Abstract: Soybean oil, methanol and branched-chain alcohol were used to produce biodiesel which contains branched-chain esters.The branched-chain alcohol used is one of these alcohols: isopropanol,isobutyl alcohol, sec-butyl alcohol. Isopropanol has the best reaction property among these alcohols.The effects of reaction time,temperature, catalyst dosage,isopropanol and methanol molar ratio on content of isopropyl esters(IPE) were researched.The GC content of IPE could be more than 50% in this experiments. However, when IPE content was over 20%, separation of glycerin from esters was difficult. The properties of the product with different IPE content were mensurated and its viscosity was higer than fatty acid methyl esters, while condensation point(CP) and cold filter plugging point (CFPP) were decreased from 5 to 8℃ compared with FME.

Key words: biodiesel, branched-chain alcohol, viscosity, pour point, cold filter plugging point