Influence of antioxidant additives on performance and emission characteristics of beef tallow biodiesel-fuelled C.I engine.

This work analyses the performance and emission characteristics of biofuelled compression ignition (C.I) engine with the implementation of an antioxidant. Using the transesterification process with sodium hydroxide as a catalyst, the beef tallow methyl ester (BTME) was obtained from the beef tallow oil. Poor physical properties of biodiesel (beef tallow oil (BTO)) namely high viscosity and density cause atomization problems leading to higher smoke, hydrocarbon and carbon monoxide emissions. The purpose of this work is to enhance the performance aspects, to limit smoke emissions from BTO operation and to examine the possibility of direct use of neat BTO in CI engine. This research paves a way of investing the impact of binary blends of BHA and BTO on the research engine. The experiments were conducted on a single-cylinder four-stroke C.I engine using the following fuel compositions: 20% of BTME mixed with 80% diesel (B20), 1000 ppm mono-phenolic antioxidant (butylated hydroxyanisole (BHA)) mixed with the blends of B20 (B20 + BHA), and 100% diesel. Based on the experimental results, it was found that the brake thermal efficiency (BTE) increases by 1.8% and the brake specific fuel consumption (BSFC) decreases by 2.5% for the fuel blend B20 + BHA when compared with that for B20 fuel blend. Compared with the B20 blend, the blend B20 + BHA emits 12.2% lesser nitrogen oxide due to breaking chain reactions, scavenging the initiating radicals and reducing the concentration of reactive radicals.