The preparation of macauba fruits （Acrocomia aculeate （Jacq.） Lodd. ex Martius） both for oil extraction by continuous pressing and biodiesel production were investigated. The fruits and its pulp and kernel were ch...The preparation of macauba fruits （Acrocomia aculeate （Jacq.） Lodd. ex Martius） both for oil extraction by continuous pressing and biodiesel production were investigated. The fruits and its pulp and kernel were characterized for their resulting oils. Experimental design was carried out to study the transesterification of each oil to obtain the concentrations of ethanol and catalyst that would provide the best biodiesel yield. A higher amount of biodiesel was produced from the best conditions to evaluate some characteristics as specified by ANP （National Agency of Petroleum, Natural Gas and Biofuels）. The results showed a variation in the fruits composition and different characteristics presented by the pulp and kernel oil. It was possible to define technological steps to obtain oil from the fruits of macauba and find the optimal conditions to biodiesel production, concentration of catalyst 4.42% and 5% and 13.3：1 and 9：1 ethanol：oil molar ratio to kernel oil and pulp oil, respectively.展开更多
This article analyzes the standards for car exhaust emissions and gasoline and diesel quality in Europe and the US. As revealed by the evolution of gasoline and diesel standards in China, the gasoline and diesel compo...This article analyzes the standards for car exhaust emissions and gasoline and diesel quality in Europe and the US. As revealed by the evolution of gasoline and diesel standards in China, the gasoline and diesel compositions of China and the exhaust gas emissions standard are closely related with the specifics of the petroleum refining industry and automotive industry in China. After studying the current situations of gasoline and diesel quality in China while taking into account the commonly accepted practice in the overseas this article raises some suggestions on development of gasoline and diesel standards in compliance with the actual conditions of China.展开更多
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
Microalgae lipids/oils are a promising feedstock for biodiesel production. The desired lipids are triacylglycerols. These can either be transesterified to biodiesel or decarboxylated to ＂green diesel＂. Increasing mi...Microalgae lipids/oils are a promising feedstock for biodiesel production. The desired lipids are triacylglycerols. These can either be transesterified to biodiesel or decarboxylated to ＂green diesel＂. Increasing microalgae lipids production by thermal stressing is important in improving the economics of biodiesel production, but its effectiveness needs to be determined. This paper focuses on the effect of cooling stressing lipid triggering on the microalgae production and lipids yield. Two microalgae species were studied, Chlorella sp. and Dunaliella. In each case, microalgae were grown in two identical 2 L PBRs （photobiorectors） at room temperature. At the end of the exponential growth phase, one PBR was placed in a cold environment while the other PBR was left at room temperature. Microalgae was harvested, freeze dried and the algae oil was extracted. Measurements show that cooling stressing slightly increased the biomass of algae （11% for C2 and 13% for Dunaliella）, but it decreased the lipids content of the microalgae, 62% for Chlorella sp. and 13% for Dunaliella. The net effect is a decrease in the lipid production rate （mg lipid/L-day） 58% in case of Chlorella sp., and 2% in case of Dunaliella.展开更多
文摘The preparation of macauba fruits （Acrocomia aculeate （Jacq.） Lodd. ex Martius） both for oil extraction by continuous pressing and biodiesel production were investigated. The fruits and its pulp and kernel were characterized for their resulting oils. Experimental design was carried out to study the transesterification of each oil to obtain the concentrations of ethanol and catalyst that would provide the best biodiesel yield. A higher amount of biodiesel was produced from the best conditions to evaluate some characteristics as specified by ANP （National Agency of Petroleum, Natural Gas and Biofuels）. The results showed a variation in the fruits composition and different characteristics presented by the pulp and kernel oil. It was possible to define technological steps to obtain oil from the fruits of macauba and find the optimal conditions to biodiesel production, concentration of catalyst 4.42% and 5% and 13.3：1 and 9：1 ethanol：oil molar ratio to kernel oil and pulp oil, respectively.
文摘This article analyzes the standards for car exhaust emissions and gasoline and diesel quality in Europe and the US. As revealed by the evolution of gasoline and diesel standards in China, the gasoline and diesel compositions of China and the exhaust gas emissions standard are closely related with the specifics of the petroleum refining industry and automotive industry in China. After studying the current situations of gasoline and diesel quality in China while taking into account the commonly accepted practice in the overseas this article raises some suggestions on development of gasoline and diesel standards in compliance with the actual conditions of China.
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.
文摘Microalgae lipids/oils are a promising feedstock for biodiesel production. The desired lipids are triacylglycerols. These can either be transesterified to biodiesel or decarboxylated to ＂green diesel＂. Increasing microalgae lipids production by thermal stressing is important in improving the economics of biodiesel production, but its effectiveness needs to be determined. This paper focuses on the effect of cooling stressing lipid triggering on the microalgae production and lipids yield. Two microalgae species were studied, Chlorella sp. and Dunaliella. In each case, microalgae were grown in two identical 2 L PBRs （photobiorectors） at room temperature. At the end of the exponential growth phase, one PBR was placed in a cold environment while the other PBR was left at room temperature. Microalgae was harvested, freeze dried and the algae oil was extracted. Measurements show that cooling stressing slightly increased the biomass of algae （11% for C2 and 13% for Dunaliella）, but it decreased the lipids content of the microalgae, 62% for Chlorella sp. and 13% for Dunaliella. The net effect is a decrease in the lipid production rate （mg lipid/L-day） 58% in case of Chlorella sp., and 2% in case of Dunaliella.
