Biodiesel produced from crude Jatropha curcas L.oil with trace sulfuric acid catalyst(0.02%-0.08% oil) was investigated at 135-184 ℃.Both esterification and transesterification can be well carried out simultane-ously...Biodiesel produced from crude Jatropha curcas L.oil with trace sulfuric acid catalyst(0.02%-0.08% oil) was investigated at 135-184 ℃.Both esterification and transesterification can be well carried out simultane-ously.Factors affecting the process were investigated,which included the reaction temperature,reaction time,the molar ratio of alcohol to oil,catalyst amount,water content,free fatty acid(FFA) and fatty acid methyl ester(FAME) content.Under the conditions at 165 ℃,0.06%(by mass) H2SO4 of the oil mass,1.6 MPa and 20:1 methanol/oil ratio,the yield of glycerol reached 84.8% in 2 hours.FFA and FAME showed positive effect on the transesterification in certain extent.The water mass content below 1.0% did not show a noticeable effect on trans-esterification.Reaction kinetics in the range of 155 ℃ to 175 ℃ was also measured.展开更多
Biodiesel, which is a renewable and environmentally friendly fuel, has been studied widely to help remedy increasing environmental problems. One of the key processes of biodiesel production is oil extraction from oils...Biodiesel, which is a renewable and environmentally friendly fuel, has been studied widely to help remedy increasing environmental problems. One of the key processes of biodiesel production is oil extraction from oilseed materials. Switchable solvents can reversibly change from molecular to ionic solvents under atmospheric CO_2,and can be used for oil extraction. N, N-dimethylcyclohexylamine(DMCHA), a switchable solvent, was used to extract oil from Jatropha curcas L. oil seeds to produce biodiesel. The appropriate extraction conditions were:1:2 ratio of seed mass to DMCHA volume, 0.3–1 mm particle size, 200 r·min-1agitation speed, 60 min extraction time, and 30 °C extraction temperature. The extraction ratio was about 83%. This solvent extracted the oil more efficiently than hexane, and is much less volatile. By bubbling CO_2 under 1 atm and 25 °C for 5 h, the oil was separated, and DMCHA was recovered after releasing CO_2 by bubbling N_2 under 1 atm and 60 °C for 2 h. The residual solvent content in oil was about 1.7%. Selectivity of DMCHA was evaluated by detecting the protein and sugar content in oil. Using the oil with residual solvent to conduct transesterification process, the oil conversion ratio was approximately 99.5%.展开更多
Biodiesel （fatty acid methyl ester） has been identified as a non-toxic biodegradable alternative fuel that is obtained from renewable sources. Over the last decade, there has been increasing interest in producing bi...Biodiesel （fatty acid methyl ester） has been identified as a non-toxic biodegradable alternative fuel that is obtained from renewable sources. Over the last decade, there has been increasing interest in producing biodiesel from conventional sources such as soybean, canola, sunflower, and coconut oils. Current efforts are directed towards the development of new non-edible resources. Among these Jatropha Curcas comes at the forefront. In Egypt, Jatropha Curcas has grown successfully using primary treated wastewater. Also, extensive R＆D efforts identified the optimum conditions for the various processing stages namely crushing, extraction, transesterification and purification. Based on the research findings, the techno-economic appraisal of biodiesel production from Jatropha Curcas is conducted. Two nominal capacities namely 8,000 and 50,000 metric tons/yr have been proposed. Several scenarios have been formulated to take into consideration varying productivity （3.4 to 5.8 ton fruits per 4,000 m^2 （acre）） and varying recovery rates of oil from seeds. Economic indicators including capital and production costs for the various processing stages and revenues according to current prices of oil and cake have been obtained. The price of biodiesel that provides a simple rate of return （SRR） on investments of 10% was in the range of $0.3-0.7/liter for the different assumed scenarios which is lower than the prevailing price of biodiesel （about $1/liter） in the US. Thus, in view of experimental results and economic assumptions, there are positive prospects for the production of biodiesel from Jatropha Curcas under Egyptian conditions.展开更多
基金Supported by the Key Grant Project of Chinese Ministry of Education (307023)the National Natural Science Foundation of China (20976108)the National Key Technology Research and Development Program (2007BAD50D05)
文摘Biodiesel produced from crude Jatropha curcas L.oil with trace sulfuric acid catalyst(0.02%-0.08% oil) was investigated at 135-184 ℃.Both esterification and transesterification can be well carried out simultane-ously.Factors affecting the process were investigated,which included the reaction temperature,reaction time,the molar ratio of alcohol to oil,catalyst amount,water content,free fatty acid(FFA) and fatty acid methyl ester(FAME) content.Under the conditions at 165 ℃,0.06%(by mass) H2SO4 of the oil mass,1.6 MPa and 20:1 methanol/oil ratio,the yield of glycerol reached 84.8% in 2 hours.FFA and FAME showed positive effect on the transesterification in certain extent.The water mass content below 1.0% did not show a noticeable effect on trans-esterification.Reaction kinetics in the range of 155 ℃ to 175 ℃ was also measured.
基金Supported by Doctoral Fund of Ministry of Education of China(20130181130006)the National Natural Science Foundation of China(No.21476150)
文摘Biodiesel, which is a renewable and environmentally friendly fuel, has been studied widely to help remedy increasing environmental problems. One of the key processes of biodiesel production is oil extraction from oilseed materials. Switchable solvents can reversibly change from molecular to ionic solvents under atmospheric CO_2,and can be used for oil extraction. N, N-dimethylcyclohexylamine(DMCHA), a switchable solvent, was used to extract oil from Jatropha curcas L. oil seeds to produce biodiesel. The appropriate extraction conditions were:1:2 ratio of seed mass to DMCHA volume, 0.3–1 mm particle size, 200 r·min-1agitation speed, 60 min extraction time, and 30 °C extraction temperature. The extraction ratio was about 83%. This solvent extracted the oil more efficiently than hexane, and is much less volatile. By bubbling CO_2 under 1 atm and 25 °C for 5 h, the oil was separated, and DMCHA was recovered after releasing CO_2 by bubbling N_2 under 1 atm and 60 °C for 2 h. The residual solvent content in oil was about 1.7%. Selectivity of DMCHA was evaluated by detecting the protein and sugar content in oil. Using the oil with residual solvent to conduct transesterification process, the oil conversion ratio was approximately 99.5%.
文摘Biodiesel （fatty acid methyl ester） has been identified as a non-toxic biodegradable alternative fuel that is obtained from renewable sources. Over the last decade, there has been increasing interest in producing biodiesel from conventional sources such as soybean, canola, sunflower, and coconut oils. Current efforts are directed towards the development of new non-edible resources. Among these Jatropha Curcas comes at the forefront. In Egypt, Jatropha Curcas has grown successfully using primary treated wastewater. Also, extensive R＆D efforts identified the optimum conditions for the various processing stages namely crushing, extraction, transesterification and purification. Based on the research findings, the techno-economic appraisal of biodiesel production from Jatropha Curcas is conducted. Two nominal capacities namely 8,000 and 50,000 metric tons/yr have been proposed. Several scenarios have been formulated to take into consideration varying productivity （3.4 to 5.8 ton fruits per 4,000 m^2 （acre）） and varying recovery rates of oil from seeds. Economic indicators including capital and production costs for the various processing stages and revenues according to current prices of oil and cake have been obtained. The price of biodiesel that provides a simple rate of return （SRR） on investments of 10% was in the range of $0.3-0.7/liter for the different assumed scenarios which is lower than the prevailing price of biodiesel （about $1/liter） in the US. Thus, in view of experimental results and economic assumptions, there are positive prospects for the production of biodiesel from Jatropha Curcas under Egyptian conditions.
