After the reaction completed, the catalyst was removed from
the mixture using centrifugation. The mixture was centrifuged at
5000 rpm for 10 min by centrifuge to separate catalyst, glycerol
and methyl esters phases. The biodiesel was obtained in the upper
layer, while the glycerol as the byproduct was in the lower layer
with the catalyst. The methyl ester, biodiesel was collected and
performed washing purification process by hot distilled water.
Fig. 1 shows the schematic diagram of the process, which includes,
pre-treatment of feedstock, catalyst preparation, esterification and
transesterification reaction, catalyst removal, biodiesel separation
and purification.