Soot Oxidation Characteristics of SiC Nanoparticle Membrane Filters 2012-01-0848
A diesel particulate membrane filter (DPMF) has good trapping
efficiency of soot and reduces the pressure loss through the soot
accumulation process on the diesel particulate filter wall. The
activation energy reduction effect of the soot oxidation reaction
by DPMF was clarified. The membrane consists of SiC nanoparticles
with a diameter of 10-100 nm. A thin oxide layer is formed on the
SiC particle surface, and nanoscale noble metal particles are
distributed on the surface. The reduction mechanism for the
activation energy was investigated in detail.
Nanoscale soot was accumulated on DPMF from a diesel lamp.
Furthermore, the soot oxidation in the regeneration process was
observed using an optical microscope. An Arrhenius plot was made
from the change of the concentration of the product gases CO and
CO₂ with respect to time. The performance and the temperature
dependence of oxygen desorption on the oxide layer was measured by
thermal desorption spectroscopy (TDS).
Pt-CeO₂/ZrO₂-based materials are commonly used as oxygen storage
capacity (OSC) materials and the TDS chart shows two peaks of
oxygen desorption. However, the examined SiC exhibited only one
peak. It is expected that the oxygen-supply mechanism of this
material differs from the conventional reaction mechanism in OSC