VEHICULAR POLLUTION CONTROL - REDUCTION OF CARBON-MONOXIDE

Abstract

Noble metals in the form of pellets or monoliths are often used in catalytic converters to promote pollutant removal from the vehicular exhaust ',USA, Japan, European Union countries, with the emission regulation becoming stricter in other countries as well . The focus of research has been shifted towards base metal Oxides (simple and mixed) as a cheap alternative to noble metals Amongst the mixed oxides, perovskites having structure ABO3( A is big cation and B smaller Cation) are considered the nearest rival of noble metals because of some of their unique characteristics, such as their chemical tailoring to suit the specific requirements and their better thermal stability than the noble metals. In this work, the catalytic activity of mixed metal oxides having perovskite and related structure for oxidation of CO has been studied. A number of catalysts having Co, Fe, Cr, 131 at B-site and La, Ca and Ba site were prepared from their nitrate precursors using co-precipitaion techniques and specified heating cycle. Bench scale continuous flow reactor studies was conducted using simulated exhaust gases stream having carbon monoxide, propylene and oxygen as the main components in a representative concentration. The maximum carbon monoxide conversion efficiency of 100% was observed at as low as 200 °C in 10% LaCoO3/Zr02.