摘要 |
The present invention relates to a method for manufacturing biodiesel (fatty acid methyl and ethyl esters) by acid transesterification of a natural oil, for example, a vegetable oil, with methanol and/or ethanol by means of aliphatic sulphonic acids. The advantage of transesterification by means of sulphonic acid, in particular methane sulphonic acid or perfluorobutane sulphonic acid, is the possible use of vegetable oils having water contents and proportions of free fatty acids. No by-products are formed and saponification is avoided due to the acid transesterification. |