Patent ID: 7442346
Filing Date: 2008-10-28
Classification: B01D,F01N,Y02A,Y02T

Abstract:
1. A catalyst system for the purification of exhaust gases from an internal combustion engine, consisting essentially of: (a) a catalyst A serving for the primary purification of the exhaust gases comprising a honeycomb carrier and a three-way catalyst formed thereon; (b) an adsorption catalyst B comprising: a honeycomb carrier; an adsorption layer formed thereon for the effective adsorption of hydrocarbons; and a catalyst layer comprising a noble metal selected from the group consisting of platinum, palladium and rhodium and at least one of ceria and alumina, wherein the catalyst layer is a separate layer applied to the adsorption layer and coating the adsorption layer, and wherein the adsorption catalyst B is located downstream of the catalyst A in the direction of the exhaust gas directly; (c) means, including a direct unbranched passageway between the catalyst A and the adsorption catalyst B, for conducting all the exhaust gas flowing out of the catalyst A to flow into the adsorption catalyst B at all time during operation of the catalyst system; and (d) means for supplying heat to the adsorption catalyst B from a heat source outside of the adsorption catalyst B, wherein the heat supplied from the heat source is supplied solely by the exhaust gases and the catalyst A.