Keeping the oil volume and methanol concentration constant, while varying sulphuric acid concentration, a
combination of 1.25%v/v sulphuric acid to-oil volume and 63ml of methanol in figure(11) gives acid value of
0.81mgKOH/g-oil, while the combination of 0.5%v/v sulphuric acid to- oil volume and 45ml of methanol in
figure(6) gives acid value of 20.74mgKOH/g-oil, representing the lowest and highest acid values in all the
experiments. In figure 9, the acid value shows sharp decrease from 1.72mgKOH/g to 0.86mgKOH/g and start
increasing as the concentration of sulphuric acid is just above 0.75%v/v to-oil volume indicating that > 0.75%,
the sulphuric acid concentration becomes excess and aid in acid value increment. The research shows that the
acid value obtained in figure(6) at a combination of 0.5%v/v sulphuric acid to-oil volume and 45ml of methanol
represent a reduction level of acid value with just 30.57%, while in figure(11) at a combination of 1.25%v/v
sulphuric acid to-oil volume and 63ml of methanol represents reduction level of acid value with 97.29% in one
step process.