| 摘要 |
<p>" " A catalyst composition composed of a crystalline aluminosilicate Y zeolite, normally having a silica-to-alumina mole ratio of about 6.2 or above, in combination with a porous, inorganic refractory oxide. The Y zeolite contains ion-exchanged rare earth cations and ion-exchanged Group VIII noble metal cations. The combination of the zeolite and the refractory oxide contains between about 4.5 weight percent and about 6.5 weight percent water, preferably between about 4.5 and 6.0 weight percent. Such a catalyst containing the recited amount of water has been found to have consistently high activities when used as a catalyst in a hydrocracking process. The Y zeolites used as part of the catalyst are typically prepared by contacting an ammonium-exchanged Y zeolite with an aqueous solution of ammonium fluorosilicate.</p> |
