Variables affecting the yields of methyl esters derived from in situ esterification of rice bran oil

The influence of specific factors on in situ methanolic esterification of rice bran oil (RBO) using sulfuric acid catalyst was investigated. Using high-FFA rice bran was found to be the most effective means to increase methyl ester yields. The ester content of the extract increased about 67% when the FFA content of oil was increased from 16.6 to 84.5%. Increasing the reaction time beyond 30 min did not affect yields. Increasing the temperature from 20 to 65degreesC elevated the FAME yield by about 30%, but increasing the amount of acid catalyst above 5 mL did not enhance yield, and increasing the methanol dose from 200 to 250 mL had a negligible effect.