Comparison studies on sintering phenomenon of diesel oxidation catalyst depending upon aging conditions

Regulations of diesel engine exhaust gas were required vehicles of close to zero emission. It should be noted that diesel oxidation catalysts (DOCs) can be easily sintered by catalytic combustion using a high-temperature exhaust gas. The objectives of this study were to prepare correlation surface area of a Pt-based DOC with variously aging history and analyze its activity decay for the oxidation of NO. The result of this study showed that the deactivation mechanism of the prepared catalyst differs with thermal aging and oxidative thermal aging. It is sintering of DOC has two types activity decay on the oxidative thermal aging by sintering of active metal at shorted aging time and sintering of support after arbitrary aging time. The sintering of Pt was shown by TEM and XRD, and the sintering of the support structure was verified by XPS and XRD line-broadening. We conducted a study to determine the relationship between the sintering of the DOC and a loading amount of Pt.