Sanli et al. [7] experimented with different catalysts and
observed that performance of KOH in comparison to NaOH is
better for sooner conversion and optimum amount of catalyst in
1.0% by weight. Using more catalyst than optimum value did not
have any notable impact on yield or properties of biodiesel. When
NaOH is utilised as a catalyst, amount must be taken care of,
because excessive amount will result in formation of gel. Other
alcohols apart from methanol should be used with an acid catalyst
in spite of their reaction rates being too low. Sánchez et al. [57]
kept catalyst concentration in range of 0.6–1.2 wt%. For best yield
of biodiesel, optimum value of catalyst is 1.2 wt%. A higher concentration in the catalyst resulted in reducing the fatty acid butyl
ester conversion due to secondary reactions