关键词: 游离脂肪酸 , 麻疯树籽油 , 生物柴油 , 酯交换 , 酸催化

Abstract: Biodiesel produced from crude Jatropha curcas L. oil with trace sulfuric acid catalyst (0.02 - 0.08 wt% oil) was investigated at 135 oC -184 oC. Both esterification and transesterification can be well carried out simultaneously. 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: 165 oC, 0.06 wt% H2SO4 of the oil weight, 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 content below 1.0 wt% did not show a noticeable effect on transesterification. Reaction kinetics in the range of 155 oC to 175 oC was also measured.

Key words: free fatty acids, Jatropha curcas L. oil, biodiesel, transesterification, acid catalyst