Performance and exhaust emissions of a diesel engine fuelled with Croton megalocarpus (musine) methyl ester

The performance of a 4 stroke 3 cylinder direct injection naturally aspirated, Perkins D3.142 engine was measured in order to determine the suitability of a biofuel produced from the seeds of Croton megalocarpus for engine use. The raw oil from the seeds was subjected to a transesterfication process and supplied to the engine as a Croton methyl ester (CME) in various blends with diesel fuel. The engine performance (brake thermal efficiency, brake specific fuel consumption and exhaust temperature) were measured and evaluated. A Horiba PG-250 portable analyser was used to measure the CO, HC, CO2, NOx, and O2, concentrations. The tests indicated a lower brake thermal efficiency for CME compared with the pure diesel fuel. The exhaust gas temperature increased with increase in load for all tested fuels. It was found that the performance of the CME was comparable to pure diesel fuel but the biodiesel produced lower smoke and NOx emissions. Emissions of CO were reduced at higher loads with the biofuel. The performance of the engine indicated that CME has properties and characteristics that make it a viable additive or alternative to conventional fossil diesel fuel.