Zeolite containing compositions, catalysts and methods of making

A hydrocarbon conversion catalyst comprising a particle-form aggregate of about 2-90% by weight of a stabilized, rare earth metal-free crystalline aluminosilicate zeolite component and about 10-98% by weight of an amorphous refractory inorganic oxide component selected from the class consisting of alumina, silica, magnesia, beryllia, zirconia, titania, thoria, chromia, and combinations thereof, said catalyst having been prepared by:

• a. ion exchanging a crystalline alkali metal aluminosilicate zeolite having a SiO.sub.2 /Al.sub.2 O.sub.3 ratio above 3 with ammonium ions under exchange conditions adjusted to reduce the alkali metal content of said zeolite to less than about 3 weight percent determined as the metal and replace between about 20% and 95% of the original alkali metal content of said zeolite with ammonium ions;
• b. steaming the resultant exchanged zeolite at a temperature of about 800.degree. to about 1650.degree.F in the presence of at least about 0.5 psi water vapor partial pressure for at least about 10 minutes, sufficient to convert said exchanged zeolite to the corresponding hydrogen form and stabilize said zeolite, said steaming being carried our prior to any calcination of said exchanged zeolite under anhydrous conditions and prior to the addition of said amorphous refractory inorganic oxide component;
• c. re-exchanging the resultant stabilized zeolite with ammonium ions under conditions sufficient to further reduce said alkali metal content to less than about 2 weight percent determined as the corresponding oxide and to introduce into said zeolite an amount of ammonium ions corresponding to at least about 5 percent of the original ion exchange capacity of said zeolite;
• and
• d. forming the re-exchanged zeolite into a particle-form aggregate containing said refractory oxide intimately admixed therein, and calcining said aggregate at a temperature of at least about 600.degree.F.