| abstract |
The purification apparatus of the present invention comprises at least one kind of noble metal selected from the group consisting of Pt, Pd and Rh and / or a first oxidation catalyst containing an oxide of the noble metal, silver and / or silver oxidation. Exhaust gas exhausted from an internal combustion engine including a silver-containing DPF catalyst containing a product, and at least one noble metal selected from the group consisting of Pt, Pd and Rh and / or a second oxide catalyst containing an oxide of the noble metal It is characterized by being arranged in this order from the upstream side to the downstream side. According to the purification device of the present invention, the function of the catalyst device can be maintained without deteriorating the function as a catalyst by replacing a part of the expensive noble metal with the silver catalyst. [Selection] Figure 1 |