The performance characteristics of groundnut (Arachis hypogea, L.) biodiesel in a diesel engine

The performance of groundnut ethyl ester blended with diesel in a compression ignition engine was experimentally determined. Groundnut oil reacted with ethanol to produce ethyl esters in a two-step transesterification process. The ethyl-esters were blended with automotive gas oil at (0 to 20%) mix with 5% increment of groundnut ethyl-esters to produce biodiesel. The performance of a 2.46 kW diesel engine was evaluated using the groundnut biodiesel at five loading conditions (0, 25, 50, 75 and 100% of full load). Automotive gas oil was used as a reference diesel fuel. The engine torque had a peak value of 8.5 Nm at full load, while the peak value of speed was 1300 rev/min at 25% full load when using 15% groundnut ester-AGO blend. The exhaust gas temperature had a peak value of 420°C at full load when using 5% groundnut ester-AGO blend. There were no significant differences (p>0.05) in average values of torque, speed and exhaust gas temperature of the engine for groundnut biodiesel and automotive gas oil. Groundnut biodiesel can be used to fuel a diesel engine.Key words: Groundnut oil, ethyl esters, biodiesel, diesel engine

Fuel properties of loofah (Luffa cylindrica L.) biofuel blended with diesel

Fuel properties of loofah oil and its ethyl ester blended with diesel were experimentally determined. Biodiesel blends (10, 20, 30, 40, 50, 60, 70, 80, 90 and 100%) of loofah oil and its ethyl ester by volume with diesel was used. The fuel properties of the biodiesel blends were determined according to American Society for Testing and Materials (ASTM) standards. Pure Automotive Gas Oil (AGO) was used as a reference fuel. The viscosity in the blends of loofah oil and its ethyl ester with AGO from B10 to B100 ranged from 4.5 - 43.1 mm2/s. It was observed that the viscosities of 10 - 40% loofah ester-diesel blends fell within limit specified by ASTM standards. The cloud points, the pour points and the flash points increased as the percentage of loofah oil and its ethyl ester increased in the blends. The specific gravity of all the loofah biodiesel blends ranged from 0.863 - 0.89 and fell within limit specified by international standards. The heating values of the loofah biodiesel blends decreased from 42.55 - 28.75 MJ/L. All the loofah biodiesel blends had sulphur contents ranging from 9.16 - 13.2% and lower than that of reference AGO. The ash content of all the biodiesel samples produced from loofah oil ranged from 0.01 - 0.02% and were lower compared to AGO obtained as 0.12. The blends of loofah ethyl ester (LEE) of B10 and B20 were found to have acceptable fuel properties to power compression ignition engines. Key words: Loofah ethyl esters, biodiesel, compression ignition engine, automotive gas oil (AGO)