CATALYST FOR PURIFYING NITROGEN OXIDE, AND APPARATUS AND FILTER FOR PURIFYING EXHAUST GAS OF INTERNAL COMBUSTION ENGINE

摘要

PROBLEM TO BE SOLVED: To provide a catalyst for purifying nitrogen oxide, in which an iridium particle is made to have a structure exhibiting oxidation resistance and a sintering suppressing effect so that high catalytic activity of the iridium can be kept.SOLUTION: The catalyst for purifying nitrogen oxide comprises such a catalyst particle 1 that the iridium particle 3 is deposited on the surface of a silicon carbide particle 2 and the iridium particle 3 is covered partially with an amorphous oxide layer 4, which is formed on the surface of the silicon carbide particle and contains SiOC. The purifying property of NOto be contained in exhaust gas can be improved by the catalyst for purifying nitrogen oxide and high NOpurifying property can be kept for a long period of time.SELECTED DRAWING: Figure 1