METHOD FOR PRODUCING A FATTY ACID ESTER MIXTURE FROM WASTE FATS OR OILS AND USE OF THIS MIXTURE AS A FORCE. FUEL

摘要

The present invention is concerned with the use of various types of used vegetable and/or animal oils and fats in the form of special waste from, for example, domestic sources, the catering trade, slaughterhouses or sewage treatment plants for the production of diesel fuel or heating fuel. For this purpose, these fats and oils are converted by processes of the parent patent No. 386222 by transesterification with alcohols into the corresponding fatty acid esters. After the crude product has been heated appropriately above its melting point, the transesterification takes place with a suitable monohydric alcohol in the presence of a basic transesterification catalyst. After removal of the glycerol phase which contains the free fatty acids and most of the catalyst, and other impurities in the crude product, final residues of catalyst present in solution are removed from the crude ester phase using an acidic cation exchanger. The fatty acid ester mixture obtained in this way can be employed without further purification both as diesel fuel and as heating oil.