A study on the production of biodiesel from used frying oil

The study was carried out to utilize waste frying oil for biodiesel production because it is cheap,easily available and renewable raw material. the used frying oil was analyzed for water contents (0.43 %),iodine value (52),sponification value (205),free fatty acids (8.7 %) and acid value (0.8 mg koh/g). esterification and transesterification were conducted to convert free fatty acids and triglycerides to methyl ester (biodiesel),respectively. one-step and two-step transeterification reactions were carried out to measure the efficiency of these processes for biodiesel production. the biodiesel produced from used frying oil was examined for flash point (185 °c),kinematic viscosity (4.86 mm2/s) and specific gravity (0.884 g/ml) that were meeting the limits of astm and thai standards. hence,it was proved to be a useful technique for biodiesel production at commercial scale.