Effects of different catalysts on light-off temperature of volatile organic components in the rotary diesel particulate filter during the regeneration

Abstract

In this work, the rotary diesel particulate filter (DPF) is used as the research object, and the effects of different mass fractions of Pd and Pt catalysts and different test conditions on the light-off temperature in regeneration process are investigated through the CHEMKIN software. The results show that the light-off temperature of volatile organic components in the Pd-catalyst rotary diesel particulate filter is 110 K lower than that in the rotary diesel particulate filter without catalyst. The light-off temperature decreased with the increase of catalyst mass fraction. Pd-based catalysts with mass fractions of 0.1%, 0.5%, and 1.0% had significantly higher effects on CH4 combustion than Pt-based catalysts. While Pt-based catalysts with mass fraction of 2.0% show the best light-off performance among all catalysts. The conversion rate of the 2.0% Pt-based catalysts reaches 62.27% at 623 K and 100% at 698 K. The research results under different test conditions show that Pd dispersion around 70% has the lowest light-off temperature. The light-off temperature of CH4 is lower at lower air flow rates. As the air flow increases, the light-off temperature increases. The intake pressure and HC concentration have small effects on the light-off temperature of CH4. The increases of water vapor volume fraction lead to a gradual increase in the light-off temperature of CH4.