EXHAUST GAS PURIFYING HEAT-RESISTANT HC ADSORBING MEMBER

摘要

PURPOSE:To provide an exhaust gas purifying HC adsorbing member having heat resistance and enhanced in HC adsorption capacity. CONSTITUTION:A HC adsorbing member 41 is obtained by forming an HC adsorbing layer 3 constituted of heat-resistant modified ZSM-5 zeolite to the inner surfaces of the respective cells 2 of a cordierite honeycmb 1. Modified ZSM-5 zeolite is obtained by applying aluminum removing treatment to unmodified ZSM-5 zeolite. When the SiO2/Al2O3mol ratio of unmodified ZSM-5 zeolite is set to Mr1, the SiO2/Al2O3mol ratio Mr2 of modified ZSM-5 zeolite is Mr2>=1.2Mr1 and modified ZSM-5 zeolite has the fundamental skeletal structure possessed by unmodified ZSM-5 zeolite.