Novel hydrocracking or cracking catalyst for hydrocarbon charges

Claim 1

A catalyst containing by weight (a) about 20 to 98% of a matrix comprising alumina, silica, silica-alumina, alumina boron oxide, magnesia, silica-magnesia, zirconia, titanium oxide, or clay, (b) about 2 to 80% of a zeolite having: a molar ratio SiO 2 /Al 2 O 3 between about 12 and 40; a sodium content less than 0.15% by weight determined on the zeolite calcined at 1100° C.; a parameter ao of the elementary mesh comprised between 24.38×10 -10 m and 24.26×10 -10 m; a sodium ion take-up capacity ONa expressed in grams of sodium per 100 grams of zeolite modified, neutralized and calcined higher than about 0.85%; a specific surface higher than about 550 m 2 (g); a water vapor adsorption capacity at 25° C. (at a P/Po ratio equal to 0.10) higher than 6%; (c) 0.01-5% b.w. of at least one noble Group VIII metal or metal compound, or 0.01-15% by weight of at least one group VIII non-noble metal or metal compound, said catalyst being produced by a process consisting essentially of mixing said matrix with said zeolite and introducing in one or several steps into the matrix, into the zeolite or into a mixture thereof, one or more metals or compounds of metals of group VIII or a mixture of metals of group VIII and group VI, and wherein the preparation of the zeolite consists essentially of lowering the sodium level of a NaY-zeolite to a value below 2.5% by weight by at least one exchange with a solution of an ionizable ammonium salt, so as to obtain an NH 4 NaY zeolite; calcining in at least one step the NH 4 NaY zeolite (hydrothermic treatment) between about 770° and 780° C., at a partial water vapor pressure between about 0.1 and 5 bar for at least 1 hour to obtain a stabilized zeolite, and treating the stabilized zeolite in at least one step by at least one solution of an organic or inorganic acid, whereby the resultant zeolite has a pore distribution comprising between 1 and 20% of the pore volume contained in pores of diameter situated between 20×10 -10 and 80×10 -10 m, the remainder of the pore volume being essentially contained in pores of diameter less than 20×10 -10 m.