Abstract
Methyl ester from fatty acid of plant oils is called "Biodiesel" and has several advantages as follows; Carbon neutral and renewable energy due to biomass preventing an increase green house effect gas emission; CO2, Safety fuel due to higher flash point. Biodiesel fuel having relatively high cetane number, Low smoke emission due to oxygenated fuel, Ultra low sulfur fuel, Low environment impact due to high biodegradation fuel. The huge biodiversity of Indonesia provides more than two dozen of fatty-oil yielding plants that may be exploited to produce Biodiesel. Palm and Physic Nut (Jatropha Curcas) are the most potential of these. Physic nut seed oil is still practically unexploited commercially, most probably because they are non edible. However, offer the potential to replace/substitute palm oil as Biodiesel raw material during the periods of high food sector demand. In this study, the engine test bed procedure for an DI diesel engine injector nozzle coking test was adapted for neat Biodiesel fuel of Palm Oil and Physic Nuts, and also for blended with diesel oil fuel. In addition exhaust gas emissions such as Nitrogen Oxides (NOx), Carbon Monoxide (CO), and Brake Specific Fuel Consumption (BSFC) before and after the test also measured and compared it.
Keywords: diesel engine, direct injection, biodiesel fuel, palm oil, physic nut (Jatropha Curcas), injector nozzle coking test, exhaust emissions, brake specific fuel consumption.