Biodiesel production from jatropha seeds with bead-type heterogeneous catalyst

Abstract

This study adapted two types of heterogeneous catalysts to the process of manufacturing biodiesel through a two-stage process using Jatropha oil as a raw material. The acid value of Jatropha oil prepared in this study was 11.3 mgKOH/g, and it could be reduced to less than 0.4 mgKOH/g via 2 h of esterification using the Amberlyst-15 catalyst. The pretreated oil was used as a raw material for transesterification in a Carberry spinning catalyst basket reactor equipped with a bead-type dolomite catalyst, as the bead-type dolomite catalyst prepared with 20 wt% pseudoboehmite sol as an inorganic binder was found to be the optimal catalyst for the transesterification reaction. The spent dolomite bead catalyst could be regenerated and reused twice without a loss of activity during transesterification. However, the catalyst when repeatedly regenerated three times nearly lost its active sites, which is attributed to the conversion of CaO to CaCO3 during the regeneration and reuse procedure.