydrogen. Technologies for conversion of biomass to hydrogen-rich gas can by classified generally into thermochemical and biochemical processes [10][11][12]. ...
  • ... Production of biohydrogen from biomass along with some covaluable products makes the process cost-effective when compared with the production of biohydrogen from steam reforming of natural gas. Less CO 2 emission, its environmental sustainability and ecofriendly behavior make this gaseous fuel viable, but simultaneously, there are certain challenges in its production from biomass, such as seasonal availability of feedstocks, and complex production process, which limits its production [117]. Production of biohydrogen from starch-containing residue obtained from the agricultural sector has been reported [118]. ...
  • ... The global annual electricity production from biomass has risen from 227 TWh in 2004 to 646 TWh in 2016 ( REN21 Secretariat, 2015. Biomass includes either waste streams, such as Municipal Solid Wastes (MSW), animal wastes and food processing wastes or aquatic plants including algae (Balat and Kırtay, 2010). Methods of biomass thermochemical and biological conversions into heat were developed for the past years as alternatives to fossil resources (Archer and Steinberger-wilckens, 2018). ...
    Article
    Full-text available
    Electric vehicles expansion is accelerating rapidly due to e-mobility’s massive contribution in reducing fossil fuel consumption and CO2 emissions. Fulfilling the charging requirements of millions of electrical vehicles from the grid would overload the network and introduce substantial burden on the power sector. This study proposes, and thermodynamically assesses, a grid-independent and renewable energy-based, stand-alone electrical vehicle charging station consisting of CPV/T, wind turbine and biomass combustion-based steam Rankine cycle plant. Hydrogen and ammonia-based fuel cells are integrated in the design along with electrochemical, chemical and thermal storage units to ensure uninterrupted charging services during night times and unfavorable weather conditions. Since the proposed design is suggested for use in the State of Qatar, which is located in a hot region, an absorption cooling system is incorporated to cool the produced NH3 gas and convert it into liquid phase for optimal storage purposes and to maintain the operating temperature of the battery system within the allowable limits. The thermodynamic analysis followed in this study is based on writing the balance equations for mass, energy, entropy and exergy for the system’s components along with their energy and exergy efficiency equations. The results show that the energy generated from renewable energy sources and fuel cells are sufficient to fast-charge 80 electrical vehicles daily. The energy efficiencies of H2 fuel cell, NH3 fuel cell, CPV/T, wind turbine and energetic COP of the absorption cooling system are found to be 77%, 72%, 45%, 43% and 0.72, respectively. The exergy efficiency of CPV/T and the exergetic COP of the absorption cooling system are found to be 37% and 0.19, respectively. The overall energy and exergy efficiencies of the proposed integrated system are found to be 45% and 19%, respectively
  • ... Among the several possibilities, biomass is seen as a strategic feedstock for the production of renewable energy and materials. One of the possible products of biomass exploitation is hydrogen, through thermochemical or biological routes (Balat and Kirtay, 2010). ...
    Article
    Full-text available
    Butanol is a by-product obtained from biomass that can be valorized through aqueous phase reforming. Rh/ZrO2 catalysts were prepared and characterized, varying the size of the support particles. The results showed a relatively mild effect of internal mass transport on butanol conversion. However, the influence of internal transport limitations on the product distribution was much stronger, promoting consecutive reactions, i.e., dehydrogenation, hydrogenolysis, and reforming of propane and ethane. Hydrogen consuming reactions, i.e., hydrogenolysis, were more strongly enhanced than hydrogen producing reactions due to internal concentration gradients. Large support particles deactivated faster, attributed to high concentrations of butyraldehyde inside the catalyst particles, enhancing deposit formation via aldol condensation reactions. Consequently, also the local butyric acid concentration was high, decreasing the local pH, enhancing Rh leaching. The influence of internal transfer limitation on product distribution and stability is discussed based on a reaction scheme with three main stages, i.e., (1) formation of liquid intermediates via dehydrogenation, (2) formation of gas via decarbonylation/decarboxylation reactions, and (3) hydrocarbon hydrogenolysis/reforming/dehydrogenation.
  • ... Hydrogen has advantageous properties as a fuel for combustion engines. It is also used as a clean energy source for fuel cells, clean energy carrier for heat supply, and transportation purposes [18,[33][34][35][36]. Hydrogen exhibits the highest energy density amongst all fuels including all hydrocarbons which is about 122 kJ kg -1 [37]. The combustion of hydrogen produces no harmful emissions but only water [36,38]. ...
    Article
    A systematic review of the hydrogen production from biomass steam gasification is presented in this study. The equilibrium modelling and simulation studies using various techniques for effective hydrogen production has been presented. Heat integration, economic analysis of the hydrogen production, and systematic design algorithms research publications are reviewed and presented for energy efficient and economic hydrogen production from various biomass feedstock. The comparison and analysis of results strongly suggest the viable potential of biomass steam gasification for hydrogen production from small to large scales having applications for thermal heat, power generation, and many other industrial applications.
  • ... It has maximum energy content per unit mass, and water is the only by-product generated during its combustion [7]. It has a high yield of energy (~122 kJ g -1 ), which is 2.75 times higher than that of hydrocarbon fuels [8]. This energy is recognized as one of the most promising fuels for fulfilling future energy demands for various applications, i.e., electricity, household, fuel for automobiles, jet planes, hydrogen-based power industries, and domestic purposes [9]. ...
    Article
    The aim of this study is to enhance the production of hydrogen (H2) produced through the co‐gasification of empty fruit bunch of palm oil by adding charcoal. For that purpose, physiochemical characterization of raw feedstocks was performed to find out its exergy potentiality. Raw feedstock and gasified charcoal were examined using XRD, FESEM with EDX and TEM analyses. The end product of produced gas was analyzed using gas chromatography‐thermal conductivity detector. Gasification experiments were performed using a pilot scale downdraft gasifier. Charcoal was loaded into the reactor chamber with empty fruit bunch. Then different mixtures of EFB with charcoal (0‐40%) were co‐gasified for hydrogen production. The heating value, composition of product gas, yield of hydrogen and exergy efficiency were used to verify the enhancement of hydrogen production during co‐gasification process. The results revealed that hydrogen yield increases as charcoal to empty fruit bunch ratios are increased. In particular, the charcoal with empty fruit bunches of palm oil gives much higher yield of H2 than lower charcoal ratios or solely empty fruit bunches. Therefore, enhanced hydrogen fuel can be used for future energy demand.
  • ... For all the above and as a consequence of unstable oil prices and the alarming climate change, biomass gasification has increasingly received interest [4]. Indeed, this is a versatile and interesting way to re-use different wastes (e.g., agricultural and urban wastes, energy crops, food and industrial processing residues) to produce bio-syngas, which can be used for electrical power generation (fuel cells, gas turbine or engine), or as feedstock for the synthesis of liquid fuels and chemicals such as methanol [5]. ...
    Article
    Full-text available
    Identifying the suitable reaction conditions is key to achieve high performance and economic efficiency in any catalytic process. In this study, the catalytic performance of a Ni/Al2O3 catalyst, a benchmark system—was investigated in steam reforming of toluene as a biomass gasification tar model compound to explore the effect of reforming temperature, steam to carbon (S/C) ratio and residence time on toluene conversion and gas products. An S/C molar ratio range from one to three and temperature range from 700 to 900 °C was selected according to thermodynamic equilibrium calculations, and gas hourly space velocity (GHSV) was varied from 30,600 to 122,400 h−1 based on previous work. The results suggest that 800 °C, GHSV 61,200 h−1 and S/C ratio 3 provide favourable operating conditions for steam reforming of toluene in order to get high toluene conversion and hydrogen productivity, achieving a toluene to gas conversion of 94% and H2 production of 13 mol/mol toluene.
  • ... Production of hydrogen from biomass is feasible and very promising for future energy development [77,78]. Conventional processes for H2 derived from biomass require critical reaction conditions [79][80][81][82][83][84]. Photocatalysis applied for reforming of biomass not only overcomes the problem of critical conditions required by thermal catalysis, but also combines the solar energy with biofuels [85]. ...
    Article
    Full-text available
    Hydrogen is considered to be an ideal energy carrier to achieve low-carbon economy and sustainable energy supply. Production of hydrogen by catalytic reforming of organic compounds is one of the most important commercial processes. With the rapid development of photocatalysis in recent years, the applications of photocatalysis have been extended to the area of reforming hydrogen evolution. This research area has attracted extensive attention and exhibited potential for wide application in practice. Photocatalytic reforming for hydrogen evolution is a sustainable process to convert the solar energy stored in hydrogen into chemical energy. This review comprehensively summarized the reported works in relevant areas, categorized by the reforming precursor (organic compound) such as methanol, ethanol and biomass. Mechanisms and characteristics for each category were deeply discussed. In addition, recommendations for future work were suggested.
  • ... Production of biohydrogen from biomass along with some covaluable products makes the process cost-effective when compared with the production of biohydrogen from steam reforming of natural gas. Less CO 2 emission, its environmental sustainability and ecofriendly behavior make this gaseous fuel viable, but simultaneously, there are certain challenges in its production from biomass, such as seasonal availability of feedstocks, and complex production process, which limits its production [117]. Production of biohydrogen from starch-containing residue obtained from the agricultural sector has been reported [118]. ...
    Chapter
    The industrial revolution and continuous greenhouse gases (GHGs) emission may lead to environmental changes to severe and irretrievable state. To mitigate this change not only reduction in GHGs emission but also atmospheric carbon dioxide capture and storage (CCS) will also be required. Bioenergy with CCS (BECCS) has been modeled to bring down the CO2 concentration in the atmosphere to below current range by delivering negative emissions. We begin this chapter with the introduction of negative emission concept then biomass feedstock that has been previously taken up CO2 to produced energy. The next section describes different methods to sequester CO2 in detail. Furthermore, the chapter discussed first-, second- and third-generation biofuel based on the different feedstock used. Various processes of biomass conversion into liquid biofuel and other valuable bioproducts by applying a biorefinery approach have been mentioned.
  • ... Generally, threre are two steps involved in neutral pH HER, including H 2 O adsorption/activation and H recombination on the surface of the catalyst; [62] so, a strong bonding of H 2 O and neither too strong nor too weak bonding of H to the surface are desired. [63,64] As displayed in Fig. 5c, Ru in NiRu 0.13 -BDC shows much lower adsorption energy of H 2 O (ΔG H2O* ) compared with Ni in Ni-BDC and NiRu 0.13 -BDC, indicating the strongest water adsorption, which bene ts for the following step to generate adsorbed H atoms. [65,66] In addition, ΔG H* is often used as one of the key descriptors to predict and evaluate the activity for HER on catalyst surface and the promising catalysts should possess thermoneutral ΔG H* . [67] Interestingly, the ΔG H* of Ni in NiRu 0.13 -BDC (Fig. 5d) is very close to the optimal value of ΔG H* = 0 eV. ...
    Preprint
    Full-text available
    Developing high-performance electrocatalysts toward hydrogen evolution reaction is important for clean and sustainable hydrogen energy, yet still challenging. Herein, we report a single-atom strategy to construct excellent metal-organic frameworks (MOFs) hydrogen evolution reaction (HER) electrocatalyst (NiRu0.13-BDC, BDC: terephthalic acid) by introducing atomically dispersed Ru. Significantly, the obtained NiRu0.13-BDC exhibits outstanding HER activity in all pH, especially with a low overpotential of only 36 mV at a current density of 10 mA cm-2 in 1 M phosphate buffered saline (PBS) solution, which is comparable to commercial Pt/C. X-ray absorption fine structures and the density functional theory calculations reveal that introducing Ru single-atom can modulate electronic structure of metal center in the MOF, leading to the optimization of binding strength for H2O and H*, and the enhancement of HER performance. This work establishes single-atom strategy as an efficient approach to modulate electronic structure of MOFs for catalyst design.
  • ... In this context, renewable biomass obtained from various bioresources is considered an ideal feedstock, and it is attracting a great deal of attention globally. Currently, the production of hydrogen from such renewable biomass accounts for only 1%, indicating the huge potential that such resource has for further utilization [162]. ...
    Chapter
    Bioresources are the naturally occurring materials which are sustainably renewable and biodegradable. A variety of bioresources are present on the planet earth, which mainly includes agricultural crops, waste from agriculture, forest and various industries, marine resources like fishes and aquatic crustaceans, weeds, grasses, etc. All these bioresources are of huge significance and can be used as raw material or feedstocks for the production of a wide range of valuable products that are economically and industrially important. The bioresources are considered as one of the centers of bioeconomy. On the one hand, these are responsible for the generation of employment and sufficient income to individuals and industries that collectively contribute to the economy of the nation. However, on the other hand, overexploitation of bioresources can generate adverse impacts on the environment and can destroy the environment. Similarly, improper utilization of these bioresources can have adverse social and economic effects. The main aim of the present chapter is to discuss the type, composition, and properties of various bioresources and their applications in the production of a wide range of high-value products. Moreover, different environmental, social, and economic impacts due to the utilization of bioresources are also discussed.
  • ... Fossil fuel based processes are nowadays mostly used for producing hydrogen, whose demand is growing annually, with ammonia production and oil refining being the principal applications [12]. Besides, hydrogen is a clean fuel with greater energy density than other fuels [13] and surely will play an essential role as energy carrier in the future. ...
    Article
    A Ni/Al2O3 catalyst has been modified incorporating CeO2 and MgO promoters in order to improve its performance in the steam reforming of biomass pyrolysis volatiles. Ni/Al2O3, Ni/CeO2-Al2O3 and Ni/MgO-Al2O3 catalysts have been prepared and fresh and deactivated catalysts have been characterized by N2 adsorption/desorption, X-ray Fluorescence (XRF), Temperature Programmed Reduction (TPR), X-ray powder diffraction (XRD), Temperature Programmed Oxidation (TPO), Transmission Electron Microscopy (TEM) and a technique based on Fourier Transform Infrared Spectroscopy-Temperature Programmed Oxidation (FTIR-TPO). The results obtained revealed a similar initial activity for the three catalysts tested (conversion higher than 98%), whereas stability has been greatly improved by incorporating CeO2 as promoter, as it enhances the gasification of coke precursors. However, Ni/MgO-Al2O3 catalyst is slightly less stable than Ni/Al2O3, presumably as a result of its lower reducibility due to the formation of MgAl2O4 spinel phase. Catalysts deactivation has been associated with coke deposition, although sintering phenomenon became also evident when the Ni/CeO2-Al2O3 catalyst was tested. The coke deposited on the catalysts does not present any specific morphology, which is evidence of its amorphous structure in the three catalysts studied.
  • Article
    In this study, steam gasifications of a kind of marine biomass, i.e., Zostera marina (eelgrass), and the biochars derived from pyrolysis of it were carried out for the biohydrogen production in a fixed-bed reactor. The effects of reaction temperature and water injection rate on the hydrogen production were investigated. In order to understand the effect of sea salts attached on the surface of eelgrass for the hydrogen production, the eelgrass washed by water (washed-eelgrass) was also used as the feedstock. It was observed that hydrogen productions from the gasification of washed-eelgrass as well as its biochar were higher than those of raw eelgrass and its biochar, indicating that the impurities of raw eelgrass had a negative effect on the hydrogen production. The biochar derived from the pyrolysis of washed eelgrass at 550 °C had the largest amount of hydrogen yield at the gasification temperature of 850 °C with a water injection rate of 0.15 g/min. It was found that both the hydrogen production and reaction rates were enhanced by mixing washed-eelgrass biochar obtained at 350 °C with the calcined seashells at a weight ratio of 1 to 2, especially at the gasification temperature of 650 °C. Meanwhile, in the presence of the calcined seashell, CO2 content decreased sharply whereas the hydrogen yield had no obvious increase.
  • Book
    Full-text available
    Preface to ”Membrane and Membrane Reactors Operations in Chemical Engineering” In the last four decades, membrane technology has largely contributed to the valorization of process intensification strategy in several strategic engineering sectors, demonstrating the high potentialities of membrane operations as an alternative approach to conventional processes. In the field of chemical engineering, high process efficiency and easy operation, high product selectivity and permeability, elevated compatibility in integrated membrane systems, energy saving and environmentally friendly processes, and membrane and membrane reactor operations represent a well-established scientific and industrial reality, as also reported in the various works collected in this Special Issue. In this Special Issue, Rahimpour and co-authors (Water and Wastewater Treatment Systems by Novel Integrated Membrane Distillation (MD)) have reviewed the recent state-of-the-art and sophisticated advances in membrane distillation technology for wastewater treatment. Di Profio and co-authors (Ionic Liquid Hydrogel Composite Membranes (IL-HCMs)) presented a novel experimental route for the preparation of hydrogel composite membranes for utilization as membrane contactors in desalination applications. Dittmeyer and co-authors (Experimental Investigation of the Gas/Liquid Phase Separation Using a Membrane-Based Micro Contactor) investigated the gas/liquid phase separation of CO2 from a water–methanol solution at the anode side of a micro direct methanol fuel cell using hydrophobic polytetrafluoroethylene as a membrane microcontactor. Cassano and co-authors (A Multivariate Statistical Analyses of Membrane Performance in the Clarification of Citrus Press Liquor) performed statistical analysis on the experimental behaviors of polyvinylidene fluoride membranes applied in the clarification of citrus press liquor. Marino et al. (Hydrogen and Oxygen Evolution in a Membrane Photoreactor Using Suspended Nanosized Au/TiO2 and Au/CeO2) proposed a method for one-step hydrogen and oxygen separation through a photocatalytic membrane reactor using a modified Nafion membrane. Through experiments, Morico et al. (Solar Energy-Assisted Membrane Reactor for Hydrogen Production) studied a pilot-scale membrane reformer coupled with solar-assisted molten salt-heating to generate hydrogen, also proposing an economic analysis of its industrial feasibility at reduced environmental impact. Caravella et al. (Dry Reforming of Methane in a Pd–Ag Membrane Reactor: Thermodynamic and Experimental Analysis) performed an experimental campaign on the CO2 reforming of methane in a catalytic Pd-based membrane reactor, including a detailed thermodynamic analysis, demonstrating the benefits of this membrane-integrated reaction process while making the production of syngas more efficient and with additional environmental advantages. To conclude, Holgado and Alique (Preliminary Equipment Design for On-Board Hydrogen Production by Steam Reforming in Palladium Membrane Reactors) presented the design of an on-board hydrogen production Pd-based membrane reactor integrated to a PEM fuel cell, demonstrating the feasibility of a one-step process for vehicle applications. Last but not least, the Editor of this Special Issue would like to thank all the authors for their excellent work and acknowledge their contribution to the success of this project. Adolfo Iulianelli Special Issue Editor
  • Poster
    The greatest concern for the world today is the environmental pollutions that is mainly taking place due to the rapid utilization of natural resources and industrialization. The most common root for this is the release of harmful gases by the combustion of fossil fuels, which causes various environmental issues. There is need to overcome these issues by developing advance and alternate energy sources, which can mimic this issues without any impact in the surroundings. Although the conventional fuels are depleting at a higher rate today like reserves of oil, coal and natural gas, therefore research is carried out for the sustainable environment for future generations. However, hydrogen assures to be a potential clean, renewable and environmental friendly energy source because of its easy conversion accessibility to electricity by fuel cells and it does not involve any emission of greenhouse gases like CO2, which are released from the combustion as a clean fuel. Biological hydrogen production generally can be carried out by two mechanisms-the fermentation and photo biological production. Photo biological hydrogen production has the advantage that utilizes solar radiation to run the operation but progressive reactor designs are required to achieve moderate solar radiation conversion efficiencies and H2 production rates. The process of fermentation utilizes free carbon as source of energy in agricultural by-products or wastes. However, the feasibility of fermentative hydrogen production depends upon the choice of the substrate. WHY BIOHYDROGEN: The sources of feedstocks for the production of bio hydrogen varies from process to process and the technology employed. The table below shows the comparison of the biological feedstocks used in the production of hydrogen and the technology employed to carry out the process. SOURCES OF BIOHYDROGEN PRODUCTION: The sources of feedstocks for the production of bio hydrogen varies from process to process and the technology employed. The table below shows the comparison of the biological feedstocks used in the production of hydrogen and the technology employed to carry out the process. ENZYMES: The production of biohydrogen as a future energy resource using potential microorganisms is due to a novel enzymes which can catalyze the reaction of hydrogen production. The family of enzymes that catalyze the reversible oxidation of hydrogen into its elementary particle constituents, two protons (HC) and two electrons is named as a Hydrogenase (Das et al., 2006): 2H+ 2e-→H2 Mainly two enzymes are involved in the production of hydrogen : hydrogenase [types of hydrogenases: (i) hup-encoded [NiFe]-uptake hydrogenases, (ii) hox-encoded [NiFe]-bidirectional hydrogenases (iii) [FeFe]-hydrogenases, (iv) [NiFeSe]-hydrogenases (as one of the Ni-bound cysteine residues of [NiFe]-hydrogenases is replaced by selenocysteine), and (iv) [Fe]-only hydrogenases]. and nitrogenase. Fe-hydrogenase enzyme is used in the biophotolysis processes, photo-fermentation processes utilize nitrogenase (Manish and Banerjee, 2007). Hydrogenase enzymes present in microalgae, cyanobacteria, and anoxygenic photosynthesis and fermentative bacteria while nitrogenase present in cyanobacterial heterocysts and purple non-sulphur bacteria (Meyer et al., 1978). Nitrogenases is complex enzyme made up of two subunits : (i) the reductase subunit and (ii) the dinitrogenase complex. PRODUCTION PROCESSES: Biological hydrogen production achieved by anaerobic and photosynthetic microorganisms using carbohydrate-rich and non-toxic raw materials, industrial waste,agricultural waste helps in development of eco-friendly and cleaner form of energy. Biohydrogen can be produced in both anerobic (a by-product during conversion of organic wastes into organic acids, which are then used for methane generation. The acidogenic phase of anaerobic digestion of wastes can be manipulated to improve hydrogen production) and Photosynthetic processes Photosynthetic processes include algae, which uses CO2 and H2O for hydrogen gas production and Some photo-heterotrophic bacteria utilize organic acids such as acetic, lactic, and butyric acids to produce H2 and CO2 (Kapdan and Kargi, 2006) there is difference in the yield. A successful biological conversion of biomass to hydrogen depends strongly on the processing of raw materials to produce feedstock, which can be fermented by the microorganisms (Li and Chen, 2007). Biological hydrogen production generally can be carried out by two mechanisms 1.Photo biological production (Bio photolysis) 1.1Indirect Bio photolysis This process consists of two stages i.e. photosynthesis for carbohydrate accumulation and dark fermentation of the carbon reserve for hydrogen production (Yu and Takahashi, 2007). In the initial stage the acidogenic bacteria present in the environment produce some hydrogen by degrading waste carbohydrate matter into simple organic acids and alcohols while in the next stage In the second stage these organic acids used as a substrate to photoheterotrophic bacteria for additional hydrogen production (Lee et al., 2007). 12H2O+6CO2+ Light energy → C6H12O6 + 6O2 C6H12O6 + 12H2O + Light energy → 12H2 + 6CO2 The mutant strains of A. Variabilis is developed which has potential of hydrogen production with the rate of the order of 0.355 mmol/h per liter (Manish and Banerjee, 2007) by indirect bio photolysis. The hydrogen production by Cyanobacteria has been studied for over three decades and the chemistry of production showed below.
  • Chapter
    Wasserstoff ist ein notwendiger Rohstoff in der Erzeugung von Ammoniak, für Hydrocracking sowie für die Herstellung von Methanol und Pharmazeutika und wird auch von Lebensmittel- und Metallindustrien benötigt. Nach dem Stand der Technik ist die Herstellung von Wasserstoff von der Verwendung fossiler Ausgangsstoffe und Energieträger abhängig und damit mit einer erheblichen CO2-Emission verbunden. Kapitel 3 beschreibt die derzeit eingesetzten Verfahren und benennt nachhaltigere Alternativen .
  • Article
    Electrolysis in neutral pH solutions (e.g., wastewater and seawater) presents a transformative way for environmentally friendly, cost-effective hydrogen production. However, one of the biggest challenges is the lack of active, robust hydro-gen evolution reaction (HER) catalysts. Herein we present a novel catalyst with dual active sites of MoP2 and MoP which function synergistically to promote HER in neutral pH solutions. In our microbial electrolysis cell (MEC) test which uses neutral pH wastewater as feedstock, the new catalyst delivers an average HER current density of 157 A m-2Cathode-Surface-Area, higher than Pt catalyst (145 A m-2Cathode-Surface-Area) – with the same amount of catalyst loading, ~5 times higher than the state-of-art Pt group metal (PGM)-free catalysts in MECs. The new catalyst also outperforms Pt in natural seawater with ~10% higher and more stable HER current density. The fundamental reason for the enhanced HER performance is identified to be the synergy between MoP2 and MoP phases, with MoP2 promoting H2O dissocia-tion and MoP efficiently converting Had to H2.
  • Article
    Nigeria is blessed with abundant biomass throughout her six geo-political zones. However, biomass energy is largely used in the rural areas mainly for off grid purposes. The method of such biomass conversion is based on traditional combustion process which is grossly inefficient with attendance environmental implications. This paper addresses the use of gasification technology for the conversion of biomass to high value fuel. It presents biomass gasification as a solution to the menace of inadequate power generation, dependence on fossil fuel, greenhouse gas (GHG) emission and inappropriate disposal of wastes. The paper also highlights the need for focus to be shifted to other means of renewable energy in the country rather than hydropower and bioethanol on which the energy policy in the country is concentrated on.
  • Chapter
    Hydrogen attracts much attention as both a fuel and an energy carrier due to its high energy density and overall cleanliness. It can also be stored and has very low environmental impacts at the point of use. However, hydrogen faces several major challenges, including high production cost, inefficient storage and transportation, and low social acceptance. On the other hand, a concern related to the utilization of low-rank fuels as energy sources increases significantly due to economic and environmental issues. This chapter discusses the possible hydrogen production from low-rank fuels (such as low-rank coal and industrial waste biomasses) and its storage technologies. If managed efficiently, hydrogen has the potential to replace conventional utilization of currently adopted carbon-based fuels. This chapter discusses advanced production and storage systems for hydrogen from several low-rank fuels, especially in terms of total energy efficiency. The main objectives cover the development and proposals of integrated hydrogen and storage systems optimized for each fuel, and clarification of several key operating parameters to increase energy efficiency of the developed systems. The analyzed low-rank fuels cover low-rank coal and industrial wastes, including empty fruit bunch and black liquor. In addition, several potential hydrogen storage methods, such as liquid hydrogen, liquid organic hydrogen carrier, and ammonia, are also discussed to clarify their techno-economic performance. Finally, as potential future secondary energy sources, electricity and hydrogen are requested to be mutually convertible. The power-to-gas system is also discussed at the end of the chapter.
  • Article
    This review considers the problems associated with the development and operation of highly active and stable structured catalysts for biogas/biofuel conversion into syngas and hydrogen based on nanocrystalline oxides with fluorite, perovskite, and spinel structures and their nanocomposites promoted by nanoparticles of platinum group metals and alloys based on nickel. The design of these catalysts is based on finding the relationships between the methods of their synthesis, composition, real structure/microstructure, surface properties, and oxygen mobility and reactivity largely determined by the metal–support interaction. This requires the use of modern structural, spectroscopic, kinetic methods, and mathematical modeling. Thin layers of optimized catalysts deposited on structured heat-conducting supports demonstrated high activity and resistance to carbonization in the processes of biogas and biofuels conversion into syngas, and catalysts deposited on asymmetric ceramic membranes with mixed ionic–electronic conductivity allowed oxygen or hydrogen to be separated from complex mixtures with 100% selectivity.
  • Preprint
    This article broadly reviews the state-of-the-art technologies for hydrogen production routes, and methods of renewable integration. It outlines the main techno-economic enabler factors for Australia to transform and lead the regional energy market. Two main categories for competitive and commercial-scale hydrogen production routes in Australia are identified: 1) electrolysis powered by renewable, and 2) fossil fuel cracking via steam methane reforming (SMR) or coal gasification which must be coupled with carbon capture and sequestration (CCS). It is reported that Australia is able to competitively lower the levelized cost of hydrogen (LCOH) to a record $(1.88-2.30)/kgH2 for SMR technologies, and $(2.02-2.47)/kgH2 for black-coal gasification technologies. Comparatively, the LCOH via electrolysis technologies is in the range of $(4.78-5.84)/kgH2 for the alkaline electrolysis (AE) and $(6.08-7.43)/kgH2 for the proton exchange membrane (PEM) counterparts. Nevertheless, hydrogen production must be linked to the right infrastructure in transport-storage-conversion to demonstrate appealing business models.
  • Article
    Escalating global energy demand has opened up a wide avenue for alternative energy research. One such alternative energy is biohydrogen (H2) which is now projected as clean energy, since harnessed by biological means with high energy content; it finds the application on a broader scale. Recently, the employment of sustainable energy origins for generating biohydrogen has gained traction worldwide. Biohydrogen sourced from organic resources mainly of waste origins promises to provide sustainable energy in comparison with its other counterparts. The current work spotlights the various waste materials sourced for the generation of biohydrogen, bio-processing approaches, various microbes involved, conditions, factors, various relative advantages, and challenges. Diversities in biohydrogen processes such as utilizing different waste materials and biomass as raw material, probed akin to their chattels in the environment, bioreactor operative factors (temperature, pH, and partial pressure) are summarized. In this article, we have pursued to explicate the major hurdles confronted while procuring biohydrogen as a profit-making proposition by creating an appraisal of its improved role, also taking into account the diverse mechanism and procedures, while assessing its future perspectives.
  • Chapter
    Fossil fuels have been the cornerstone of our energy infrastructure for a number of centuries now. In recent decades, there has been an emergence of bioenergy and hydrogen as a modern energy source to supply our civilization. Despite this, fossil fuels are still the main energy source for our society, slowing the adaptation of hydrogen and biomass technologies. In this chapter, the history and current utilization of hydrogen and biomass energy are discussed to identify the adaptation of these energy sources.
  • Chapter
    Full-text available
    Biogas has become one of the most attractive pathways among the renewable energy sources essential to address major modern challenges such as climate change and energy depletion in recent years. Biogas derives from the degradation of organic materials through anaerobic digestion by microorganisms. Such organic materials generally come from waste feedstocks. Therefore, besides being a sustainable replacement for fossil fuels, biogas helps control waste. Agricultural and industrial residues, municipal organic waste and sewage sludge are thus common feedstock sources, including seeds, grains and sugars, lignocellulosic biomass such as crop residues and woody crops, or high carbohydrate algae. Because of its versatility in usage and storage space, biogas plays an significant role in managing potential electricity grids. Through biogas production and utilisation, our society can go deeper into green energy applications. This Chapter will give an introduction the the current energy sector and where biogas can be used as a substitute for decarbonisation of the energy sector.
  • Chapter
    Hydrogen production from residual biomass and wastes is a sustainable approach for reducing their final accumulation in landfills and simultaneously a very promising alternative for the energy recovery. Most developed technologies to produce H2 from residual biomass and wastes are reviewed in this chapter focusing on the separation/purification of the produced hydrogen. Suitability of both thermochemical and biological technologies for hydrogen production is described, and examples of industrial processes are included. Basics of hydrogen separation/purification with membranes are detailed, and suitable separation technologies for the purification of hydrogen produced from biomass and waste conversion are presented focusing on the most recent advances in Pd-based membranes. The use of membrane reactors in which the traditional chemical reaction is combined to the continuous extraction of the main product with high purity, in this case hydrogen, is particularly interesting, being also addressed the most recent developments in this field.
  • Article
    Waste organic biomass is regarded as the most suitable renewable source for conversion to produce biofuels and biochemicals. Owing to its high‐energy potential and abundancy, lignocellulosic biomass can be utilized to produce alternative energy in the form of gaseous and liquid biofuels. Microbial conversion of waste biomass is found to be the most successful technology for the generation of biohydrogen through dark fermentation. Hydrogen is considered as the promising renewable green energy source for a sustainable future. Different biological hydrogen production technologies along with process parameters are described in this review paper although the emphasis is on dark fermentation. The production of biohydrogen from various substrates are summarized in this article along with the integrated mode of dark fermentation and photo‐fermentation. Hydrogen generation through biological water‐gas shift reaction is also highlighted.
  • Chapter
    Interest in hydrogen energy has gained momentum in recent years as a sustainable and renewable alternative to the fast‐depleting fossil fuels. It also provides an additional benefit of not emitting any greenhouse gases (GHG) which provides an incentive to adopt this clean fuel to all countries struggling to meet the GHG limitations as per the Paris agreement to combat climate change. Agricultural residues or second‐generation feedstocks or lignocellulosic biomass are possible alternate feedstocks for energy production as they are abundant, cheap resources whose use adds little or no net greenhouse gas to the environment. Over the decades, several technologies have been developed and modified to produce hydrogen economically and sustainably from biomass. However, production from biomass, especially lignocellulosic biomass, has not kept pace with other developments in the field and still suffers from low production rates and yields. Ongoing research is expected to find a solution to the problems faced in this sector, and biohydrogen will emerge as an economical fuel in the future.
  • Article
    Biomass is the most used renewable energy source now and in future. There are two global biomass-based liquid transportation fuels that might replace gasoline and diesel fuel. These are bioethanol and biodiesel. It is generally held that biofuels offer many benefits, including sustainability, reduction of greenhouse gas emissions, and security of supply. The recent use of ethanol as fuel has increased its production. Most ethanol is currently being produced from sugar cane or from corn. Yeast is used to ferment sugars into ethanol. In the case of carbohydrates (such as corn), a pretreatment step of converting carbohydrate into sugars is needed. The advantages of biodiesel as diesel fuel are its renewability, portability, ready availability, higher combustion efficiency, higher biodegradability, non-toxicity, lower sulfur and aromatic content, higher flash point (non-flammable), and higher cetane number. The major disadvantages of biodiesel are its high price, higher viscosity, lower energy content, higher cloud point and pour point, higher nitrogen oxide emissions, lower engine speed and power, injector coking, engine compatibility, and greater engine wear. The sources of biodiesel are vegetable oils, used plant oils, and fats. Biodiesel is obtained from vegetable oils by reacting methanol using a process called transesterification. The purpose of the transesterification process is to lower the viscosity and oxygen content of the vegetable oil. The cost of biodiesels varies depending on the feedstock, geographic area, methanol prices, and seasonal variability in crop production.
  • Article
    Full-text available
    Cellulose composes most of domestic, industrial, and agricultural wastes, forest, products and indigenous plant materials valued as biomass resources. The immensity of these materials should be a driving force to efficiently exhaust them as energy sources and, in effect, offset environmental impact of wastes. This study focuses on the pyrolysis reactions of cellulose as a main component in biomass through thermal degradation of levoglucosan - an intermediate crucial to the formation of char and other products. Theoretical calculations involving DFT and MP2 methods were employed to investigate molecular and activation energies as well as verify proposed reaction mechanisms in cellulose pyrolysis. The differences between the calculated proposed structures are illustrated.
  • Article
    Full-text available
    Pyrolysis behaviors and yields of liquid products of tea waste supplied from Surmene-Trabzon Caykur Factory in The Eastern Black Sea Region of Turkey were determined catalytically. The conversion of tea waste to liquid products has been examined in the presence of alkali and metal additives at different temperatures. The pyrolysis experiments were performed in a device designed for this purpose. The main element of this device was a stainless-steel cylindrical reactor vertically-heated by an electric tubular furnace with the temperature being controlled by a simple thermocouple (Ni-Cr constantan) inside the bed. The yields of liquid product were increased with using of catalysts at the final pyrolysis temperature of 723K with respect to non-catalytic pyrolysis. At 973K, the yields of liquid were only increased with using of Na 2CO 3 catalyst, but K 2CO 3 and ZnCI 2 are not effective much on pyrolysis. The catalytic effect of K 2CO 3 was greater than that of Na 2CO 3 at 723 K and vice a versa at 973K. The liquid fraction of the pyrolysis products consists of two phases: an aqueous phase containing a wide variety of organo-oxygen compounds of low molecular weight and a non-aqueous oily bottom phase containing insoluble organics of high molecular weight. This phase is called as bio-oil or tar and is the product of greatest interest.
  • Article
    Strict exhaust emission regulations set for limiting the air pollution caused by motor vehicles have oriented the producers and researchers to investigate new techniques to reduce exhaust emissions. The main pollutants caused by diesel engines are particle matters (PM), nitrogen oxides (NO x), hydrocarbons (HC), and carbon monoxides (CO). Among the preventive actions to keep the emissions caused by motor vehicles at a certain level are enhancing the fuel quality, preventing the pollutant formation in the engine, and developing the post- combustion emission control systems. There are many different technologies used for reducing the amount of pollutants in diesel engine exhausts. In this study, the main post-combustion techniques applied for reducing these pollutants catalytically are being examined.
  • Article
    This study focuses on utilization and benefits of spherical ice capsules in district cooling systems, and describes the relevant study methods and results. Cooling carried out by means of the latent heat of ice will save on electrical energy. It will be possible to use an existing cooling system as a heating system in the winter, so that fuel will be saved on the one hand and pollution will be reduced in the other hand. Furthermore, the system's water content can be used as utility water after cooling by means of ice balls (capsules) made of snow. Thus it will be possible to obtain maximum cooling at minimum cost, to reduce pollution by a significant rate, and to obtain water. The renewable energy sources are biorenewables, hydro, solar, wind, geothermal and other energies Alternative transportation fuels are substitute fuel sources to petroleum.
  • Article
    The purpose of this study is to discuss present challenges and future prospects for production and use of biofuels as alternative energy pathways to sustainable development. The dramatic increase in the price of petroleum, the finite nature of fossil fuels, increasing concerns regarding environmental impact, especially related to greenhouse gas emissions, and health and safety considerations are forcing the search for new energy sources and alternative ways to power the world's motor vehicles. Interest in the use of biofuels worldwide has grown strongly in recent years due to the high oil prices, concerns about climate change from GHG emissions and the desire to promote domestic rural economies. Developing countries have a comparative advantage for bio-fuel production because of greater availability of land, favorable climatic conditions for agriculture and lower labor costs. In developed countries there is a growing trend towards employing modern technologies and efficient bio-energy conversion using a range of bio-fuels, which are becoming cost-wise competitive with fossil fuels.
  • Article
    The corn plant composed of stover and corncob. About 1 kg of stover is produced per kg of grain. The thermal conversion of biomass to organic liquid products can be accomplished using liquefaction and pyrolysis methods. Thermochemical conversion processes are promising means for converting corn stover into valuable products such as chemicals and fuels. The corn stover was liquefied by sub-and supercritical water extraction in an autoclave in the reaction temperature range of 610-720 K without a catalyst. The experimental results show that the yield of liquid product was significantly influenced by the process conditions. The maximum yield of liquid product was obtained at reaction temperature 680 K. The highest liquid product yield of 55.7% was obtained at reaction temperature 680 K, when reaction temperature is higher or lower than this temperature, the liquid product yield slightly decreases. The effect of temperature is highly significant on the yield of oil obtained from the liquefaction of the corn stover. The main liquefaction parameters were temperature (610-700 K), water-to-solid ratio (1:1-5:1) and liquefaction time (30-75 min).
  • Article
    Full-text available
    The amount of waste has been steadily increasing due to the increasing human population and urbanization. Waste materials are generated from manufacturing processes, industries and municipal solid wastes (MSW). The increasing awareness about the environment has tremendously contributed to the concerns related with disposal of the generated wastes. This paper presents a detailed review about waste and waste management options, and research published on the effect of waste materials on environment.
  • Article
    Future energy technology will utilize hydrogen with an increasing trend in steady, as well as unsteady, combustion processes. Hydrogen is produced from fossil fuels, hydrocarbon polymers, biomass, and water by electrolysis and from biological process by photoliticaly or thermolysis. Hydrogen is produced from solid waste by pyrolysis. In this study, three different biomass samples were subjected to direct- and catalytic pyrolysis in order to obtain hydrogen-rich gaseous products at desired temperatures. The samples, both untreated and impregnated with catalyst, were pyrolysed at 770, 925, 975 and 1025 K temperatures. The total volume and the yield of gas from both pyrolysis were found to increase with increasing temperature. The largest hydrogen-rich gas yield were obtained from olive husk, cotton cocoon shell, and tea waste using about 13% ZnCl2 as catalyst at about 1025 K temperature were 70.3, 59.9, and 60.3%, respectively. In general, in the pyrolysis of biomass, the yield of hydrogen-rich gaseous product increases with ZnCl2 catalyst, but the yield of pyrolytic gas decreased in spite of increasing the yield of charcoal and liquid products. The effect of K2CO3 and Na2CO3 as catalysts on pyrolysis depends on the biomass species. The catalytic effect of Na2CO3 was greater than that of K2CO3 for the cotton cocoon shell and tea waste, but the catalytic effect of K2CO3 was greater for the olive husk.
  • Article
    Modelling approaches of biomass steam gasification are investigated that take into account both chemical and physical kinetic limitations. The gas phase can be described by two independent reactions: (i) the steam reforming of CH4, which is kinetically limited under the operating conditions (1073 < T < 1273 K, p = 1 bar), (ii) the water–gas shift reaction, which would be close to equilibrium under the operating conditions (1073 < T < 1273 K, p = 1 bar). Concerning solid, a time scale analysis of the main phenomena has been performed. For particles of 500 lm, the transformation can be seen as two successive steps: (i) pyrolysis of biomass, which is both chemically and heat-transfer controlled; (ii) steam gasification of residue, which is chemically controlled.
  • Article
    Methane production from California landfills is estimated using a first order decay model and actual plus predicted waste disposal amounts from 1970 through 2025. Potential hydrogen production is estimated assuming 67% methane (landfill gas) recovery and upgrading and a 70% energy conversion efficiency of methane to hydrogen (higher heating value basis) using a steam reformer system. Statewide landfill derived methane is predicted to increase from 2.4 to 3.5 billion Nm3 y -1 between 2005 and 2025. For the same period, potential landfill derived hydrogen production was estimated to range from 300 to 430 Gg y-1. This hydrogen energy is equivalent to 1.3 Gl of gasoline equivalent (for 2005) or about 2% of California's gasoline usage and could fuel between 1.3 and 1.9 million fuel cell vehicles (FCV). The largest 15 landfills (in terms of current annual disposal) could potentially produce hydrogen equivalent to some 0.4 Gl of gasoline equivalent and could fuel some 500,000 FCV. The cost of landfill derived hydrogen using commercial gas upgrading and small steam methane reformer systems is estimated to be less than US$3.50 kg-1 (US$29.10 GJ-1, lower heating value), not
  • The aim of this study is to provide a global approach on liquid biofuels such as bioethanol and biodiesel, a key topic for the future of energy for transportation. The term biofuel is referred to as liquid or gaseous fuel for the transport sector that are predominantly produced from biomass. There are several reasons for biofuels to be considered as relevant technologies by both developing and industrialized countries. They include energy security reasons, environmental concerns, foreign exchange savings, and socioeconomic issues related to the rural sector. Bioethanol is a petrol additive/substitute. It is possible that wood, straw, and even household wastes may be economically converted to bioethanol. Bioethanol is derived from alcoholic fermentation of sucrose or simple sugars, which are produced from biomass by hydrolysis process. Biodiesel is an environmentally friendly alternative liquid fuel that can be used in any diesel engine without modification. There has been renewed interest in the use of vegetable oils for making biodiesel due to less pollution and its renewable nature in contrast to conventional petroleum diesel fuel.
  • Article
    An assessment of the potential availability of selected residues from maize, cassava, millet, plantain, groundnuts, sorghum, oil palm, palm kernel, and cowpeas for possible conversion to renewable energy in Nigeria has been made. It is estimated that nearly 58 million tonnes of these residues were potentially available in the year 2004 with energy potential of about 20.8 million tonnes oil equivalents. The residue availability for 2010 is projected to be about 80 million tonnes. These residues, when converted to energetically usable forms, can substitute or complement the fossil energy sources in Nigeria by more than 80%.
  • Article
    The aim of this study is to investigate gasification technologies and gasification of biomass for gaseous products. The gasification of biomass is a thermal treatment, which results in a high proportion of gaseous products and small quantities of char (solid product) and ash. At temperatures of approximately 873–1,273 K, solid biomass undergoes thermal decomposition to form gas-phase products that typically include H2, CO, CO2, CH4, H2O, and other gaseous hydrocarbons. Hydrogen gas was produced on a pilot scale by steam gasification of charred cellulosic waste material. The yield from steam gasification increases with increasing water to sample ratio. The yields of hydrogen from the pyrolysis and the steam gasification increase with the increase of temperature. In general, the gasification temperature is higher than that of pyrolysis and the yield of hydrogen from the gasification is higher than that of the pyrolysis.
  • Article
    The energy sources have been split into three categories: fossil fuels, renewable sources, and nuclear sources. Energy new and renewable resources will play an important role in the world's future. There are several reasons for biofuels to be considered as relevant technologies by both developing and industrialized countries. They include energy security reasons, environmental concerns, foreign exchange savings, and socioeconomic issues related to the rural sector. The term “modern biomass” is generally used to describe the traditional biomass use through the efficient and clean combustion technologies and sustained supply of biomass resources, environmentally sound and competitive fuels, heat, and electricity using modern conversion technologies. Modern biomass can be used for the generation of electricity and heat. Biofuels as well as green diesel produced from biomass by Fischer-Tropsch synthesis are the most modern biomass-based transportation fuels. Green diesel is a renewable replacement to petroleum-based diesel. Biomass energy conversion facilities are important for obtaining bio-oil by pyrolysis. Pyrolysis is the most important process among the thermal conversion processes of biomass. There are four different ways of modifying vegetable oils and fats for use as diesel fuel, such as pyrolysis, dilution with hydrocarbons (blending), emulsification, and transesterification.
  • Article
    Full-text available
    Biomass is a useful feed material for energy and chemical resources. Hydrothermal gasification of biomass wastes has been identified as a possible system for producing hydrogen. Supercritical and subcritical water has attracted much attention as an environmentally benign reaction medium and reactant. The main objective of this study is to assess and introduce the hydrothermal gasification of biomass wastes containing various quantities of the model compounds and real biomass. The decomposition of biomass, as a basis of hydrothermal treatment of organic wastes, is introduced. To eliminate chars and tars formation and obtain higher yields of hydrogen, catalyzed hydrothermal gasification of biomass wastes is summarized.
  • Article
    World-wide energy demand will continue to increase in the next years and Europe still has very limited home-grown resources. The European Union currently imports 50% of its demand for oil, and, if nothing is done, this figure will rise to 70% in 20–30 years time. Hydrogen and fuel cell technologies could form an integral part of future sustainable energy systems. This will contribute to improving Europe's energy security and air quality, while lessening climate change. The European Union prefers to use renewables, mainly hydrogen rather than fossil fuels, because of decreasing supply of fossil fuels and increasing demand for using renewable energy sources, especially hydrogen. Hydrogen is a clean energy vector. It can be produced from a wide variety of primary energy sources. It is possible to decarbonize fossil fuels by carbon capture, allowing for the production of hydrogen from these traditional fuels with negligible carbon emissions. But, more importantly, hydrogen produced through a range of renewable primary energy sources such as wind, biomass, and solar energy is ideal for gradually replacing fossil fuels. Some hydrogen platforms can introduce a coherent European Union strategy in order to develop the use of hydrogen and hydrogen production technologies while gaining worldwide leadership.
  • Article
    Hydrogen is a promising renewable fuel for transportation and domestic applications. Hence, in both the near term and long term, hydrogen demand is expected to increase significantly. Producing hydrogen, as well as any other synthetic fuel, will inevitably cost more energy than pumping up oil or using other fossil fuels. In this work, a review is made of the alternative technological methods that could be used to produce this fuel. Hydrogen can be generated in a number of ways, such as electrochemical processes, thermochemical processes, photochemical processes, photocatalytic processes, or photoelectrochemical processes. The thermal production process, which uses steam to produce hydrogen from natural gas or other light hydrocarbons, is most common. Steam reforming of natural gas is currently the least expensive method of producing hydrogen and is used for about half of the world's production of hydrogen. Approximately 95% of the hydrogen produced today comes from carbonaceous raw material, primarily fossil in origin.
  • Article
    The main objective in doing the present study is to investigate hydrogen production from biomass via pyrolysis and gasification. Hydrogen is currently derived from nonrenewable natural gas and petroleum but could in principle be generated from renewable resources such as biomass. It can be produced from biomass via two thermochemical processes: (1) gasification followed by reforming of the syngas, and (2) fast pyrolysis followed by reforming of the carbohydrate fraction of the bio-oil. Steam reforming of hydrocarbons, partial oxidation of heavy oil residues, selected steam reforming of aromatic compounds, and gasification of coals and solid wastes to yield a mixture of H2 and CO (syngas), followed by water-gas shift conversion to produce H2 and CO2, are well-established processes. The yields of hydrogen from the pyrolysis and the steam gasification increase with increase of temperature. In general, the gasification temperature is higher than that of pyrolysis and the yield of hydrogen from the gasification is higher than that of the pyrolysis.
  • Article
    Hydrogen is not a primary fuel. It must be manufactured from water with either fossil or nonfossil energy sources. Widespread use of hydrogen as an energy source could improve global climate change, energy efficiency, and air quality. The thermochemical conversion processes, such as pyrolysis, gasification, and steam gasification are available for converting the biomass to a more useful energy. The yield from steam gasification increases with increasing water-to-sample ratio. The yields of hydrogen from the pyrolysis and the steam gasification increase with increase of temperature. Hydrogen-powered fuel cells are an important enabling technology for the hydrogen future and more efficient alternatives to the combustion of gasoline and other fossil fuels. Hydrogen has the potential to solve two major energy problems: reducing dependence on petroleum and reducing pollution and greenhouse gas emissions.
  • Article
    As concern about global warming and dependence on fossil fuels grows, the search for renewable energy sources that reduce CO2 emissions becomes a matter of widespread attention. Production of ethanol (bioethanol) from biomass is one way to reduce both the consumption of crude oil and environmental pollution. Using bioethanol-blended fuel for automobiles can significantly reduce petroleum use and exhaust greenhouse gas emission. While more expensive to produce than other fuel types, bioethanol production boosts the farm economy. Up to 80% of production cost is the cost of feedstock. Bioethanol can be produced from cellulose feedstocks such as corn stalks, rice straw, sugar cane bagasse, pulpwood, switchgrass, and municipal solid waste.
  • Article
    The pyrolysis of biomass is a promising route for the production of solid (charcoal), liquid (tar and other organics), and gaseous products. These products are of interest as they are possible alternate sources of fuels and chemicals. The most interesting temperature range for the production of the pyrolysis products is between 625 and 775 K. The charcoal yield decreases as the temperature increases. Liquid products from biomass pyrolysis are maximum at temperatures between 625 and 725 K.
  • Article
    The aim of this study was to assess the scientific and engineering advancements of producing hydrogen from biomass via two thermochemical processes: (a) conventional pyrolysis followed by reforming of the carbohydrate fraction of the bio-oil and (b) gasification followed by reforming of the syngas (H2 + CO). The yield from steam gasification increases with increasing water-to-sample ratio. The yields of hydrogen from the pyrolysis and the steam gasification increase with increasing of temperature. In general, the gasification temperature is higher than that of pyrolysis and the yield of hydrogen from the gasification is higher than that of the pyrolysis. The highest yields (% dry and ash free basis) were obtained from the pyrolysis (46%) and steam gasification (55%) of wheat straw while the lowest yields from olive waste. The yield of hydrogen from supercritical water extraction was considerably high (49%) at lower temperatures. The pyrolysis was carried out at the moderate temperatures and steam gasification at the highest temperatures. This study demonstrates that hydrogen can be produced economically from biomass. The pyrolysis-based technology, in particular, because it has coproduct opportunities, has the most favorable economics.
  • Article
    Hydrogen is the fuel of the future mainly due to its high conversion efficiency, recyclability and nonpolluting nature. Biological hydrogen production processes are found to be more environment friendly and less energy intensive as compared to thermochemical and electrochemical processes. They are mostly controlled by either photosynthetic or fermentative organisms. Till today, more emphasis has been given on the former processes. Nitrogenase and hydrogenase play very important role. Genetic manipulation of cyanobacteria (hydrogenase negative gene) improves the hydrogen generation. The paper presents a survey of biological hydrogen production processes. The microorganisms and biochemical pathways involved in hydrogen generation processes are presented in some detail. Several developmental works are discussed. Immobilized system is found suitable for the continuous hydrogen production. About 28% of energy can be recovered in the form of hydrogen using sucrose as substrate. Fermentative hydrogen production processes have some edge over the other biological processes.
  • Article
    This study deals with understanding the pyrolysis decomposition mechanism of newspaper and its conversion into gaseous fuel. To know the nature of decomposition, thermogravimetric and differential thermal analyses have been performed at the heating rates of 5, 10, and 20 K/min under a nitrogen environment. Thermal degradation characteristics and the kinetic parameters (order of reaction, activation energy, and pre-exponential factor) have been determined from the thermogravimetric curves. Finally, gasification of newspaper is performed in an oxygen-free environment at different temperatures and heat-keeping times, defined as the time with a constant temperature in the reactor and the produced gases have been analyzed in a gas chromatograph. It is observed that temperature and heat-keeping time have significant effect on the compositions of gases generated from pyrolysis of newspaper.
  • Article
    Cotton stalks mill were converted to liquid products by using organic solvents (methanol, 1-butanol, and 2-butanol) with catalysts (5 or 10% borax or ulexite) and without catalyst in an autoclave at temperatures of 540, 560, and 580 K. The liquid products were extracted by liquid-liquid extraction (benzene and diethyl ether). The yields from supercritical methanol (10% borax), 1-butanol (10% borax), and 2-butanol (10% borax) conversions were 54.1, 66.8, and 28.0 (at 580 K), respectively. In the noncatalytic run with methanol was 37.4 at the same temperature.
  • Article
    Gasification as a thermochemical process is defined and limited to combustion and pyrolysis. The gasification of biomass is a thermal treatment which results in a high proportion of gaseous products and small quantities of char (solid product) and ash. Biomass gasification technologies have historically been based upon partial oxidation or partial combustion principles, resulting in the production of a hot, dirty, low Btu gas that must be directly ducted into boilers or dryers. In addition to limiting applications and often compounding environmental problems, these technologies are an inefficient source of usable energy. The main objective of the present study is to investigate gasification mechanisms of biomass structural constituents. Complete gasification of biomass involves several sequential and parallel reactions. Most of these reactions are endothermic and must be balanced by partial combustion of gas or an external heat source.
  • Article
    The catalytic steam reforming of model biomass tar, toluene being a major component, was performed at various conditions of temperature, steam injection rate, catalyst size, and space time. Two kinds of nickel-based commercial catalyst, the Katalco 46-3Q and the Katalco 46-6Q, were evaluated and compared with dolomite catalyst. Production of hydrogen generally increased with reaction temperature, steam injection rate and space time and decreased with catalyst size. In particular, zirconia-promoted nickel-based catalyst, Katalco 46-6Q, showed a higher tar conversion efficiency and shows 100% conversion even relatively lower temperature conditions of 600°C. Apparent activation energy was estimated to 94 and 57kJ/mol for dolomite and nickel-based catalyst respectively.
  • Article
    Using thermochemical calculations in the system Na-C-H-O, it is shown that when used in appropriate molar proportions carbon or methane, water and sodium hydroxide react to produce almost pure hydrogen and solid sodium carbonate. At 1 atm, the reaction takes place over a wide range of temperatures (100-800degreesC) producing hydrogen with only traces of other hydrocarbon impurities. Sodium carbonate is the byproduct of the reaction. (C) 2002 Published by Elsevier Science Ltd on behalf of the International Association for Hydrogen Energy.
  • Article
    Milestone report summarizing the economic feasibility of producing hydrogen from biomass via (1) gasification/reforming of the resulting syngas and (2) fast pyrolysis/reforming of the resulting bio-oil. Hydrogen has the potential to be a clean alternative to the fossil fuels currently used in the transportation sector. This is especially true if the hydrogen is manufactured from renewable resources, primarily sunlight, wind, and biomass. Analyses have been conducted to assess the economic feasibility of producing hydrogen from biomass via two thermochemical processes: (1) gasification followed by reforming of the syngas, and (2) fast pyrolysis followed by reforming of the carbohydrate fraction of the bio-oil. This study was conducted to update previous analyses of these processes in order to include recent experimental advances and any changes in direction from previous analyses. The systems examined were gasification in the Battelle/FERCO low pressure indirectly-heated gasifier followed by steam reforming, gasification in the Institute of Gas Technology (IGT) high pressure direct-fired gasifier followed by steam reforming, and pyrolysis followed by coproduct separation and steam reforming. In each process, water-gas shift is used to convert the reformed gas into hydrogen, and pressure swing adsorption is used to purify the product. The delivered cost of hydrogen, as well as the plant gate hydrogen selling price, were determined. All analyses included Latin Hypercube sampling to obtain a detailed sensitivity analysis.
  • Article
    Full-text available
    An evaluation of the production of agricultural residues in Turkey and their conversion to electrical energy via gasification was realized. Agricultural residues were classified into two main categories. The residues in the category A were separated into two sub groups. The residues in the subgroup A1 generally consisted of straw, plant stems, and leaves while the subgroup A2 consisted of pruning residues of fruit trees. Nearly 43 mt/yr residues are produced in category A, or dry basis. As to the subcategories, 10.8 mt/yr residues are produced in the subcategory A1 on dry basis, since 28% of the residues in this category are not utilized; approximately 3.2 mt/yr residues are produced in the subcategory A2, since 80% of the pruning residues in this category are not utilized. The processed product residues in the category B were classified into three subcategories. The subcategory B1 comprises the residues in oil production (i.e., stone, shell), the subcategory B2 comprises the residues resulting from fruit processing (i.e., stalk, peel, stone), whereas the subcategory B3 consists of the residues such as peel, seed, and husk (in tomato and rice). The highest residue quantity in the subcategory B1 was in sunflower in the form of shell with 157.6 thousand tons, the highest residue quantity in B2 subcategory was in grape with 423.0 thousand tons (in the forms of stalk, peel, and stone); in subcategory B3, the highest residue quantity was in tomato (in the forms of peel and seed) with 134.0 thousand tons. Nearly 17% of the national electricity consumption can be met if all of the unused residues (15.3 mt/yr) are converted into energy. One may say that the regions Marmara, Mediterranean, Aegean, and Central South are the suitable regions for electricity, since these are the agricultural regions having the highest intensity of unusable agricultural residues (28.0–43.2 t/km).
  • Article
    Products from lignicellulosic materials by degradation processes are reviewed based on the results of some investigations. Biomass provides a potential source of added value chemicals, such as reducing sugars, furfural, ethanol and other products by using biochemical or chemical and thermochemical. The initial degradation reactions include depolymerization, hydrolysis, oxidation, dehydration, and decarboxylation. The gas phase of pyrolitic degradation products contain mostly carbon monoxide and carbon dioxide, and minor proportions of hydrogen, methane, ethane, and propane. The liquid fraction consists mainly of water, with small proportions of acetaldehyde, propion aldehyde, butiraldehyde, acrolein, croton-aldehyde, furan, acetone, butanedione, and methanol. There are many studies on biomass conversion methods because of energy problems and environmental pollution. Ethanol is an alcohol and is fermented from sugars, starches or from lignocellulosic biomass. In order to produce bioethanol from lignocellulosic biomass, a pretreatment process is used to reduce the sample size, degrade the hemicelluloses to sugars, and open up the structure of the cellulose component. The cellulose portion is hydrolyzed by acids or enzymes into glucose sugar that is fermented to bioethanol. The sugars from the hemicelluloses are also fermented to bioethanol.
  • Article
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    In this study, sawdust samples from poplar wood were liquefied by using glycerol and alkaline glycerol in the presence of 5% Na2CO3 and 5% NaOH at different temperatures: 440, 460, 480, 500, 520, 540, and 560 K. Byproducts from the liquefaction processes of the samples mainly included lignin and carbohydrate degradation products. The degradation of lignin (delignification) occurs at lower temperatures than carbohydrates. The degradation products have fuel values. The yield of total liquefaction increases with increasing reaction temperature.
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    Biofuels are liquid fuels which can be produced from agricultural biomass. Agriculture-based biofuels include bioethanol, biodiesel, biomethanol, methane, and bio-oil components. Various agricultural residues, such as grain dust, crop residues, and fruit tree residues, are available as the sources of agricultural energy. Bio-energy from biomass, both residues and energy crops, can be converted into modern energy carriers. Bioethanol is derived from renewable sources feedstock, which are typically plants such as wheat, sugar beet, corn, straw, and wood. Biodiesel is a non-fossil fuel alternative to petrodiesel which can be obtained from vegetable oil and animal fats by transesterification. Bio-oils are liquid or gaseous fuels made from biomass materials, such as agricultural crops, municipal wastes, and agricultural and forestry by-products via biochemical or thermochemical processes.
  • Hydrogen is not a primary fuel; it must be manufactured from water with either fossil or nonfossil energy sources. Benefits include cleaner air, cleaner water, and better health. Hydrogen can be used as a engine fuel, whereas neither nuclear nor solar energy can be used directly. It has good properties as a fuel for internal combustion engines in automobiles. The main disadvantages of using hydrogen as a fuel for automobiles are huge on-board storage tanks which are required because of hydrogen's extremely low density. Hydrogen will also solve air pollution and planet-warming problems in the future. The combustion of hydrogen does not produce CO2, CO, SO2, VOC and particles, but entails emission of vapor and NOx.
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    Pyrolysis of lignocellulosic biomass and reforming of the pyroligneous oils are being studied as a strategy for producing hydrogen. A process of this nature has the potential to be cost competitive with conventional means of producing hydrogen. We propose a regionalized system of hydrogen production, where small- and medium-sized pyrolysis units (<500 Mg/day) provide bio-oil to a central reforming unit to be catalytically converted to H2 and CO2. Thermodynamic modeling of the major constituents of the bio-oil has shown that reforming is possible within a wide range of temperatures and steam-to-carbon ratios. In addition, screening tests aimed at catalytic reforming of model compounds to hydrogen using Ni-based catalysts have achieved essentially complete conversion to H2. Existing data on the catalytic reforming of oxygenates have been studied to guide catalyst selection. A process diagram for the pyrolysis and reforming operations is discussed, as are initial production cost estimates. A window of opportunity clearly exists if the bio-oil is first refined to yield valuable oxygenates so that only a residual fraction is used for hydrogen production.
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    Hydrogen production from biomass was investigated using an integrated biological and thermochemical process. Glucose was used as a biomass surrogate and was first converted to ethanol in a fermentation process. The fermentation experiments were carried out using Saccharomyces cerevisiae. The fermentation broth was then used in aqueous phase reforming (APR) over a platinum-based catalyst. An economic analysis of the proposed process demonstrates the economic viability of producing hydrogen from biomass using fermentation combined with APR. The average production yield of hydrogen was 25%. The hydrogen obtained from APR of the fermentation broth was compared against the yield from a feed containing 5% ethanol in water. While the catalyst was stable for an extended time on stream during APR of ethanol, very rapid deactivation was observed during APR of fermentation broth. Different catalyst characterization techniques, including XRD, BET surface area, and ICP-AES, were employed to investigate the causes of catalyst deactivation. Although the analysis suggested similar catalyst changes in both cases, and the exact deactivation mechanism could not be concluded, these techniques helped to eliminate some mechanisms while suggesting other possible deactivation routes. Nanofiltration of the fermentation broth was shown to remove the impurities leading to deactivation.
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    A bisphenol A based epoxy adhesive (EP) was modified by polyblending with Kraft Lignin (L). A systematic investigation of the thermally cured EP-L polyblends with up to 40% by weight L was undertaken. Adhesive shear tests, differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and solid-state CP-MAS NMR spectroscopy were performed to establish the effect of L on the mechanical properties of the polyblends and on the morphology of these crosslinked structures. The possibility of an enhanced degree of bonding between L and the EP network is discussed. This bonding can arise from a chemical reaction between L and some unreacted amine groups present in the hardener.
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    Conversion of agricultural residues to usable energy forms has gained much interest recently due to increase in energy cost as well as greater pressure on the environment by the use of fossil fuel. Thermochemical conversion processes such as pyrolysis and gasification are some of the promising options that may be applied to effectively utilize agricultural wastes as a source for energy production. In this work, an experimental research concerning biomass pyrolysis was carried out in a fixed-bed reactor in order to evaluate the thermochemical conversion process which yields value added materials, especially in form of fuel products, from agricultural by product. Jatropha Curcas Linn (physic nut) waste was chosen as a biomass material due to its anticipated large surplus in the near future. The effect of temperature, heating rate, and hold time on product distribution was investigated using thermogravimetric analysis (TGA) and quartz tube pyrolyzer. From TGA under pyrolysis condition, maximum weight losses occur between 250 and 450°C with several parallel and simultaneous decomposition steps. Fast pyrolysis trials indicated that a rise in temperature leads to increasing gas yields from 12.9 to 30.1% while decreasing liquid and char yields from 23.2 to 13.3% and 63.9 to 56.5%, respectively. High hydrogen concentration in product gas was also achieved at high temperature with reduction of other hydrocarbon gases.
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    In this study, gas and liquid fuels from biomass by steam reforming were investigated. The steam reforming process provides the opportunity to convert renewable biomass materials into clean fuel gases or synthesis gases. Synthesis gas includes mainly hydrogen and carbon monoxide which is also called as syngas (H 2 C CO). Bio-syngas is a gas rich in CO and H 2 obtained by gasification of biomass. The aim of Fischer-Tropsch Synthesis (FTS) is synthesis of long-chain hy-drocarbons from CO and H 2 gas mixture. The products from FTS are mainly aliphatic straight-chain hydrocarbons (C x H y). The distribution of the products depends on the catalyst and the process parameters such as temperature, pressure, and residence time. Typical operation conditions for the FTS are a temperature range of 475–625 K and pressures of 15–40 bar, depending on the process.