Process for the preparation of a hydrocracking catalyst
This invention relates to a process for the preparation of a hydrocracking catalyst and its use. A zeolite Y having specifically defined properties is mixed with an alumina binder component and a first metals-containing solution that is extruded to form an extruded mixture. The extruded mixture is dried and calcined. The dried and calcined mixture is then impregnated with a second metals-containing solution.
1. A process for the preparation of a hydrocracking catalyst, which comprises the steps of:
(a) mixing a zeolite Y, having a unit cell size in the range of from 24.42 to 24.52 Å, a bulk silica to alumina molar ratio (SAR) in the range of from 10 to 15, and a surface area of from 910 to 1020 m 2 /g, with an alumina binder component, a first Group VIB metal component, and a first Group VIII metal component, which at least one of the metal components is contained in at least one first metal-containing acidic aqueous solution, to thereby provide a mixture, wherein the zeolite Y is present in the mixture in an amount of 40 wt. % or greater, based on the total weight of the zeolite Y and the alumina binder component;
(b) extruding the mixture to provide an extruded mixture;
(c) drying the extruded mixture to provide a dried and extruded mixture;
(d) calcining the dried and extruded mixture to provide a calcined product;
(e) impregnating the calcined product with a second Group VIB metal component and a second Group VIII metal component, which at least one of the metal components is contained in at least one second metal-containing solution to provide an impregnated product; and
(f) calcining the impregnated product at a temperature in the range of from 350° C. to 850° C.
2. A process according to claim 1 , wherein the impregnation in step (e) is carried out in the presence of a hydroxy carboxylic acid.
3. A process according to claim 2 , wherein the hydroxy carboxylic acid comprises gluconic acid, malic acid, tartaric acid, citric acid or a mixture thereof.
4. A process according to claim 3 , wherein the hydroxy carboxylic acid is citric acid or malic acid.
5. A process according to claim 1 , wherein the second metals-containing solution comprises the hydroxy carboxylic acid.
6. A process according to claim 5 , wherein the hydrocracking catalyst comprises Group VIB metal in an amount in the range of 10-24 wt. %, and a non-noble Group VIII metal is present in an amount in the range of from 3-10 wt. %, both weights being based on the total weight of the hydrocracking catalyst.
7. A process according to claim 6 , wherein the first metal-containing solution, comprises nickel and tungsten, and the second metal-containing solution, comprises nickel and a Group VIB metal selected from the group consisting of tungsten and molybdenum.
8. A process according to claim 7 , wherein step (c) is carried out at a temperature in the range of from 100° C. to 300° C.
9. A process according claim 1 , wherein step (d) is carried out at a temperature in the range of from 500° C. to 850° C.
10. A process according to claim 1 , wherein the calcined product as obtained in step (f) is subjected to a sulfidation step.
11. A process for hydrocracking a hydrocarbonaceous feedstock, which process comprises contacting the feedstock at elevated temperature with a hydrocracking catalyst as prepared by a process as claimed in claim 1 .
12. A process according to claim 11 , which process comprises contacting the feedstock with the catalyst composition at a reaction temperature in the range of from 250 to 500° C. and a total pressure at the reactor inlet in the range of from 3 ×10 6 to 3 ×10 7 Pa.