Catalyst/hydrocarbon trap hybrid system

摘要

The invention is an automotive catalyst system for treating internal combustion engine exhaust gases. The system comprises a hybrid system of hydrocarbon trapping material and palladium based three-way catalyst material, the hydrocarbon trapping material being capable of adsorbing hydrocarbons present in said internal combustion exhaust gases and substantially maintaining adsorbance of the adsorbed hydrocarbons until after the palladium based three-way catalyst material reaches a temperature at which it is capable of oxidizing the hydrocarbons. The palladium based three-way catalyst is carried on a substrate, which may be the trapping material, in an amount of between about 100-500 g palladium/ft3 of substrate.