Esterification of High Free Fatty Acid Jatropha curcas Oil for Biodiesel Production

This study investigated the esterification of high free fatty acid (FFA) Jatropha curcas (J. curcas) seed oil (6.3 to14.6 %) to produce biodiesel using sulphuric acid with reaction parameters 1% H2SO4, 600 rpm at 60 oC and one hour reaction time. At methanol to oil ratio 3:1, FFAs were reduced to 4.73% with conversion 45%; at 6:1 methanol to oil ratio, FFAs were reduced to 2.31% with conversion 72%; at 7.5:1 methanol to oil ratio FFAs are decreased to less than 2% with conversion ≥85% and there is no considerable difference when increasing methanol to oil ratio to 9:1. Hence the optimum methanol to oil molar ratio is 7.5:1, moreover, the esterification process is not affected by the initial FFA.