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Publications (59)
The present study aims to assess the potential exploitation of marine macroalgae waste using a cascade biorefinery approach. For that, biomass was collected from a northern Portugal beach, two different drying processes were employed (freeze-drying (FD) and sun-drying (SD)) and cascade extractions were conducted to obtain several extracts (fatty ac...
Rice is one of the most consumed cereals in the world. From rice processing, rice bran is obtained, and only a part of this by-product is effectively used. Rice bran oil can be obtained and used as an alternative feedstock for biodiesel production, although few studies exist to support its exploitation. In addition, pretreatment is required to redu...
Marine macroalgae waste (MMW) was used at different mixing ratios with fruit waste (FW) to evaluate the potential of co-digestion in enhancing methane yield. The process was conducted at mesophilic conditions (37 °C) with a fixed amount of biomass (10 g, 3.5% TS) and inoculum (150 mL; digested sewage sludge) and using MMW:FW ratios from 40:60 to 70...
The accumulation of Marine Macroalgal Waste (MMW) - drifted marine macroalgae - is a growing phenomenon. The lack of appropriate management protocols for this residual biomass leaves it mostly unmanaged or disposed of in landfills. Such inappropriate solutions lead to negative environmental impacts, health concerns and coastal degradation, represen...
In the present study, a leaner process for recovering zinc from spent alkaline batteries is studied at a laboratory scale. Such process is part of a diagram, under development, that aims at maximizing the value of all the battery components while reducing the costs of treatment and the environmental footprint involved in recycling this waste. It st...
In the present study, Marine Macroalgae Waste (MMW) biomass, mainly composed of Saccorhiza polyschides, collected from the seashore in northern Portugal, was characterized and seed germination was performed to evaluate the potential of re-exploiting this biomass for agricultural purposes. Kale (Brassica oleracea L) and parsnip (Pastinaca sativa) se...
Modelling the conversion of residual biomass to renewable fuels is of high relevance to promote the development of effective technological solutions. The present study compares the performance of five different kinetic models (pseudo-first-order kinetics, logistics, modified Gompertz, double-Gompertz, and multi-Gompertz) to describe the cumulative...
In the present study, marine macroalgae waste, mainly composed by Saccorhiza polyschides, was collected from a beach in northern Portugal and evaluated as feedstock for anaerobic digestion. Batch experiments (500 mL flasks, 300 mL working volume) were conducted at the following conditions: mesophilic temperature (37 °C); 80 rpm stirring speed; 150...
The use of seaweeds in wastewater treatment (WWT) is increasing around the world, being one of the most employed biotic systems to reduce the nutrient eutrophication pressure caused by wastewater. However, the physicochemical characteristics of the seaweeds used in the WWT limit their commercialization. Consequently, this biomass is mainly discharg...
Marine macroalgae waste was fully characterised considering the raw biomass as well as the extracted lipids and the remaining solid fraction, to provide information concerning the potential of these products to be incorporated in the economic sector. The characterisation of the biomass before (S1) and after (S2) oil extraction showed minor differen...
The present chapter provides an overview of the challenges associated with the food chain, particularly in the wine sector. It starts from a global context on the food chain (Sect. 1.2), food loss, and food waste (Sect. 1.3) and stresses out circular supply chain management (Sect. 1.4). Then, circular practices in the food supply chain and the wine...
With the purpose to compete with the homogeneous catalytic biodiesel production, a highly efficient bimetallic solid catalyst with high exposed surface, high basicity, and reusable throughout several reaction cycles, was developed by doping SBA-15 with sodium and cerium in different concentrations. The catalyst with 5 wt% of sodium and 20 wt% of ce...
Portugal’s performance concerning the Refuse Derived Fuel (RDF) strategy, with particular focus on perspectives for the Northern Region based on the current status of integrated municipal waste management systems in that region, was evaluated. Legal documents, official reports and the market were analyzed. The 2015 national installed capacity of wa...
Con el fin de producir biodiesel mediante catálisis heterogénea, se sintetizaron catalizadores sólidos de carácter básico y ácido, a base de sodio y cerio soportados sobre SBA-15. Los sólidos obtenidos se caracterizaron por difracción de rayos X a bajo y alto ángulo, método BET, desorción a temperatura programada de dióxido de carbono y análisis FT...
The reduction of food losses and food waste generation are a huge challenge, which demand the optimal use of food resources. This study shows how two different countries / markets face this issue through the normative aspect. Both contexts (Portugal and Brazil) present a close re-lationship with global agendas. However, the European Union has alrea...
The present study evaluated biodiesel production using Layered Double Hydroxides (LDHs) and derived mixed oxides as heterogeneous catalysts to analyse the relation between the physicochemical and textural properties of these materials with biodiesel yield. Experimental planning was conducted to evaluate the effect of different Mg/Al molar ratios, p...
Recent research focuses on new biodiesel production and purification technologies that seek a carbon-neutral footprint, as well as cheap, renewable and abundant raw materials that do not compete with the demand for food. Then, many attractive alternatives arise due to their availability or low-cost, such as used cooking oil, Jatropha oil (non-edibl...
Enzymatic hydroesterification is a heterogeneous catalyzed process suitable for the conversion of low-cost feedstocks in biodiesel production, namely, because of its tolerance to high free fatty acid contents. The current study describes the use of Fourier transform infrared spectroscopy (FTIR) to monitor biodiesel production using enzymatic hydroe...
Objectives
To identify, by a systematic literature review, how the wine sector has incorporated Circular Economy in its activities.
Biodiesel is usually produced from edible oils which compete with the food market. Crambe abyssinica is a non-food crop referred as having high potential for biodiesel production. An entire cycle of seeding, harvesting, oil extraction and biodiesel production was performed with Crambe; probably, the first study carried out with this specie in Portu...
Purpose
Biodiesel is a renewable fuel that can be mixed with toluene and be accidentally released into anoxic ecosystems and impact soil microbial communities. Therefore, the aim of the present work was to examine, under nitrate-reduction conditions, the biodegradation of toluene in the presence of two different types of biodiesel (sunflower and ra...
Glycerol, ethylene glycol and quicklime were used as alternative dehydrating agents to obtain anhydrous bioethanol from sweet potato. The assay conditions were standardized at 76 °C, 600 mbar, 30 rpm and 1 h, using 88.0 and 94.0 °GL bioethanol grades. For organic reagents, three volumetric ratios were studied (0.25, 0.50 and 0.75 V/V) whereas for q...
34 GVEXECUTIVO • V 17 • N 5 • SET/OUT 2018 • FUNDAÇÃO GETULIO VARGAS A | SUSTENTABILIDADE • O MERCADO DA ECONOMIA CIRCULAR D esde a Revolução Industrial, o modelo eco-nômico dominante baseou-se no fluxo linear de extração, processamento e transformação de matéria-prima em bens, seu consumo e descarte. Como o pressuposto da constan-te oferta de recu...
In the design of catalysts, an extremely important point is to determine, control and increase the availability of active sites on the surface. In the present work, active sodium oxide species have been identified and it is demonstrated how its dispersion can be suitably improved by combining sodium loading degree and calcination heating rate in or...
The recovery of electronic waste to obtain secondary raw materials is a subject of high relevance in the context of circular economy. Accordingly, the present work relies on the evaluation of mining separation/concentration techniques (comminution, size screening, magnetic separation and gravity concentration) alone as well as combined with thermal...
The present study provides an overview on municipal waste management in Portugal, with fo-cus on current status of Refuse Derived Fuel Recovery (RDF), forecasts set by the National strategy and 2020 targets. Considering the official reports on municipal waste management and related legislation, although the capacity (considering MT and MBT) would a...
In the present study, the effect of different degumming processes on the phosphorus content of Crambe abyssinica oil and resultant biodiesel was evaluated. The non-edible oil was submitted to water degumming and chemical degumming with different concentrations of phosphoric acid and varying the acid to oil volume percentages. Phosphorus content of...
The present study evaluated a pilot scale project’s impact - “Bioenergy in São Tomé and Príncipe
(STP)”, to install small anaerobic digesters - on greenhouse gases emissions. At STP, wood
is a subsistence fuel source and it is imperative to develop more sustainable alternatives to it and
for waste management. For this study, 3 communities were chos...
The enzymatic esterification of an acid waste oil was investigated using a commercial lipase (Thermomyces lanuginosus) in batch reactors, under the following reaction conditions: temperature of 35 °C, molar ratio of acid:alcohol of 1:1.5, vigorous magnetic stirring and enzyme concentration from 2 to 5 wt.%. The reaction progressed during 24 h. The...
The aim of the present work was to study the anaerobic biodegradation of benzene in the presence of ethylic and methylic biodiesel. Biodiesel was produced by methanolysis and ethanolysis of virgin sunflower oil and ethanolysis of waste frying oil, and further characterized according to the European Biodiesel Standard EN 14214 for water content, fat...
Waste management is a relevant issue, which should consider the assumptions of circular economy and their alignment with principles of Sustainable Development. In Europe, the waste management agenda is constantly being discussed and undergoes periodic review processes to better adapt the legislation and therefore improve the practices at the member...
The present study evaluated the recycling of crude glycerol as source of
catalyst for biodiesel production. For that purpose, two sets of experiments
were conducted. In the first set (A), biodiesel was synthesized by
conventional methanolysis of sunflower oil using NaOH as catalyst at 65°C
during 1 h and varying catalyst concentration (0.4 - 1.2 wt...
The increasing use of biofuels as additives to gasoline may have potential indirect effects on the efficiency of soil remediation technologies used to remediate fuel spills. This problem has not yet been studied. Sorption is one of the controlling processes in soil remediation. The effect of biofuels on sorption and phase distribution of contaminan...
In the present work,Jatropha curcas biodiesel was produced from a high free fatty acid raw oil (AV = 3536 mg KOH g(-1)) containing 76.5% w/w of unsaturated fatty acids. The production route consisted of a two-step method, using acid esterification, followed by conventional alkali methanolysis. Biodiesel was characterized in agreement with EN 14214:...
The production of natural and synthetic rubber/waste – EVA (Ethylene-Vinyl Acetate) composites was performed using natural rubber, styrene-butadiene rubber or acrylonitrile-butadiene rubber and 10–20 parts per hundred rubber (phr) of waste. Several physical and mechanical properties of the composites were further determined according to the require...
In the present work, biodiesel production using a glycerol enriched heterogeneous catalyst was studied.
For that purpose, the catalyst performance at different glycerol concentrations and reaction conditions
(under ambient atmosphere) was evaluated and two triglyceride sources were used. The most active catalyst
was produced using CaO, glycerol and...
In the present research work, different types of biodiesel were produced by a homogeneous alkali transesterification reaction using soybean oil, pork lard, and castor bean oil as raw materials, to evaluate how their different compositions may affect the biodegradability, namely, in the presence of benzene. Biodiesel was characterized according to t...
No studies are reported on ethylic biodiesel integrated processes, considering raw materials, reaction optimization and product purification. The present study aims to: i) select key variables for experimental optimization of ethanolysis using a virgin vegetable oil; ii) perform an optimization study using a waste oil; and iii) evaluate the effecti...
The technologies conventionally used for biodiesel purification imply high consumptions of both energy and water. In the present work, biodiesel was produced by transesterification using a very active calcium glyceroxide catalyst and purified using water-free processes. The study focused on soaps removal that was the main product impurity. The best...
The present study evaluated biodiesel production using oil extracted from fish canning industry wastes, focusing on pre-treatment and reaction conditions. Experimental planning was conducted to evaluate the influence of acid catalyst concentration (1–3 wt.% H2SO4) in the esterification pre-treatment and the amount of methanolic solution (60–90 vol....
A preliminary assessment of castor plant adaptability at Northern Portugal was performed, together with the evaluation of the extracted raw oil, without any refinement, for biodiesel production. Castor was seeded, plants grew and seeds were manually harvested after 2 years. Mechanical and chemical oil extraction procedures were evaluated. Biodiesel...
The use of heterogeneous catalysts for biodiesel production aims to simplify the production process as well as to reduce purification costs and related environmental impacts. Calcium manganese oxide was recently identified by the authors as an interesting heterogeneous catalyst for biodiesel production from animal fat; however, the difference betwe...
The main objective of this study was to list and compare the advantages and disadvantages of different methodologies to modify the surface of activated carbons (ACs) for their application as adsorbents to remove organic and inorganic pollutants from aqueous phase. These methodologies have been categorized into four broad groups: oxidation, sulfurat...
In order to contribute for a more sustainable biodiesel production, its synthesis from animal fat through heterogeneous catalysis was studied, by focusing on: (i) selecting a heterogeneous catalyst for pork lard transesterification; (ii) studying the influence of the reaction conditions on biodiesel purity, namely by using response surface methodol...
Intensive research around the use of activated carbons for water and wastewater treatment purposes has been made for decades. The main objective of the present review was to analyse the specific application of activated carbons in landfill leachate treatment. As leachates are normally very complex matrixes, their treatment using activated carbons i...
Biodiesel is an alternative fuel to fossil diesel whose major disadvantage is the dubious economical viability of the production process, due to the high raw material costs. In the work here reported, biodiesel was produced from poultry fat, a potentially good alternative raw material due to its low price and availability. The specific objectives o...
The objective of the present work was: (i) to enable biodiesel production from acid waste lard; (ii) to study the esterification reaction as possible pre-treatment at different temperatures, catalyst amount and reaction times; (iii) to evaluate biodiesel quality according to EN 14214 after basic transesterification of the pre-treated fat; and (iv)...
A large amount of studies might be found regarding the improvement of biodiesel production; however, there is a lack of information concerning both, the simultaneous comparison of the catalyst performance for different raw materials, and the final product quality. Therefore, the objective of the present study was to evaluate: (i) the biodiesel synt...
Studying alternative raw materials for biodiesel production is of major importance. The use of mixtures, namely, by incorporating wastes, is an environmental friendly alternative and might reduce production costs. The objective of the present work was (i) to study biodiesel production using vegetable oils (virgin and waste) mixed with animal fat, (...
Commercial activated carbon is a preferred adsorbent for the removal of micropollutants from the aqueous phase; however, its widespread use is restricted due to high associated costs. To decrease treatment costs, attempts have been made to find inexpensive alternative activated carbon (AC) precursors, such as waste materials. Some reviews report th...
