Biodiesel production from Indonesian rice bran by in situ esterification
was carried out in this work with the objective of studying
the effect of methanol to rice bran ratio, sulfuric acid concentration
in methanol, and reaction time on the purity and recovery
of FAMEs. Methanol to rice bran ratio and reaction time were
the important factors in these reaction conditions. However, their
interactions were not significantly different. Rapid conversion of
FFAs into FAMEs was observed within 60 min. After that, the conversion
rate was slower. The FAMEs obtained at 1.5% (v/v) sulfuric
acid in methanol were not significantly higher than those obtained
at 5% (v/v) sulfuric acid in methanol. Moreover, the purity of FAMEs
remains stable with increasing sulfuric acid concentration.