HIGHLY HEAT RESISTANT BETA- ZEOLITE AND ABSORBENT FOR AUTOMOBILE EXHAUST GAS PURIFICATION AND ADSORBENT FOR AUTOMOBILE EXHAUST GAS PURIFICAT

摘要

A highly heat-resistant and hydrothermal-resistant &bgr;-zeolite having a SiO₂/Al₂O₃ ratio of 80 or more, which is constituted by primary particles having an average particle diameter of 30 nm or more or by primary particles having such a particle size distribution that the 10% particle diameter is 20 nm or more; and an adsorbent for automobile exhaust gas purification, using said &bgr;-zeolite. The &bgr;-zeolite and the adsorbent can be produced reliably so as to have quaranteed properties.