Effectiveness of empty fruit bunch ash as the catalyst for palm oil transesterification

Abstract

Empty Fruit Bunch (EFB) resulted from oil palm plantations and mills can be converted into ash through open combustion. The EFB ash then treated by simple calcination and used as a heterogeneous catalyst for biodiesel production. The characteristics of EFB ash were identified based on its elemental composition, porous structure, and active site size. The effectivity of the EFB ash as a catalyst was tested in a transesterification reaction of Refined Bleached Deodorized Palm Oil (RBDPO) with excess methanol (30 %-w) in various catalyst loads (in%-wt). The lab-scale experiments were conducted in a three-neck glass reactor, which was put on the hot plate stirrer at 450 rpm. The EFB ash performed the best as a catalyst by attaining optimal conversion at 65 °C for 1 h with a 16 %-wt of catalyst load. In this condition, most of the standard quality of biodiesel were complied with total glycerol under 0.24% and ester methyl contents up to 98.9 %. The characteristics tests showed that the properties and active side of the EFB ash are excellent after calcination at 600 for 5 h. The recyclability test of EFB ash as a catalyst showed high performance in two repetition cycles, each showing an increase in the yield of biodiesel, which was 92.21 % in cycle 2 and 91.23 % in cycle 3.