PROCESS FOR PRODUCING LOWER ALKYL ESTER OF FATTY ACID

摘要

A process for producing lower-alkyl esters of fatty acids which comprises: an esterification step (A) in which fatty acids contained in a raw material comprising an animal/vegetable fat are esterified with a lower alkyl alcohol using a cation-exchange resin to obtain a reaction mixture containing an ester mixture oil having an acid value of 2 or lower; a transesterification step (B) comprising at least a first-stage step in which the fat contained in the ester mixture oil is transesterified with a lower alkyl alcohol while regulating the amount of an alkali catalyst so as to be in the range of 0.1-1 part by mass per 100 parts by mass of the ester mixture oil according to the acid value; a distillation step (C) in which a liquid distillate containing fatty acid lower-alkyl esters having carbon atoms in smaller numbers is distilled off from the oil phase obtained in the transesterification step (B) to obtain a residue comprising fatty acid lower-alkyl esters having carbon atoms in larger numbers; and a fractionation step (D) comprising at least a step in which the fatty acid lower-alkyl esters having carbon atoms in larger numbers and contained in the residue are separated by distillation into fractions differing in the number of carbon atoms.