Comprehensive Analysis of Fuel Properties of Biodiesel from Croton megalocarpus Oil

Abstract

Of late, much emphasis has been placed on searching for alternative fuels and significant investigations have been carried out regarding the production of biodiesel, especially from non-edible vegetable oils, with a view to minimize the dependence upon liquid hydrocarbon fuels, reduce emissions, and boost the rural economy. In this paper, the properties of Croton megalocarpus oil methyl ester (COME) from C. megalocarpus seed oil (non-edible) were investigated to determine their suitability for use as a petrodiesel substitute. C. megalocarpus seed oil was found to contain free fatty acids (FFAs) of 1.73%, which was below the 2% recommended for the application of the one-step base-catalyzed transesterification method. The transesterification process was carried out at the following optimized conditions: methanol/oil molar ratio (mol/mol), 6:1; potassium hydroxide, 1.0 wt %; reaction temperature, 50 °C; agitation speed, 500 rpm; and reaction time, 60 min. COME obtained was analyzed by gas chromatography (GC) to determine the methyl ester yield. COME offered the maximum methyl ester yield of 89.6%. The fuel-related properties of COME, cold filter plugging point (CFPP), cloud point (CP), kinematic viscosity, lubricity, oxidative stability, cetane number, flash point, acid value, density, calorific value, and free and total glycerol, were determined and discussed in light of biodiesel standards, such as ASTM D6751 and EN 14214. The most remarkable feature of COME was the CFPP and CP, which were −11 and −6 °C, respectively. The good cold flow properties of COME demonstrate its operational viability during the cold season. Tribological results showed that the lubrication ability of COME was better than that of conventional diesel fuel. However, COME did not fulfill the oxidative stability requirements of ASTM D6751 and EN 14214.