| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an exhaust emission control device, capable of preventing discharging of HCs(hydrocarbons) desorption from the HC adsorbent (zeolite or the like) contained in a catalyst, without purification by Catalyst element (precious metals or the like), when desorbing and purifying the HCs. SOLUTION: HC adsorption/desorption catalyst containing HC adsorbent, three-way catalyst and oxidation catalyst is provided with an HC-detecting means for estimating or computing the HC quantity adsorbed, HC saturated adsorbed quantity and HC desorption temperature, an HC desorption temperature control means for controlling HC desorption temperature and exhaust gas temperature to flow in, and an oxidation reaction enhancing means for increasing the oxidation reaction quantity of the three-way catalyst and the oxidation catalyst. When the HC-detecting means detects HCs, the hydrocarbon desorption temperature is increased to activate the oxidation reaction, which leads to desorption and purification of the hydrocarbons.</p> |
