Exhaust gas post processing apparatus

An exhaust gas post processing apparatus mounted on an exhaust pipe connected to an exhaust side of an engine to purify exhaust gas of the engine in a gasoline vehicle, the apparatus comprising:

• a housing mounted on the exhaust pipe to receive the exhaust gas discharged from the engine and to exhaust the exhaust gas passed rearward the housing;
• a front end honeycomb catalyst unit embedded in the housing to purify the exhaust gas introduced into the housing through a front end portion of the housing;
• and
• a rear end honeycomb catalyst unit embedded in the housing and mounted in a rear of the front end honeycomb catalyst unit to further purify the exhaust gas purified via the front end honeycomb catalyst unit before flowing out to a rear end portion of the housing,
• wherein the front end honeycomb catalyst unit includes a powder type catalyst including an IRA powder catalyst (IrRu/Al2O3), in which an iridium-ruthenium alloy (IrRu) is supported on an aluminum oxide (Al2O3) support powder, and
• wherein the rear end honeycomb catalyst unit includes three-way catalyst (TWC) powder which removes carbon monoxide, nitrogen oxides, and hydrocarbons.