Process for preparing biodiesel with lipase and dehydration in a separate line

摘要

Process for preparing biodiesel from oil and renewable grease catalyzed by lipase with in-line dehydration, where a short chain alcohol selected from the group consisting of methanol, ethanol, propanol and butanol is used as an acyl acceptor, and a lipase It is used as a catalyst to catalyze the transesterification reaction of oil and fat raw material with said short-chain alcohol, to synthesize biodiesel in this way; characterized by the fact that the process comprises the phases of: a. Add oil and fat to a single or multiphase reactor; b. Add 4-8 moles of short-chain alcohol per mole of oil and fat and 20-2000 active units of lipase per gram of oil and fat; c. Perform in-line dehydration with a membrane or molecular sieve separate from the reactor from step a. during the entire process or part of the reaction process; and c. keep the temperature at 20-50 ° C; After 3-10 hours reaction, the yield for the conversion of oil and fat raw material into biodiesel is more than 98%, and the acid number of the final biodiesel product is less than 0.5mg of potassium hydroxide per KOH.