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Biodiesel Production (biodiesel + production)
Selected AbstractsEvaluation of Glycerol from Biodiesel Production as a Feed Ingredient for Channel Catfish, Ictalurus punctatusJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2010Menghe H. Li Glycerol is the main by-product of biodiesel production from vegetable oils and animal fats. It has been evaluated as an energy source for several farm animals. A study was conducted to examine the effects of various levels of glycerol in channel catfish, Ictalurus punctatus, diets. Fish with mean initial weight of 6.8 ± 0.1 g were stocked in 110-L flow-through aquaria and fed practical diets containing 0, 5, 10, 15, and 20% glycerol for 9 wk. There were no significant differences in feed consumption, weight gain, feed efficiency ratio, and liver lipid level among fish fed diets containing 0, 5, and 10% glycerol. However, fish fed diets containing 15 and 20% glycerol had reduced weight gain, feed efficiency, and liver lipid content. Survival was not affected by dietary glycerol levels. Blood glucose level was significantly higher in fish fed 5% glycerol than fish fed other diets. Fillet protein and fat generally decreased and fillet moisture increased as dietary glycerol level increased. It appears that channel catfish can utilize about 10% glycerol in the diet without adverse effects on feed consumption, weight gain, feed efficiency ratio, hemoglobin, hepatosomatic index, and liver lipid. [source] Mechanism Exploration during Lipase-Mediated Methanolysis of Renewable Oils for Biodiesel Production in a tert -Butanol SystemBIOTECHNOLOGY PROGRESS, Issue 5 2007Wei Du tert -Butanol has been developed as a novel reaction medium for lipase-mediated methanolysis of renewable oils for biodiesel production, in which lipase could maintain high catalytic activity, although the logP value of tert -butanol was just about 0.35. The related mechanism exploration has been carried out, and it has been proposed first in this manuscript that in the biodiesel production system, log Penvironment (log Penvironment = xmethanol log Pmethanol + xoils log Poils + xsolvent log Psolvent) including reactants and organic solvent should be taken into account to consider the effect of the whole environment on lipase activity instead of just considering the effect of the organic solvent itself. Further study showed that the operational stability of the lipase could be improved significantly in this system and there was no loss in lipase activity even after its being continuously used for 200 batches. The phase diagrams of the ternary-components tert -butanol/methanol/rapeseed oils were plotted further, and it was found that the methanol tolerance was the saturated methanol concentration in the system. It was demonstrated first here that the improved stability of the lipase was due to the elimination of negative effects caused by methanol and byproduct glycerol in the tert -butanol system. [source] Biodiesel production by direct methanolysis of oleaginous microbial biomassJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 8 2007Bo Liu Abstract Biodiesel is a renewable fuel conventionally prepared by transesterification of pre-extracted vegetable oils and animal fats of all resources with methanol, catalyzed by strong acids or bases. This paper reports on a novel biodiesel production method that features acid-promoted direct methanolysis of cellular biomass of oleaginous yeasts and filamentous fungi. The process was optimized for tuning operation parameters, such as methanol dosage, catalyst concentration, reaction temperature and time. Up to 98% yield was reached with reaction conditions of 70 °C, under ambient pressure for 20 h and a dried biomass to methanol ratio 1:20 (w/v) catalyzed by either 0.2 mol L,1 H2SO4 or 0.4 mol L,1 HCl. Cetane numbers for these products were estimated to range from 56 to 59. This integrated method is thus effective and technically attractive, as dried microbial biomass as feedstocks omits otherwise tedious and time-consuming oil extraction processes. Copyright © 2007 Society of Chemical Industry [source] Biodiesel fuel production via transesterification of oils using lipase biocatalystGCB BIOENERGY, Issue 2 2009MAN XIAO Abstract Biodiesel has gained widespread importance in recent years as an alternative, renewable liquid transportation fuel. It is derived from natural triglycerides in the presence of an alcohol and an alkali catalyst via a transesterification reaction. To date, transesterification based on the use of chemical catalysts has been predominant for biodiesel production at the industrial scale due to its high conversion efficiency at reasonable cost. Recently, biocatalytic transesterification has received considerable attention due to its favorable conversion rate and relatively simple downstream processing demands for the recovery of by-products and purification of biodiesel. Biocatalysis of the transesterification reaction using commercially purified lipase represents a major cost constraint. However, more cost-effective techniques based on the immobilization of both extracellular and intracellular lipases on support materials facilitate the reusability of the catalyst. Other variables, including the presence of alcohol, glycerol and the activity of water can profoundly affect lipase activity and stability during the reaction. This review evaluates the current status for lipase biocatalyst-mediated production of biodiesel, and identifies the key parameters affecting lipase activity and stability. Pioneer studies on reactor-based lipase conversion of triglycerides are presented. [source] Pan-European regional-scale modelling of water and N efficiencies of rapeseed cultivation for biodiesel productionGLOBAL CHANGE BIOLOGY, Issue 1 2009MARIJN VAN DER VELDE Abstract The energy produced from the investment in biofuel crops needs to account for the environmental impacts on soil, water, climate change and ecosystem services. A regionalized approach is needed to evaluate the environmental costs of large-scale biofuel production. We present a regional pan-European simulation of rapeseed (Brassica napus) cultivation. Rapeseed is the European Union's dominant biofuel crop with a share of about 80% of the feedstock. To improve the assessment of the environmental impact of this biodiesel production, we performed a pan-European simulation of rapeseed cultivation at a 10 × 10 km scale with Environmental Policy Integrated Climate (EPIC). The model runs with a daily time step and model input consists of spatialized meteorological measurements, and topographic, soil, land use, and farm management practices data and information. Default EPIC model parameters were calibrated based on literature. Modelled rapeseed yields were satisfactory compared with yields at regional level reported for 151 regions obtained for the period from 1995 to 2003 for 27 European Union member countries, along with consistent modelled and reported yield responses to precipitation, radiation and vapour pressure deficit at regional level. The model is currently set up so that plant nutrient stress is not occurring. Total fertilizer consumption at country level was compared with IFA/FAO data. This approach allows us to evaluate environmental pressures and efficiencies arising from and associated with rapeseed cultivation to further complete the environmental balance of biofuel production and consumption. [source] One-Pot Homogeneous and Heterogeneous Oxidation of Glycerol to Ketomalonic Acid Mediated by TEMPOADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2003Rosaria Ciriminna Abstract Glycerol, an increasingly abundant by-product of biodiesel production, is selectively converted to ketomalonic acid in one pot at pH 10 using NaOCl as regenerating oxidant in water at 2,°C in the presence of catalytic Br, along with the radical TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl). The reaction can also be conducted at completion over a sol-gel silica glass doped with the nitroxyl radical. Considering the stability and versatility of such doped glasses, these materials show real promise as reusable metal-free catalysts for the conversion of a readily available and renewable biofeedstock into a highly valued compound. [source] Strain isolation and optimization of process parameters for bioconversion of glycerol to lactic acidJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 10 2009An-An Hong Abstract BACKGROUND: The crude glycerol from biodiesel production represents an abundant and inexpensive source which can be used as raw material for lactic acid production. The first aim of this investigation was to select a strain suitable for producing lactic acid from glycerol with a high concentration and productivity. The second aim was to obtain the optimum fermentation conditions, as a basis for large-scale lactate production in the future. RESULTS: Eight bacterial strains, which could aerobically convert glycerol to lactic acid, were screened from soil samples. One of the strains, AC-521, which synthesized lactic acid with a higher concentration, was identified based on its 16S rDNA sequences and physiological characteristics. These results indicated that this strain was a member of Escherichia coli. The optimal fermentation conditions for Escherichia coli AC-521 were 42 °C, pH 6.5, 0.85 min,1 (KLa). CONCLUSION:Escherichia coli AC-521 suitable for producing lactic acid from glycerol with high concentration and productivity was identified. After 88 h of fed-batch fermentation, both the lactic acid concentration and glycerol consumption reached maximum, giving 85.8 g L,1 of lactic acid with a productivity of 0.97 g L,1 h,1 and a yield of 0.9 mol mol,1 glycerol. Copyright © 2009 Society of Chemical Industry [source] Lipase-mediated methanolysis of soybean oils for biodiesel productionJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 1 2008Xin Chen Abstract BACKGROUND: Biodiesel is increasingly perceived as an important component of solutions to the important current issues of fossil fuel shortages and environmental pollution. Biocatalysis of soybean oils using soluble lipase offers an alternative approach to lipase-catalyzed biodiesel production using immobilized enzyme or whole-cell catalysis. The central composite design (CCD) of response surface methodology (RSM) was used here to evaluate the effects of enzyme concentration, temperature, molar ratio of methanol to oil and stirring rate on the yield of fatty methyl ester. RESULTS: Lipase NS81006 from a genetically modified Aspergillus oryzae was utilized as the catalyst for the transesterification of soybean oil for biodiesel production. The experimental data showed that enzyme concentration, molar ratio of methanol to oil and stirring rate had the most significant impact on the yield of fatty methyl ester; a quadratic polynomial equation was obtained for methyl ester yield by multiple regression analysis. The predicted biodiesel yield was 0.928 (w/w) under the optimal conditions and the subsequent verification experiments with biodiesel yield of 0.936 ± 0.014 (w/w) confirmed the validity of the predicted model. CONCLUSION: RSM and CCD were suitable techniques to optimize the transesterification of soybean oil for biodiesel production by soluble lipase NS81006. The related lipase NS81006 reuse stability, chemical or genetic modification, and transesterification mechanism should be taken into consideration. Copyright © 2007 Society of Chemical Industry [source] Transesterification for biodiesel production catalyzed by combined lipases: Optimization and kineticsAICHE JOURNAL, Issue 6 2010Yun Liu Abstract Preparation of biodiesel from waste cooking oil catalyzed by combined lipases in tert -butanol medium was investigated. Several crucial parameters affecting biodiesel yield were optimized by response surface methodology, such as dosage of combined lipases of Novozym 435 and Lipozyme TLIM, weight ratio of Novozym 435 to Lipozyme TLIM, amount of tert -butanol, reaction temperature, and molar ratio of oil to methanol. Under the optimized conditions, the highest biodiesel yield was up to 83.5% The proposed model on biodiesel yield had a satisfactory coefficient of R2 (= 94.02%), and was experimentally verified. The combined lipases exhibited high-operational stability. After 30 cycles (300 h) successively, the activity of combined lipases maintained 85% of its original activity. A reaction kinetic model was proposed to describe the system and deduced to be a pseudo-first-order reaction, and the calculated activation energy was 51.71 kJ/mol. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Two-phase flow behavior in microtube reactors during biodiesel production from waste cooking oilAICHE JOURNAL, Issue 5 2010Guoqing Guan Abstract Flow patterns in the course of transesterification of waste cooking oil (WCO), sunflower oil (SFO) with water and/or oleic acid as a model of WCO, and pure SFO in the presence of a KOH catalyst in microtubes were investigated. FAME yield for the transesterification of WCO reached more than 89% in the microtube reactors with a residence time of 252 s at 333 K. The flow patterns when using WCO were changed from a liquid,liquid slug flow at the inlet region to a parallel flow at the middle region, and then to a homogeneous liquid flow at the outlet region as the reaction proceeded at 333 K. Fine droplets containing glycerol and methanol generally formed in oil slugs when using pure SFO, but were almost unobservable when using WCO. The soap produced from free fatty acids was considered to be the main factor affecting the flow patterns of WCO and SFO. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] A heterogeneous acid-catalyzed process for biodiesel production from enzyme hydrolyzed fatty acidsAICHE JOURNAL, Issue 1 2008Chia-Hung Su Abstract In this work, biodiesel synthesis via fatty acids esterification with methanol is conducted by using a heterogeneous catalyst made from cation-exchange resin. The kinetics of esterification is studied at the different levels of catalyst loading (3.65,53.6%, w/w), reaction temperature (333,353 K) and molar ratio of methanol to fatty acids (1:1 to 20:1). The reaction rate and fatty acids conversion increased with increases in catalyst loading, reaction temperature and molar ratio of feeding reactants. A pseudo-homogeneous kinetic model coupling the effect of catalyst loading, reaction temperature and methanol/fatty acids molar ratio used for describing the process gave a correlation coefficient of 0.95 between experimental and predicted data. The proposed model was further used to predict the optimal operating condition for obtaining equilibrium conversion of 0.99. A reaction temperature of 372.15 K, molar ratio of feeding reactants of 14.9:1 and reaction time of 9.5 h was numerically calculated as the optimal operating condition. Under this optimal operating condition, an experimental verification was carried out and a satisfactory match was observed between experimental data and model prediction. © 2007 American Institute of Chemical Engineers AIChE J, 2008 [source] Evaluation of Glycerol from Biodiesel Production as a Feed Ingredient for Channel Catfish, Ictalurus punctatusJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2010Menghe H. Li Glycerol is the main by-product of biodiesel production from vegetable oils and animal fats. It has been evaluated as an energy source for several farm animals. A study was conducted to examine the effects of various levels of glycerol in channel catfish, Ictalurus punctatus, diets. Fish with mean initial weight of 6.8 ± 0.1 g were stocked in 110-L flow-through aquaria and fed practical diets containing 0, 5, 10, 15, and 20% glycerol for 9 wk. There were no significant differences in feed consumption, weight gain, feed efficiency ratio, and liver lipid level among fish fed diets containing 0, 5, and 10% glycerol. However, fish fed diets containing 15 and 20% glycerol had reduced weight gain, feed efficiency, and liver lipid content. Survival was not affected by dietary glycerol levels. Blood glucose level was significantly higher in fish fed 5% glycerol than fish fed other diets. Fillet protein and fat generally decreased and fillet moisture increased as dietary glycerol level increased. It appears that channel catfish can utilize about 10% glycerol in the diet without adverse effects on feed consumption, weight gain, feed efficiency ratio, hemoglobin, hepatosomatic index, and liver lipid. [source] Olive husk oil transesterification in a fluidized bed reactor with immobilized lipasesASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 3 2009Emanuele Ricca Abstract In the present work, olive husk oil was continuously transesterified by immobilized lipases in a fluidized bed reactor (FBR). Preliminary fluidization tests were run to find the fluidization flow rate for the system under study. Subsequently, the reactor was operated continuously performing high productivity, as compared to literature data on packed bed reactors (PBR) for biodiesel production and to batch data reported in this work. The system was also run in a recycle configuration aiming at studying the effect of repeated passages of the substrates within the reactor, without changing fluidization conditions (i.e. decreasing the fresh feed flow rate to the system by increasing the recycle flow rate, without changing the flow rate entering the reactor). Tests at different recycle ratios were performed to investigate the effect on the process performance of different dilution degrees within the reactor and fresh flow rates fed to the system and to find optimal operating conditions. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source] Research and Development Trends in BiodieselASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 5-6 2004V. Rudolph Biodiesel, a derivative from plant oils or animal fats, has gained widespread acceptance in recent years as a sustainable alternative fuel to petroleum diesel due to its environmental benefits and renewability. Although there are several different ways in which biodiesel can be used or formulated as a fuel such as direct blending, microemulsions and thermal cracking, the most widespread remains the alkyl esters of fatty acids obtained through transesterification of the oils or fats. In transesterification, triglycerides which are the main chemical in oils or fats are converted into esters through reaction with simple alcohols. The physical and chemical properties of the esters thus obtained are very similar to those of the petroleum diesel. This paper reviews the current technologies available for the transesterifications of vegetable oils and animal fats and identifies that the biggest factor deterring a greater market uptake of biodiesel is its cost. It concludes that, in addition to government policy framework, e.g. to reduce the pump price of biodiesel through fuel tax exemption, further technological development presents significant scope for improvement. At present, there are no suitable and developed transesterification technologies that can handle cheap, low-quality feedstocks including waste animal fats and spent cooking oils. These feedstocks contain high percentages of water and free fatty acids which are extremely detrimental to the yield and reaction rates of the transesterification processes. This paper also suggests some future research and development directions and requirements for more competitive biodiesel production. [source] Production of biodiesel: possibilities and challengesBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 1 2007Sulaiman Al-Zuhair Abstract Biodiesel, defined as monoalkyl fatty acid ester (preferentially methyl and ethyl esters), represents a promising alternative fuel for use in compression-ignition (diesel) engines. Biodiesel fuel comes from renewable sources as it is plant- not petroleum-derived and as such it is biodegradable and less toxic. In addition, relative to conventional diesel, its combustion products have reduced levels of particulates, carbon oxides, sulphur oxides and, under some conditions, nitrogen oxides. Enzymatic production of biodiesel has been proposed to overcome the drawbacks of the conventional chemically catalyzed processes. The main obstacle facing full exploitation of the enzyme, lipase, potential is its cost. Therefore, reuse of lipase is essential from the economic point of view, which can be achieved by using the lipase in immobilized form. In addition, immobilized lipase displays improved stability and activity. Common immobilization techniques include attachment to solid supports and entrapment within the matrix of a polymer. This article presents a comparison between conventional processes and enzymatic processes and different possible feedstocks for biodiesel production. In addition, possible ways to overcome the problems facing the use of lipase are described. © 2007 Society of Chemical Industry and John Wiley & Sons, Ltd [source] An integrated approach to biodiesel productionBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2007Article first published online: 25 SEP 200 No abstract is available for this article. [source] Mechanism Exploration during Lipase-Mediated Methanolysis of Renewable Oils for Biodiesel Production in a tert -Butanol SystemBIOTECHNOLOGY PROGRESS, Issue 5 2007Wei Du tert -Butanol has been developed as a novel reaction medium for lipase-mediated methanolysis of renewable oils for biodiesel production, in which lipase could maintain high catalytic activity, although the logP value of tert -butanol was just about 0.35. The related mechanism exploration has been carried out, and it has been proposed first in this manuscript that in the biodiesel production system, log Penvironment (log Penvironment = xmethanol log Pmethanol + xoils log Poils + xsolvent log Psolvent) including reactants and organic solvent should be taken into account to consider the effect of the whole environment on lipase activity instead of just considering the effect of the organic solvent itself. Further study showed that the operational stability of the lipase could be improved significantly in this system and there was no loss in lipase activity even after its being continuously used for 200 batches. The phase diagrams of the ternary-components tert -butanol/methanol/rapeseed oils were plotted further, and it was found that the methanol tolerance was the saturated methanol concentration in the system. It was demonstrated first here that the improved stability of the lipase was due to the elimination of negative effects caused by methanol and byproduct glycerol in the tert -butanol system. [source] Renewable H2 from Glycerol Steam Reforming: Effect of La2O3 and CeO2 Addition to Pt/Al2O3 catalysts.CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 5 2010Tiziano Montini Dr. Abstract Glycerol is the main byproduct of biodiesel production and its increased production volume derives from the increasing demand for biofuels. The conversion of glycerol to hydrogen-rich mixtures presents an attractive route towards sustainable biodiesel production. Here we explored the use of Pt/Al2O3 -based catalysts for the catalytic steam reforming of glycerol, evidencing the influence of La2O3 and CeO2 doping on the catalyst activity and selectivity. The addition of the latter metal oxides to a Pt/Al2O3 catalyst is found to significantly improve the glycerol steam reforming, with high H2 and CO2 selectivities. A good catalytic stability is achieved for the Pt/La2O3/Al2O3 system working at 350,°C, while the Pt/CeO2/Al2O3 catalyst sharply deactivates after 20,h under similar conditions. Studies carried out on fresh and exhausted catalysts reveal that both systems maintain high surface areas and high Pt dispersions. Therefore, the observed catalyst deactivation can be attributed to coke deposition on the active sites throughout the catalytic process and only marginally to Pt nanoparticle sintering. This work suggests that an appropriate support composition is mandatory for preparing high-performance Pt-based catalysts for the sustainable conversion of glycerol into syngas. [source] | |||||||||||||||||||||||||