| abstract |
Exhaust gas purification catalyst device capable of efficiently purifying particulate components such as hydrocarbons, carbon monoxide, nitrogen oxides, soot, etc. contained in exhaust gas from lean combustion engines for a long period of time, such exhaust gas purification An exhaust gas purification method using a catalyst device and a diesel vehicle equipped with the exhaust gas purification catalyst device are provided. An oxidizing catalyst (DOC) containing a noble metal component for oxidizing nitrogen oxide (NO) in exhaust gas discharged from a diesel engine, a reducing agent spraying means for supplying a reducing agent selected from a urea component or an ammonia component, and In the exhaust gas purification catalyst device in which selective reduction catalyst (SCR) for reducing nitrogen oxide (NOx) in contact with a reducing agent is arranged in this order from the upstream side of the exhaust gas passage, the selective reduction catalyst (SCR) is a zeolite or crystalline metal aluminophosphate containing no precious metal component, and a trap means for collecting the precious metal component volatilized from the oxidation catalyst (DOC) is selected as the oxidation catalyst (DOC) Provided by an exhaust gas purification catalyst device or the like characterized by being disposed between reduction catalysts (SCR). [Selection] Figure 1 |