| 摘要 |
<p>The present invention relates to a process for preparing a modified Y-zeolite, in which an NaY-zeolite is first subjected to an ammonium exchange, the resulting ammonium exchanged zeolite is subjected to an aluminium exchange, the aluminium exchanged zeolite is subjected to a steam calcination, and a phosphorus component is incorporated into the steam calcined zeolite. The Y-zeolite obtainable by said process and an FCC catalyst comprising said Y-zeolite are also claimed. The FCC catalyst comprising the aluminium exchanged phosphorus-containing Y-zeolite according to the invention shows less coke make, and an improved selectivity to C3 olefins compared to FCC catalysts comprising zeolites which have either been aluminium exchanged or comprise phosphorus.</p> |
