Catalytic diesel soot oxidation by hydrothermally stable glass catalysts

Abstract

K–Ca–Si glass coated cordierite catalyst was exposed to extended continuous soot oxidation testing in a bench top reactor utilizing flame soot deposition. These samples maintained a T50 temperature of 500 °C at the end of an estimated 100,000 mi equivalent continuous soot oxidation testing in a low humidity environment. High temperature (500–700 °C) hydrothermal exposure led to potassium and calcium carbonate formation on the glass catalyst surface which degraded oxidation activity with increasing hydrothermal temperature up to 700 °C due to reduced potassium surface mobility. The presence of a soot layer during hydrothermal exposure shielded the glass surface from extensive deactivation, suggesting glasses as promising catalysts for extended DPF use.