| 摘要 |
<p>Zeolite Y comprising aluminum ions supplied and fixed by ion-exchange is produced by subjecting zeolite NaY to a series of treatment steps comprising int. al. ammonium ion-exchange and calcination. In order to supply and fix the aluminum ions, an aluminum ion-exchange is carried out, followed by further calcination in a saturated or substantially saturated water vapour (steam) atmosphere at 400-900°C. If the zeolite unit cell size is to be reduced to 24.15-24.35 Å, simultaneously as the aluminum ions are fixed, the last-mentioned calcination is carried out in a saturated or essentially saturated water vapour (steam) atmosphere at 500-900°C.</p> |
