Combustion of soot deposits from diesel engines on mixed oxides of vanadium pentoxide and cupric oxide

Abstract

The catalytic combustion of diesel soot has been studied under the influence of mixed oxides of V 2O 5 and CuO on a carrier of γ-alumina. A mixture of diesel soot and catalyst was placed in a flow reactor and a gas mixture containing 10% oxygen, 7% water and balance of nitrogen was led through it at a flow-rate of 90 l/h. The combustion rate of the soot was determined between 573 and 698 K. The results showed that a mixed oxide of V 2O 5 and CuO with a molar fraction of 0.9 in vanadium has the highest activity. Small amounts of platinum (<0.1 wt.-%) dispersed on the metal oxide phase through decomposition of H 2PtCl 6 in a reducing atmosphere enhance the catalyst's ability to combust hydrocarbons and carbon monoxide greatly. In addition, the catalyst is not sensitive to sulphur poisoning. A catalyst for the combustion of diesel soot should therefore be based on a mixed oxide of V 2O 5 and CuO, promoted with small amounts of platinum.