Abstract: A catalyst for the hydrotreatment of heavy crudes and their residues, and a method of preparing same, is disclosed, which has significant simultaneous hydrodemetallizing and hydrodesulfurizing activity. The catalyst is prepared by successively impregnating an extruded refractory support with a Group VIb and a Group VIII metal, calcining the pellet thus produced, and presulfurizing same. Pore volume of the catalyst ranges between 0.50 and 1.2 ml/g, total surface area ranges between 120 and 400 m.sup.2 /g, at least 60% of said pore volume consists of pores having diameters greater than 100 .ANG., and X-ray photoelectron spectroscopy signal band strength ratios are as follows: I(Me VIb)/I(refractory metal) is between 5 and 8, and I(Me VIII)/I(refractory metal) is between 1 and 5.

Abstract: A catalyst for the hydrotreatment of heavy crudes and residues and a method for the preparation thereof are claimed, specifying an amount of Group VIb metallic hydrogenation compound irreversibly absorbed by the silica or alumina extruded support structure surface to be between 0.5 and 3% of the dried and calcined catalyst by weight. The percentage limit on the hydrogenation compound can be achieved by either obtaining a dense alumina support structure having a novel pore diameter distribution, or treating a prior art support with an absorption site restricter such as MgO prior to hydrogenation compound impregnation. Subsequent fabrication steps comprise washing, drying, calcining and presulfurizing. The resultant catalyst has a monolayer of hydrogenating compound deposited on the reaction surface, and interfering compounds such as massive MoO.sub.3, Al(MoO.sub.4).sub.3 or polymolybdates are not formed.

Abstract: The invention relates to a particular method for the preparation of a hydrocracking catalyst, using a high iron content bauxite as a basis. This bauxite is ground and screened to a specific size and mixed with three types of additives: a promoter additive of the P, Mo, Co, Ni, W type. A hardener additive of the phosphoric acid type, ammonium phosphate. And a lubricant and pore-generating additive of the polyvinyl alcohol, polyethylene-glycol, starch type. The particularity consists in that the three additives are added simultaneously during the extrusion of the sample. That way, a particular surface composition is obtained which allows for the activity of the catalyst. Extruded products are obtained in sizes of 1/8, 1/16, and 1/32" and submitted to drying and calcination programs for their activation.The obtained catalyst offers a good mechanical strength, a high content in macropores and a high activity, specifically for the hydrocracking of heavy Venezuelan crudes or residues.