The potential of using cocoa pod husks as green solid base catalysts for the transesterification of soybean oil into biodiesel: Effects of biodiesel on engine performance

In this study, the feasibility of using potash from cocoa pod husks (CPHs) in the transesterification of soybean oil into biodiesel was investigated. Both supported (CPH/MgO) and unsupported (CPH ash) catalysts of potash prepared from CPH were used as green heterogeneous catalysts for biodiesel production. Under optimum conditions for the CPH/MgO-catalyzed (oil/methanol ratio of 1:6, 60 °C, 60 min, 1 wt.% of MgO doped CPH ash catalyst) and the CPH-catalyzed (60 °C, oil/methanol ratio of 1:6, 120 min, 1 wt.% of CPH ash) transesterification reactions, biodiesel samples (98.7% and 91.4% yields for CPH/MgO and CPH ash catalysts respectively) with specifications falling within the limits of the European biodiesel quality standard (EN 14112) were obtained. Brake thermal efficiencies and torque were measured for each fuel sample at different loads. Engine test showed a better performance for all the fuel samples (B100 and B40) with B40 showing close characteristics of petroleum diesel. Thus, this first report on the utilization of CPH as catalyst for biodiesel shows a high feasibility of producing green heterogeneous base catalysts commercially from CPH for sustainable biodiesel production.

► A green heterogeneous base catalyst was prepared from cocoa pod husks (CPHs). ► Transesterified soybean oil with CPH potash catalyst gave 91.4% biodiesel yield. ► Transesterified soybean oil with CPH/MgO catalyst gave 98.7% biodiesel yield. ► Engine performance test showed that B40 had close characteristics of petro-diesel.