Process for the production of methyle or ethyle esters from fatty acids and glycerine by transesterification of oils or greases

TLDR: In this paper, a mixture of methanol or ethanol and an alkaline catalyst is used for the separation of a light, ester-rich phase and a heavy, glycerine-rich one.

Abstract: Oils or fats, in particular of vegetable, but also of animal origin, are reacted with methanol or ethanol and an alkaline catalyst in the liquid phase. Glycerine and methyl esters of fatty acids or ethyl esters of fatty acids are formed. The reaction is carried out using at least two reaction steps, each reaction step having a mixing reactor and a separator for the separation of a light, ester-rich phase and a heavy, glycerine-rich phase. The oil or the fat, the alcohol and the catalyst are added to the mixing reactor in the first reaction step and these substances are intensively mixed. The alcohol and the catalyst as well as the light, ester-rich phase obtained in the preceding reaction step are added for intensive mixing to the mixing reactor in the second and each further reaction step. A heavy phase is separated in the separator in the second to last reaction step and at least partly fed back to the mixing reactor in the first reaction step. Methyl esters of fatty acids or ethyl esters of fatty acids are obtained from the light, ester-rich phase separated in the last reaction step by at least one further separation treatment. The process is preferably carried out using two reaction steps.