Showing papers on "Transesterification published in 2009"
TL;DR: A triangular graph based on the composition in monounsaturated, polyunsaturated and saturated methyl esters was built in order to predict the critical parameters of European standard for whatever biodiesel, known its composition.
1,667 citations
TL;DR: In this article, the catalytic activity of several solid base and acid catalysts, particularly metal oxides and supported metal oxide, was reviewed for transesterification and esterification reactions simultaneously and converted oils with high amount of Free Fatty Acids.
767 citations
TL;DR: This review covers the process by which biodiesel is prepared, the types of catalysts that may be used for the production of biodiesel, the influence of free fatty acids on biodiesel production, the use of different monohydric alcohols in the preparation of biod diesel, the effects of blending biodiesel with other fuels on fuel properties, alternative uses for biod Diesel, and value-added uses of glycerol.
Abstract: Biodiesel, defined as the mono-alkyl esters of vegetable oils or animal fats, is an environmentally attractive alternative to conventional petroleum diesel fuel (petrodiesel). Produced by transesterification with a monohydric alcohol, usually methanol, biodiesel has many important technical advantages over petrodiesel, such as inherent lubricity, low toxicity, derivation from a renewable and domestic feedstock, superior flash point and biodegradability, negligible sulfur content, and lower exhaust emissions. Important disadvantages of biodiesel include high feedstock cost, inferior storage and oxidative stability, lower volumetric energy content, inferior low-temperature operability, and in some cases, higher NO
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exhaust emissions. This review covers the process by which biodiesel is prepared, the types of catalysts that may be used for the production of biodiesel, the influence of free fatty acids on biodiesel production, the use of different monohydric alcohols in the preparation of biodiesel, the influence of biodiesel composition on fuel properties, the influence of blending biodiesel with other fuels on fuel properties, alternative uses for biodiesel, and value-added uses of glycerol, a co-product of biodiesel production. A particular emphasis is placed on alternative feedstocks for biodiesel production. Lastly, future challenges and outlook for biodiesel are discussed.
766 citations
TL;DR: This review presents a critical analysis of the current status of research in enzymatic biodiesel production and accentuates the main obstacles to the widespread use of enzymes for commercial biodiesel transesterification.
Abstract: Enzymatic biodiesel production has been investigated intensively, but is presently employed industrially only in a 20,000 tons/year pilot plant in China (Du et al. [2008] Appl Microbiol Technol 79(3):331-337). This review presents a critical analysis of the current status of research in this area and accentuates the main obstacles to the widespread use of enzymes for commercial biodiesel transesterification. Improved results for enzymatic catalysis are seen with respect to increased yield, reaction time and stability, but the performance and price of the enzymes need further advances for them to become attractive industrially for biodiesel production. Critical aspects such as mass transfer limitations, use of solvents and water activity are discussed together with process considerations and evaluation of possible reactor configurations, if industrial production with enzymes is to be carried out. Results of published studies on the productivity of enzymes are also presented and compared to the use of chemical catalysts.
702 citations
TL;DR: In this paper, the authors reviewed various types of heterogeneous solid acids and bases in the production of biodiesel from transesterification of triglycerides and compared the yields and conversion from various catalytic systems.
Abstract: Increasing number of researches focusing on the use of solid heterogeneous catalysts for the production of biodiesel provides evidence that these catalysts continue to evolve as viable alternatives. While liquid alkaline metal alkoxides remain to be appealing in the industries, it is expected that solid base catalyst will soon become more attractive due to the economics and environmental concern. Limited researches have shown that the conversion by solid base catalysts was comparable to that of the existing alkoxide system. This paper reviews various types of heterogeneous solid acids and bases in the production of biodiesel from transesterification of triglycerides. Unconventional enzymatic and non-catalytic supercritical methanol transesterification are also presented. The yields and conversion from various catalytic systems are compared, and the advantages and disadvantages of the systems discussed.
563 citations
TL;DR: Utilization of eggshell as a catalyst for biodiesel production not only provides a cost-effective and environmental friendly way of recycling this solid eggshell waste, significantly reducing its environmental effects, but also reduces the price of biodiesel to make biodiesel competitive with petroleum diesel.
527 citations
TL;DR: In this article, the authors investigated different parameters for the optimization of biodiesel production and suggested the optimum conditions for the production of the mono-alkyl-esters of long chain fatty acids derived from renewable feedstocks, such as vegetable oils or animal fats, for use in compression ignition engines.
507 citations
TL;DR: In this article, a two-step and single-step transesterification process was used to produce biodiesel from high free fatty acid (FFA) non-edible oils and edible vegetable oils, respectively.
475 citations
TL;DR: In this paper, the authors provide a wide overview on the possibility of heterogeneous acid catalysts for biodiesel production replacing the homogeneous conventional process, which is usually prepared from crude and refined triglyceride containing raw materials, such as vegetable oils, animal fats and wastes.
473 citations
TL;DR: This is the first report on biodiesel synthesis using immobilized E. aerogenes lipase, and there was negligible loss in lipase activity even after repeated use for seven cycles.
Abstract: Transesterification of Jatropha oil was carried out in t-butanol solvent using immobilized lipase from Enterobacter aerogenes. The presence of t-butanol significantly reduced the negative effects caused by both methanol and glycerol. The effects of various reaction parameters on transesterification of Jatropha oil were studied. The maximum yield of biodiesel was 94% (of which 68% conversion was achieved with respect to methyl oleate) with an oil:methanol molar ratio of 1:4, 50 U of immobilized lipase/g of oil, and a t-butanol:oil volume ratio of 0.8:1 at 55°C after 48 h of reaction time. There was negligible loss in lipase activity even after repeated use for seven cycles. To the best of our knowledge this is the first report on biodiesel synthesis using immobilized E. aerogenes lipase.
443 citations
TL;DR: In this article, a transesterification reaction by potassium hydroxide (KOH) catalytic and supercritical methanol methods obtaining for biodiesel has been conducted, where free fatty acids in the waste cooking oil are transesterified simultaneously in supercritical meta-hanol method.
TL;DR: In this paper, the interplay between the crucial parameters of the lipase-catalyzed reactions carried out in nonaqueous systems and the yield of biodiesel synthesis is investigated.
TL;DR: In this paper, a single-step method was developed for biodiesel production from unrefined or waste oils using a series of heterogeneous zinc and lanthanum mixed oxides.
Abstract: A single-step method was developed for biodiesel production from unrefined or waste oils using a series of heterogeneous zinc and lanthanum mixed oxides. Effects of metal oxide molar ratio, free fatty acids (FFA) and water content in feedstock, molar ratio of methanol and oil, and reaction temperature on the yield of biodiesel were investigated. A strong interaction between Zn and La species was observed with enhanced catalyst activities. Lanthanum promoted zinc oxide distribution, and increased the surface acid and base sites. The catalyst with 3:1 ratio of zinc to lanthanum was found to simultaneously catalyze the oil transesterification and fatty acid esterification reactions, while minimizing oil and biodiesel hydrolysis. A reaction temperature window of 170–220 °C was found for the biodiesel formation. A high yield (96%) of fatty acid methyl esters (FAME) was obtained within 3 h even using unrefined or waste oils.
TL;DR: In this article, the transesterification of palm oil to methyl esters (biodiesel) was studied using KOH loaded on Al 2 O 3 and NaY zeolite supports as heterogeneous catalysts.
TL;DR: In this article, an attempt has been made on review of biodiesel production, methods of analyzing, bio-diesel standard, resources available, process developed performance in internal combustion engines.
Abstract: Bio-diesel has become more attractive recently because of its environmental benefits and it is derived from renewable resources, bio degradable and non-toxic in nature. Several bio-diesel production methods have been developed, among which transesterification using alkali catalyst gives high level of conversion of triglycerides to their corresponding methyl ester in short reaction time. The process of transesterification is affected by the reaction condition, molar ratio of alcohol to oil, type of alcohol, type and amount of catalysts, reaction time and temperature, purity of reactants free fatty acids and water content of oils or fats. In this work, an attempt has been made on review of bio-diesel production, methods of analyzing, bio-diesel standard, resources available, process developed performance in internal combustion engines, teardown analysis of bio-diesel B20 operated vehicle, recommendation for development of bio-fuels, environmental considerations, economic aspects and advantages. The technical tools and process for monitoring the transesterification reaction like TLC, GC, HPLC, GPC, 1H NMR and NIR have also been summarized in this paper.
TL;DR: This research was aimed at studying the acceleration of the catalytic activity of calcium oxide (CaO) for developing an effective heterogeneous catalyst for biodiesel production by the transesterification of plant oil with methanol.
TL;DR: Results indicate oyster shell waste combusted at high temperature can be reused in biodiesel production as a catalyst and yield was more than 70% with high biodiesel purity.
TL;DR: In this article, various methods of preparation of biodiesel from non-edible filtered Jatropha (Jatropha curcas), Karanja (Pongamia pinnata) and Polanga (Calophyllum inophyllus) oil have been described.
TL;DR: It is found that pure CaO and MgO were not active and CaO/Al(2)O(3) catalyst among all the mixed oxide catalysts showed the highest activity and not only the basic site density but also the basic strength is important to achieve the high biodiesel yield.
TL;DR: This review focuses on new catalytic systems for the transesterification of oils to the corresponding ethyl/methyl esters of fatty acids and some innovative/emerging technologies for the production of biodiesel, such as the catalytic hydrocracking of vegetable oils to hydrocarbons.
Abstract: The predicted shortage of fossil fuels and related environmental concerns have recently attracted significant attention to scientific and technological issues concerning the conversion of biomass into fuels. First-generation biodiesel, obtained from vegetable oils and animal fats by transesterification, relies on commercial technology and rich scientific background, though continuous progress in this field offers opportunities for improvement. This review focuses on new catalytic systems for the transesterification of oils to the corresponding ethyl/methyl esters of fatty acids. It also addresses some innovative/emerging technologies for the production of biodiesel, such as the catalytic hydrocracking of vegetable oils to hydrocarbons. The special role of the catalyst as a key to efficient technology is outlined, together with the other important factors that affect the yield and quality of the product, including feedstock-related properties and various system conditions.
TL;DR: In this article, the synthesis of glycerol carbonate from glycerols and dimethyl carbonate by transesterification is reported, and a reaction optimization study has been carried out with CaO as catalyst by using a factorial design of experiments leading to operation conditions for achieving a 100% conversion and a > 95% yield at 1.5h reaction time.
Abstract: The synthesis of glycerol carbonate from glycerol and dimethyl carbonate by transesterification is reported. Firstly, a catalyst screening has been performed by studying the influence of different basic and acid homogeneous and heterogeneous catalysts on reaction results. Catalytic activity is extremely low for acidic catalysts indicating that reaction rate is very slow. On the contrary, high conversions and yields are obtained for basic catalysts. Catalytic activity increases with catalyst basic strength. The best heterogeneous catalyst is CaO. Calcination of CaO increases dramatically its activity due to calcium hydroxide removal from its surface. A reaction optimization study has been carried out with CaO as catalyst by using a factorial design of experiments leading to operation conditions for achieving a 100% conversion and a >95% yield at 1.5 h reaction time: 95 °C, catalyst/glycerol molar ratio = 0.06 and dimethyl carbonate/glycerol molar ratio = 3.5. Carbonate glycerol can be easily isolated by filtering the catalyst out and evaporating the filtrate at vacuum. Leaching of catalyst in reaction medium was lower than 0.34%. Catalyst recycling leads to a quick decrease in both conversions and yields probably due to a combination of catalyst deactivation by CaO exposure to air between catalytic runs, and a decrease in the catalyst surface area available for reaction due to particle agglomeration.
TL;DR: A two-step process consisting of pre-esterification and transesterification was developed to produce biodiesel from crude Jatropha curcas L. oil and the yield was higher than 98% in 20 min using 1.3% KOH as catalyst and a molar ratio of methanol to oil 6:1 at 64 °C.
TL;DR: Results indicated a significant interactive effect between temperature, acid concentration, and methanol to sludge mass ratio on the FAME yield for the insitu transesterification of primary sludge, while the Fame yield for secondary sludge was significantly affected by the independent effects of the three factors investigated.
TL;DR: In this paper, the authors reported on the successfully production of biodiesel by transesterification of crude rice bran oil (RBO) by three-step process, which included two-steps pretreatment process in the presence of sulfuric acid catalyst.
TL;DR: In this article, the authors introduced the filamentous fungus Mucor circinelloides as a potential feedstock for biodiesel production, which showed a high content (>85%) of saponifiable matter and a suitable fatty acid profile.
TL;DR: In this paper, the authors studied the dependence of the conversion of Jatropha oil on the reaction variables such as the catalyst loading, the molar ratio of methanol to oil, reaction temperature, agitation speed and reaction time.
TL;DR: The results showed very good agreement compatibility between mass transfer model and the experimental results obtained from immobilized lipase packed bed reactor operation, showing that in this case the FAME yield was mass transfer controlled.
TL;DR: In this article, a techno-economic analysis of a process that produces biodiesel from vegetable oils is presented with the aim to investigate the dependence of the critical profitability indicators on the production capacity.
TL;DR: It was shown that immobilized enzymes retain their activities during 10 repeated batch reactions at 25 degrees C, each lasting 24h, which means the developed novel method could have a potential to be used industrially for the production of chemicals requiring immobilized lipases.
TL;DR: In this article, a three-step fixed bed reaction was used to synthesize a mixture of WCO, water, methanol, and solvent (hexane), and the main product was a fatty acid methyl ester (FAME), of which methyl oleate was the main component.