| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus in which the detachment of platinum can be suppressed even if the platinum is carried in an oxide catalyst or a filter.SOLUTION: In an exhaust gas postprocessing apparatus for an engine having an oxide catalyst (23) containing at least platinum and a filter (24) for collecting particulate in exhaust gas, at the upstream side and including a selective reduction type NOcatalyst (25) which reduces and purifies NOin the exhaust gas by adding a reducing agent, an air excess ratio control means (11) is provided to restrict and control an air excess ratio within a predetermined range when a temperature of the oxide catalyst (23) exceeds a predetermined temperature. |
