| 摘要 |
An exhaust gas purification apparatus includes an exhaust gas passage, a first oxidation catalyst, a selective catalytic reduction catalyst, an oxidation-reduction catalyst and a urea water supply device. Exhaust gas is flowed through the first oxidation catalyst. The first oxidation catalyst is disposed in the exhaust gas passage. The selective catalytic reduction catalyst is disposed downstream of the first oxidation catalyst. The oxidation-reduction catalyst is disposed downstream of the selective catalytic reduction catalyst. The oxidation-reduction catalyst has reducing property and oxidizing property which are influenced by temperature, wherein the oxidizing property of the oxidation-reduction catalyst is greater than the reducing property of the oxidation-reduction catalyst under a temperature that is higher than a temperature under which the reducing property of the oxidation-reduction catalyst is greater than the oxidizing property of the oxidation-reduction catalyst. The urea water supply device supplies urea water upstream of the selective catalytic reduction catalyst. |
