Catalytic combustion of diesel soot over perovskite-type catalyst: Potassium titanates

Abstract

Potassium titanates with a high crystallinity were successfully prepared by the sol-gel method and characterized by XRD, SEM, and BET surface area measurements. K6Ti4O11, K2Ti2O5, K2Ti4O9 were found to have better soot oxidation performance compared with Pt/TiO2 and CeO2 based catalysts. K2Ti2O5 may be an excellent candidate for soot oxidation due to its high oxidation activity, water-stability, resistance to sulfur poisoning and economical advantages. Certain amount of NO (x) can contribute to the catalytic combustion of diesel over potassium titanates, implying that K2TiO5 may be a kind of catalyst for simultaneous removal of NO (x) and soot.