Patent ID: 7652156
Filing Date: 2010-01-26
Classification: C10L,C11C,Y02E

Abstract:
1. A method for manufacturing fatty acid ethyl esters from an oil encompassing vegetable or animal oils or fat or other glyceride mixtures, said oil having an acid number of at most 2, comprising a succession of stages as follows: a batch stage (a) wherein the oil, the fat or the glyceride mixture is catalytically transesterified by ethanol with a soluble basic catalyst or a basic catalyst that becomes soluble during the reaction with ethanol, said ethanol having a water content of between 3000 and 5000 ppm, thereby forming a mixture of fatty acid esters and glycerin, a stage (b) wherein the glycerin formed is decanted from said mixture of fatty acid esters and glycerin and removed without any steps of evaporating excess ethanol or introducing additional water or a hydrocarbon solvent to facilitate decantation and obtain an ester product, a batch stage (c) wherein a second transesterification reaction is carried out on said ester product of stage (b) with makeup ethanol, said makeup ethanol having a water content of between 3000 and 5000 ppm, in the presence of makeup soluble basic catalyst or a basic catalyst that becomes soluble during the reaction so as to obtain a product whose ethyl ester content is at least 97% by mass, a stage (d) wherein controlled neutralization of the soluble basic catalyst in a reaction medium from stage (c) is carried out, said neutralization comprising adding a sufficient content of mineral acid to neutralize said basic catalyst selectively, and to provide an acidified product having an acid number not higher than 0.5, thereby substantially preventing a retroreaction in a following distillation step, a stage (e) wherein excess ethanol is removed from said acidification product of stage (d) by said distillation step, a stage (f) wherein resultant ethyl ester of stage (e) undergoes purification comprising at least one water wash sequence, and a stage (g) wherein resultant washed ethyl ester of stage (f) is dried.