Hydrotreating of waste cooking oil for biodiesel production. Part I: Effect of temperature on product yields and heteroatom removal

Chemical Process Engineering Research Institute - CPERI, Centre for Research and Technology Hellas - CERTH, Thermi-Thessaloniki, Greece.
Bioresource Technology (Impact Factor: 5.04). 09/2010; 101(17):6651-6. DOI: 10.1016/j.biortech.2010.03.081
Source: PubMed

ABSTRACT Hydrotreating of waste cooking oil (WCO) was studied as a process for biofuels production. The hydrotreatment temperature is the most dominant operating parameter which defines catalyst performance as well as catalyst life. In this analysis, a hydrotreating temperature range of 330-398 degrees C was explored via a series of five experiments (330, 350, 370, 385 and 398 degrees C). Several parameters were considered for evaluating the effect of temperature including product yields, conversion, selectivity (diesel and gasoline), heteroatom removal (sulfur, nitrogen and oxygen) and saturation of double bonds. For all experiments the same commercial hydrotreating catalyst was utilized, while the remaining operating parameters were constant (pressure=1200 psig, LHSV=1.0 h(-1), H(2)/oil ratio=4000 scfb, liquid feed=0.33 ml/min and gas feed=0.4 scfh). It was observed that higher reactor temperatures are more attractive when gasoline production is of interest, while lower reaction temperatures are more suitable when diesel production is more important.

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Available from: Stella Bezergianni, Mar 04, 2014
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    • "Although oil, coal and natural gas cover most of the world energy needs, nevertheless these fuels are not considered sustainable and are also questionable from an economic, ecological and environmental point of view. The recent volatility in petroleum prices and the growing awareness related to the clean environment have stimulated the recent interest in alternative energy sources [2] [3]. "
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    ABSTRACT: Production of biodiesel from non-edible vegetable oils is of paramount significance in India due to inadequate edible oil production and primary focus for biodiesel feedstock in the country has been confined to Jatropha curcas only. On the contrary, India has a diverse basket of non-edible oil crops with substantial potential for commercial scale biodiesel production. In this context, the present research work deals with a relatively unexplored and underutilized non-edible vegetable oil “Schleichera oleosa” or “Kusum oil”. The plant has presence throughout the Indian sub-continent with special penetration in rural and tribal dominated remote locations. The kusum biodiesel (KB) was produced using a two stage esterification cum transesterification process on account of the high free fatty acid (FFA) contents of the oil. In the esterification stage, 0.85% by mass of catalyst (Paratoluene sulfonic acid), 60°C temperature under constant agitation at 450 rpm led to less than 2% FFA in 45 minutes. Similarly, the transesterification stage led to 97.2% ester yield with 1.4% by mass of catalyst (potassium hydroxide), 65°C temperature and 100 minutes time with 450 rpm agitation. Important physico-chemical properties like density, viscosity, heating value, cold flow properties and oxidation stability of KB were evaluated and found within limits of corresponding ASTM/EN standards. The fatty acid profile suggests that oleic acid (18:1) is the major fatty acid present in the oil. Various blends were prepared for the engine trial by blending 10%, 20%, 30% and 40% of KB in mineral diesel on volume basis and were named as KB10, KB20, KB30 and KB40 respectively. The results of the experimental trial indicated that the total combustion duration (TCD) in case of KB10 and KB20 were 19 and 20 crank angle degrees (CAD) respectively where as KB30 and KB40 showed 23 and 26 CAD as compared to 21 CAD exhibited by the diesel baseline (D100). Interestingly, the diffusion phase combustion duration as a fraction of TCD was found to increase from roughly 55% for D100 to 65% for KB40 indicating smoother engine operation with increased KB composition in the test fuel. Ignition delay of the test fuels were reduced with increase in KB volume fraction on account of higher cetane rating of KB. The cumulative heat release (CHR) per cycle was 1200.97 and 1194.2 Joules for KB10 and KB20 respectively as compared to 1105.8 Joules exhibited by D100. However, the higher blends exhibited lower CHR compared to D100. Similarly, the peak in-cylinder pressure of KB10 and KB20 was found to be higher than the diesel baseline whereas the other higher blends indicated 4-7% reduction as compared to D100 operation. Hydrocarbons and carbon monoxide emissions along with smoke opacity at full load were reduced by 7-25 % where as emissions of oxides of nitrogen were increased by a moderate margin of 4-12% as compared to baseline data. KB10, KB20 and KB30 exhibited higher full load brake thermal efficiency (BTE) where as KB40 indicated a marginal drop as compared to the neat diesel operation.
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    • "Oils obtained from special breeding non edible hybrids like rapeseed oil with high euric acid content on non sulphided CoMo/Al2O3 catalyst (Solymosi et al, 2011a) and sunflower and rapeseed oil with high oleic acid content on CoMo/Al2O3 catalyst (Solymosi et al, 2011b).Motor fuel purpose hydrogenation of animal fats or waste triglycerides were investigated on NiMo/Al2O3 (Baladincz et al, 2010), CoMo/Al2O3 sulphided catalysts and Pt/Pd/USY (Baladincz et al, 2011,). Bezergianni et al (2010a) investigated the hydroconversion of used cooking oil including the product yields and reaction routes (Bezergianni et al, 2010b). Consequently, production of second generation bio fuels from alternative sources (mainly hydrotreated vegetable oils) is widely investigated. "
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    ABSTRACT: The liquid motorfuels are the main power source both of the commercial and public transportation. Renewable fuels can play significant role to achieve the EU's plan, to reach the 10 % energy ratio of total fuel consumption until 2020. To achieve all this goals the European Union created the 2003/30/EC and further the 2009/28/EC directives. Unconventional feedstocks were investigated, for example non edible hybrids of oilseed plants such as rapeseed oils with high euric acid content or sunflower oils with high oleic acid content, used cooking oil. Beside the sustainability and the technical compatibility of these compounds with the current engine and vehicle constructions should be ensure, thus this bio components can be blend in the motor fuels unlimited quantity. The maximum amount of bio-component can be applied in motor fuels is 10 % bio-ethanol in gasoline and 7 % fatty acid-methyl-ester in diesel fuel. In this context heterogen catalytic hydrogenation of used cooking oil was studied on aluminium-oxide supported transition metal catalyst. The applied operation parameters were the following: temperature; 320 -380 °C, pressure: 20 -80 bar, LHSV: 1.0 h -1 , H2/hydrocarbon ratio: 600 Nm 3 /m 3 . The yield of products in gas oil boiling range at the favourable operation parameters was close to the theoretical value (80–90%). Quality parameters of these products were the following; the cetane number was higher than 75, the aromatic content was lower than 0.1 % and the sulphur content was lower than 5 mg/kg. The actual EN 590:2009 +A1 2010 standard does not limit the blending ratio of these bio-components, the blending of biodiesel is limited (max 7 v/v%). Consequently these products can be blended in gasoil up to 10 %, and this way we can meet the requirements of the EU which prescribe at least 10-80 % bio component blending in motor fuels by 2020.
    PRES 2013, Rhodes; 09/2013
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    • "Secondly, the operating parameters of hydrotreating WCO (reaction temperature, pressure, liquid hourly space velocity, and hydrogen-to-WCO ratio) had to be optimized. A series of experiments were conducted in order to evaluate the optimal operating parameters that will maximize the desired product (biodiesel) yield (Bezergianni et al. 2010a,b, 2011). "
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    ABSTRACT: Conceiving, exploring, and exploiting new ideas are the basis for technological creativity and innovation. By far, the most important step is the conception of a new idea having the potential to be transformed to a successful business solution. Nevertheless, the exploration of a new idea and its subsequent exploitation require both recourses and systematic planning in order to promote a sustainable entrepreneurship. An innovative idea of a new green technology for producing diesel from residual feedstocks was conceived and developed in the Centre for Research and Technology Hellas. The main concept of this technology is the innovative exploitation of waste cooking oil, which is abundant in Greece and other Mediterranean countries. The technology is based on catalytic hydrotreatment, a traditional petroleum process that is widely employed to upgrade petroleum products. The catalytic hydrotreatment of waste cooking oil was explored with the support of the European Program LIFE+, which funded both the research and development activities as well as the demonstration of the technology. A large quantity of waste cooking oil was collected and converted to the new diesel in a sufficient quantity to fuel a garbage truck for a few months, demonstrating the new technology. The new low-carbon technology offers a new diesel of increased sustainability, superior quality, better fuel consumption, and lower emissions. Furthermore, based on conservative estimations of the available waste cooking oil quantities in Greece and due to the high conversion yields of the proposed technology, it is estimated that waste cooking oil can satisfy approximately 9.5% of the national demand in diesel fuel. Due to all the aforementioned advantages, this technology was granted the second innovation award in the ‘Greece Innovates’ competition organized by Eurobank EFG and Hellenic Federation of Enterprises in July 2011. Towards the exploitation of this technology, the incorporation of waste cooking oil to an existing refining process is explored with the support of the European Commission and the Greek government via the project SustainDiesel. This joint project with the Hellenic Petroleum Group exhibits strong potential for getting scaled-up to industrial scale, thus promoting a green technology into the energy sector.
    01/2013; 2(1). DOI:10.1186/2192-5372-2-9
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