Exhaust gas purifying system and method

A flow-through monolithic catalyst for use in an exhaust gas purifying system, comprising:

• a first section functioning to adsorb and oxidize a soluble organic fraction in exhaust gas;
• a second section functioning to adsorb nitrogen oxides in exhaust gas in a condition in which a temperature of exhaust gas is not higher than 200° C.;
• and
• a third section functioning to allow carbon particle in exhaust gas to pass through the monolithic catalyst.

A method of purifying exhaust gas flowing through an exhaust gas passageway, comprising:

• a first process accomplished in a flow-through monolithic catalyst disposed in the exhaust gas passageway, including
• adsorbing and oxidizing a soluble organic fraction in exhaust gas,
• adsorbing nitrogen oxides in exhaust gas in a condition in which a temperature of exhaust gas is not higher than 200° C.,
• allowing carbon particle in exhaust gas to pass through the monolithic catalyst;
• and
• a second process accomplished in a filter catalyst disposed in the exhaust passageway downstream of the flow-through monolithic catalyst, including
• trapping the carbon particle in exhaust gas, and
• oxidizing hydrocarbons, carbon monoxide and nitrogen monoxide in exhaust gas.