Abstract: The present invention relates to a method for producing fatty acid esters of monovalent alkyl alcohols by base-catalyzed transesterification of fatty acid esters of polyvalent alcohols. In said method, oils are used which contain free fatty acids and phosphatides, in addition to fatty acid esters of polyvalent alcohols. The method consists of several stages. The fatty acids contained in the starting material are treated with a base mixture of glycerine and a catalyst. This mixture is produced as a polar phase in the following transesterification stages and can be separated from the reaction mixture, using phase separation. Calculation procedures are provided for determining the minimum amount of catalyst necessary, depending on the acid number of the oil. The invention also relates to the use of esters produced by this method as diesel fuels.

Abstract: The present invention relates to a method for producing fatty acid esters of monovalent alkyl alcohols by base-catalyzed transesterification of fatty acid esters of polyvalent alcohols. In said method, oils are used which contain free fatty acids and phosphatides, in addition to fatty acid esters of polyvalent alcohols. The method consists of several stages. The fatty acids contained in the starting material are treated with a base mixture of glycerine and a catalyst. This mixture is produced as a polar phase in the following transesterification stages and can be separated from the reaction mixture, using phase separation. Calculation procedures are provided for determining the minimum amount of catalyst necessary, depending on the acid number of the oil. The invention also relates to the use of esters produced by this method as diesel fuels.