Mahua oil (madhuca indica oil) derivatives as a renewable fuel for diesel engine systems in India: A performance and emissions comparative study

In the present investigation methyl and ethyl ester of mahua oil was prepared by trensester-ification, using sulfuric acid (H2SO4) as a catalyst, and tested in a 4-stroke direct injection naturally-aspirated diesel engine. Tests were conducted at a constant speed of 1500 rev/min at varying brake mean effective pressures. Results showed that brake thermal efficiency of mahua oil ethyl ester was comparable to diesel. It was observed that the thermal efficiency at full load for diesel was 26.36%, whereas it was 28.3% for mahua oil methyl (MOME) and 26.42% for ethyl ester (MOEE). Emissions of hydrocarbon (HC), carbon monoxide (CO) and Bosch smoke numbers (BSN) were comparatively lower than that of diesel fuel. The highest reduction in HC emission observed in methyl ester was 60%, compared to 49% for ethyl ester. In the case of CO emission, 79% reduction was observed with methyl ester and 67% for ethyl ester. Oxides of nitrogen emission were comparatively lower and the data observed was 9% for methyl ester and 27% for ethyl ester, at full load. Based oil this study, it has been observed that esters of mahua oil could be used as a substitute for diesel.