Pretreatment and Bentonite-based Catalyzed Conversion of Palm-rubber Seed Oil Blends to Biodiesel

Pretreatment of pre-blended palm and rubber seed oil (50:50) was studied. A parametric study to determine the effect of alcohol-to-oil ratio, catalyst loading and reaction temperature on free fatty acid (FFA) content was also conducted. Interestingly, the FFA percentage of pre-blended feedstock has been reduced significantly from 20% to below 2%. The optimum value for the reduction of FFA was found to be 1.5 wt. % catalyst, alcohol-to- oil ratio 6:1, 62 °C reaction temperature at constant stirring speed (400 rpm) and reaction time 1.5 hours. NaOH/bentonite was also investigated and characterized as a solid heterogeneous catalyst for transesterification. The characterization was conducted by FTIR and XRD analysis. The catalyst showed good results by producing 92 wt% fatty acid methyl esters at reaction temperature of 62 °C and reaction time of 3 hours.