Selective reduction of NO with CH
4 on platinum supported on cobalt phosphate was investigated. It was found that Pt/Co
3(PO
4)
2 exhibits the high activity to NO reduction with CH
4. NO conversion increased with increasing amount of Pt loading and it attained to a maximum activity at 1 wt% Pt. Conversion of NO was always higher than that of NO
2 on Pt/Co
3(PO
4)
2 under the same condition. This result suggested that the reduction of NO was proceeded not through the formation of NO
2 or NO
3− as intermediate species but through the direct decomposition of NO as a primary reaction. NO conversion increased with decreasing oxygen partial pressure and the high conversion of NO into N
2 was exhibited when no oxygen was coexisted. Temperature programmed desorption (TPD) measurement suggested that loading Pt accelerates the dissociative adsorption of NO and weakened the adsorption of O
2. Therefore, it seems that NO decomposition on Pt/Co
3(PO
4)
2 was initiated by the dissociative adsorption of NO. Coexisting CH
4 removed the formed oxygen which strongly adsorbed on the catalyst and recovered the active site. This study reveals that Pt supporting on Co
3(PO
4)
2 is highly active for the reduction of NO with CH
4.
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