| 摘要 |
PROBLEM TO BE SOLVED: To cooperate an adsorber with a catalytic system in a manner wherein exhaust gas in controlled over a whole operation period of an automobile, in a method controlling exhaust emission of the automobile provided with a catalyst unit for starting, adsorber and a main catalyst unit. SOLUTION: (1) Just after starting an automobile, by the order of first a starting catalyst unit 2 next an adsorber 3 or by the order of first the adsorber next the starting catalyst unit 2, the same exhaust gas flow is allowed to flow through. After flowing through the starting catalyst 2 and the adsorber 3, during the time when the adsorber 3 still has high adsorbing power, the gas is allowed to flow through a main catalyst unit 4 (here, the adsorber 3 maintains high adsorbing power at least till leading to a light off temperature of the starting catalyst unit 2). (2) At least, from a point of time when high adsorbing ability is not available in the adsorber 3, exhaust gas is directly guided to the main catalyst unit 4 from the starting catalyst unit 2 over a prescribed time range. |
