Abstract: The invention relates to a low-sulfur diesel fuel containing a maximum amount of 0.2% by weight of sulfur and fatty acid monoalkyl esters in an amount of between 10 and 50,000 ppm as lubricity improvers, with the fatty acid moieties of the fatty acid monoalkyl esters originating from saturated fatty acids by at least 50%, in particular by at least 70%. It has been shown that said fatty acid esters show a substantially better lubricity improvement in a low-sulfur diesel fuel than a biodiesel made of rape oil and soy bean oil.

Abstract: A method for the preparation of fatty acid alkyl esters by transesterification, in particular catalytic transesterification, of a mixture of triglycerides and fatty acids, wherein from a reaction mixture, in which the transesterification is carried out, an ester phase containing fatty acid alkyl esters and a glycerol phase containing fatty acids are formed, which are separated from each other, and the fatty acids are separated from the glycerol phase, whereby a fatty acid phase containing fatty acids is formed, which fatty acids are esterified with an alcohol, which method is characterized in that the fatty acid phase is mixed with a further mixture of triglycerides and fatty acids and the fatty acids contained in the obtained mixture are esterified with an alcohol, whereby an esterification mixture containing triglycerides and fatty acid alkyl esters is obtained, which esterification mixture is transesterified with alcohol so as to form further fatty acid alkyl esters.

Abstract: A method for the preparation of fatty acid alkyl esters by transesterification, in particular catalytic transesterification, of triglycerides, wherein from a reaction mixture, in which the transesterification is carried out, an ester phase and a glycerol phase containing fatty acids, fatty acid salts and/or other fatty acid compounds are formed, which are separated from each other, characterized in that the fatty acids, the fatty acid salts and/or other fatty acid compounds are separated from the glycerol phase, esterified with an alcohol and recycled to a different reaction mixture, in which a further transesterification is carried out. The method according to the invention allows for a transesterification with a high yield of fatty acid esters.