Effect of Factor Interaction in Esterification of High FFA Oil

An efficient methyl ester production process from high free fatty acid(FFA) waste cooking oils (WCO) was explored via  esterification of free fatty acids, an alternative to mineral acids and other common catalysts was tested, Response surface methodology (RSM) based on factorial design was employed to study the effect of independent factor interaction on the process to simultaneously optimize the responses of the reaction (free fatty acid conversion). A quadratic-plynomial mathematical model for the reaction of waste cooking oil (WCO) was developed in terms of catalyst concentration, methanol to oil ratio and reaction time. Analysis of the waste cooking oil indicates that the free fatty acid (FFA) of the oil was 71.4%   having composition of   42.5%, 0.86% and 27.71% of  palmitic, myristic and stearic acids, respectively. %FFA Conversion determined the extent of esterification. The experimental results showed linear coefficient of catalyst load was the most significant model term affecting FFA reduction at 95% confidence level. coefficient of determination (R₂= 0.9511) and F-value= 14.58 proved the model equation to be significant.