Mild acidic catalyst for hydroprocessing of heavy crude oil and residue and its synthesis procedure

A method for the preparation of a hydroprocessing catalyst which comprises:

• a) preparation of a zeolite-alumina support by a dry mixing step consisting of dry mixing zeolite with different boehmites to obtain a dry mixture consisting of zeolite and alumina;
• b) adding water and nitric acid to peptize said boehmites and form a homogeneous paste;
• c) extruding the homogeneous paste into extrudates having a cylindrical shape;
• d) drying the extrudates;
• e) calcining the dried extrudates;
• f) incorporating metallic components of group VIB and group VIIIB into the dried extrudates using the aqueous incipient wetness impregnation method;
• g) drying the impregnated extrudates;
• and h) calcining the catalyst.

A method for the preparation of a hydroprocessing catalyst for processing heavy crudes and residua, which comprises preparing a support consisting of SiO2—Al2O3 by homogeneous precipitation of SiO2—Al2O3 which comprises:

• a) mixing aqueous solutions of sodium silicate solution (2-5 molar SiO2) and aluminum nitrate (2-5 molar Al2O3) by vigorous stirring to form an acidified gel solution;
• b) adding an aluminum solution in the presence of a basic precipitant to the acidified solution to form a gel and increase pH above 3 for co-gelation of silica and alumina species at a constant pH of 4 to 8;
• c) adding a sufficient quantity of precipitant at the end of the co-gelation to obtain a final pH of the solution in the range of 8 to 9 and complete the reaction and form a solid co-gel mass;
• d) aging the solid co-gel mass at a temperature in the range of 60 to 80° C. to convert the co-gel mass into a sol;
• e) filtering the solid mass of silica-alumina (sol-gel) from the mother liquor;
• f) washing the solid mass with water to remove sodium ions from the co-gel;
• g) processing the sol using wet extrusion method to form extrudates;
• h) drying the extrudates;
• i) calcining the extrudates to form a support consisting of two-component silica-alumina;
• j) impregnation of the silica-alumina support with an active metal with the incipient wetness method using a group VIB metal in a first step and a group VIIIB in a second step to form an impregnated silica-alumina catalyst;
• k) drying the impregnated silica-alumina catalyst to form a dried impregnated silica-alumina catalyst;
• and 1) calcining the dried impregnated silica-alumina, wherein said support is an amorphous silica-alumina having approximately 5 to 50 weight percent SiO2 and a Si/Al ratio of 0.2 to 1.25.

A method for the preparation of a hydroprocessing catalyst which comprises:

• a) preparation of a zeolite-alumina support by a dry mixing step a) which consists of mechanically mixing boehmites and USY zeolite;
• b) adding nitric acid and distilled water to peptize said alumina and form a homogeneous paste;
• b) extruding the paste to obtain extrudates having a cylindrical shape;
• c) drying the extrudate at 100-120° C. for 12-15 hours;
• d) calcining of the dried extrudates at 500-550° C. with excess air to obtain a gamma alumina support;
• e) successive impregnation of the supports, first with ammonium heptamolybdate and then with nickel nitrate;
• f) aging of the resulting solids for 12-18 hours at room temperature to obtain aged solids;
• g) drying the aged solids at 100-120° C. to obtain dried solids;
• h) calcining the dried solids to obtain a calcined support;
• i) impregnating the calcined support by sequential impregnation with a group VIB metal, followed by a group VIIIB metal to obtain a promoted catalyst;
• j) drying the promoted catalyst at a temperature between ambient temperature and 120° C. to obtain a dried promoted catalyst;
• and k) calcining the dried promoted catalyst.