Catalyst composition for treating heavy feedstocks

A process for preparing a modified zeolite catalyst comprising forming a slurry of from 15 to 55 weight % of a matrix component selected from the group consisting of clays, synthetic matrix other than pillared clay, and mixtures thereof and from 10 to 20 weight % of a sol or gel of a binder selected from the group consisting of oxides of aluminum, silicon, and mixtures thereof and from 0 to 15 weight % of an oxide of a group IVB or VB metal adding thereto from 10 to 75 weight % of a mixture of one or more zeolites selected from the group consisting of:

• (i) not less than 10 weight %, based on the total weight of zeolites, of a zeolite having a silica to alumina ratio from 25 to 200 and up to 12 rings in a structural unit which has been treated with less than 0.5 molar alkaline solution at a temperature from 20° C. to 350° C. to reduce the silica to alumina ratio to less than 45, said alkaline treated zeolite having a meso-large pore BET surface area of greater than 50 m2/g;
• (ii) a zeolite having a silica alumina ratio from 10 to 70 and up to 12 rings in a structural unit and a meso large pore size BET surface area less than 40 m2/g;
• (iii) a beta zeolite having a structure in which the silica to aluminum ratio is less than 100;
• (iv) a Y-faujasite type zeolite having a structure in which silica to alumina ratio is less than 30;
• the sum of components (i), (ii), (iii) and (iv) adding up to 100 weight % of the zeolite components in said catalysts,
• wherein one or more of said zeolite components have been subjected to one or more of the following treatments
• (a) impregnating said zeolite with a phosphorus compound to provide from 0.2 to 15 weight % calculated as P2O5 based on the weight of the zeolite and either currently or subsequently treating the impregnated zeolite with steam or water at a temperature from 110° C. to 800° C. at a pressure from 103.3 kPa to 6.89×103 kPa for a time from 0.1 to 20 hours;
• (b) treating said zeolite with one or more group IVB, VB, VIB and VIII metal compounds to provide from 0.1 to 10 weight % of the metal based on the weight of the zeolite;
• (c) treating said zeolite with one or more rare earth compounds to provide from 0.1 to 10 weight % of the oxide of the rare earth metal based on the weight of the zeolite;
• forming particulates of said catalyst having a size from 0.001 to 0.8 mm.