Patent ID: 8440141

Claim:
A treatment system of an exhaust gas containing a nitrogen oxide, CO and VOC, comprising: an exhaust gas treatment means for removing the nitrogen oxide by reduction thereof with ammonia and partially oxidizing the VOC to CO, and a CO/VOC removing means for oxidizing the CO and partially unreacted VOC, in this order from an upstream flow of the exhaust gas; wherein the exhaust gas treatment means comprises an exhaust gas treating catalyst comprising 60% by weight or more TiO 2 , 3 to 8% by weight V 2 O 5 , and 3 to 20% by weight WO 3 with respect to the total weight of the catalyst; and wherein the CO/VOC removing means comprises a CO/VOC removing catalyst comprising a honeycomb substrate and a porous inorganic compound layer thereon comprising a noble metal and an NMHC oxidation catalyst that is a TiO 2 —WO 3 compound or a TiO 2 —V 2 O 5 —WO 3 compound; and wherein the substrate comprises a porous inorganic compound unreactive to the nitrogen oxide, CO, and VOC, while the layer has reactivity to the CO and VOC.