Basically biodiesel is produced by transesterification of vegetable oils and fats. These raw materials are foods and therefore under discussion. An optional use for this purpose is used cooking oil (UCO). However, this resource is very limited. An additional alternative to used cooking oils are free fatty acids (FAA’s) which is a by-product of the food production. But it is not possible to treat it by known transesterification technologies. In order to be able to process these materials EBNER developed plants for the esterification of these FFA’s to bio oil. This bio oil can be processed in existing transesterification plants as an alternative raw material to produce biodiesel.
In principle there are two processes:
Pressure esterification and cold esterification.