Esterifying free fatty acid, useful to prepare bio-diesel, comprises providing a fatty substance comprising free fatty acid, adding alcohol and methane sulfonic acid, conducting esterification reaction, and recovering the fatty substance

摘要

Esterification of free fatty acid contained in a fatty substance, comprises (a) providing a fatty substance comprising 1-100 wt.% of fatty acid; (b) adding at least one alcohol and methane sulfonic acid; (c) conducting the esterification reaction at a temperature of 45-70[deg] C at a pressure of 1-5 atmospheres, preferably 1-2 atmospheres; (d) recovering the fatty substance containing less than 0.5 wt.% of free fatty acids, after separation of the esterification of alcohol and water. An independent claim is included for a process for preparing bio-diesel, comprising: providing fatty substance comprising 1-100 wt.% of free fatty acids; adding alcohol and methane sulfonic acid; conducting esterification at 45-70[deg] C, at a pressure of 1-5 atmospheres, preferably 1-2 atmosphere; recovering the fatty substance comprising 0.5 wt.% of free fatty acids, after separating esterification alcohol and water; optionally filtering the product; adding basic catalyst and alcohol; conducting transesterification at 30-300[deg] C, at a pressure of 1-100 bars; and recovering, optional drying and filtrating of transesterified free fatty acid ester.