Investigation on gas conversion efficiency and filtration behaviour of diesel oxidation catalysis system

Abstract

ABSTRACT The toxicity of automotive exhaust emissions can be reduced by pretreatment and post-treatment techniques out of which post-treatment techniques have proven to be more effective. A detailed study on the mechanism of reactions taking place inside the diesel oxidation catalysis (DOC) system is carried out in this paper. Experimental study has been carried out to determine the conversion efficiency of DOC system which is composed of cordierite substrate with a catalyst coating of platinum and palladium. Four DOC substrates with different catalyst loading have been used for experimentation and a comparative study has been conducted on the conversion efficiency of these substrates. Characterization of the DOC substrate is carried out using particle size analysis and atomic force microscopy techniques. Experimental analysis of the system is conducted in a multi-cylinder four stroke diesel engine with electrical dynamometer for loading. The results of experimental study showed that 400 cpsi ceramic DOC (35 g/ft3) has better conversion efficiency and performance among the DOC substrates considered in this work. Higher conversion efficiency is observed at full load condition which shows that the exhaust gas temperature plays a major role in the catalytic activity of DOC substrates.