摘要 |
Y Zeolites are prepared with rare earth cations and Group VIII metal cations exchanged thereinto, such zeolites being especially useful in hydrocracking catalysts. The zeolites of the invention are prepared by exchanging a sodium Y zeolite with cations of one or more rare earth elements followed by a calcination, an ammonium ion exchange, and a Group VIII metal cation exchange. The resultant zeolite is not only highly active for catalytically promoting hydrocracking reactions but is also, after use in hydrocracking environments resulting in coke deposition, essentially completely regenerable by combustion of the coke. |