Synthesis of polyol fatty acid polyesters using column with inert gas stripping

摘要

This processes for the synthesis of polyol fatty acid polyester by transesterificataion of a polyol and comprises: a) Reacting polyol with a first portion of fatty acid lower alkyl ester to provide a first step reaction product in which substantially all of the polyol is reacted with at least one fatty acid alkyl ester. b) The processes then employ a multistage column providing substantial plug flow of liquid for further transesterification of the first step reaction product. c) Partially esterified polyol, a second portion of fatty acid lower alkyl ester and catalyst are fed to the column to form a mixture and cause further transesterification of the partially esterified polyol and fatty acid alkyl ester, with alkylalcohol being formed as a by-product. d) The resulting liquid mixture of reactants and product is passed in a first direction between adjacent stages through the column for further reaction of partially esterified polyol with fatty acid alkyl ester. e) An inert stripping or sparging gas is fed through the column in a second direction between adjacent stages, counter current to the flow of the liquid mixture between adjacent stages in the first direction, with radial shear agitation. f) Finally the alkyl alcohol by-product of the polyol-fatty acid alkyl ester reaction is transferred from the liquid mixture to the inert gas.