Microscopic Visualization and Analysis of Particulate Matter Trapping and Oxidation on a Diesel Particulate Filter and a Membrane Filter

Abstract

A diesel particulate membrane filter (DPMF) was proposed to improve the filtration performance and to reduce the oxidation temperature of soot. It consists of two-layer sintered filters, where a SiC-nanoparticle membrane covers the surface of a conventional SiC filter. Soot trapping and oxidation on the surface of the DPMF were investigated in detail using an optical microscope and exhaust gas analysis, and were compared with those of the conventional DPF. The membrane layer plays a significant role for filtration performance because it acts like a soot cake layer. Moreover, the DPMF had some catalytic activity for soot oxidation.