INVESTIGATION OF THE REFINING STEP OF BIODIESEL PRODUCTION

The ester product of the vegetable oil-alcohol transesterification rea ction (biodiesel) is the best and the most popular diesel fuel alterna tive. The refining of the transesterification reaction products is tec hnically difficult and brings an extra cost. Also, the purity level of the biodiesel must conform to European Union standards for alternativ e diesel fuels. The target of this study was to investigate the refini ng of the product mixture obtained by the transesterification reaction (with an alkali catalyst) of neutralized rapeseed oil (extracted from the seeds of the rape plant cultivated in the Thrace region of Turkey ) with methanol. To obtain pure biodiesel conformable to the standards , methods of washing with hot distilled water, dissolving in petroleum ether and then washing with distilled water, and neutralization with H2SO4 (1:1) were tested in the refining step. Washing with hot distill ed water at 50 degrees C was chosen as the best refining process. The purity of the biodiesel obtained was about 99%.