Hydroprocessing catalysts and methods for making thereof

A process for preparing a slurry catalyst having improved catalytic activities for use in the upgrade of heavy oil feedstock, comprising:

• providing at least a solution comprising at least a water-soluble metal precursor salt of at least a Group VIB metal, the solution having a concentration of less than 10 wt. % of the at least Group VIB metal in the solution;
• sulfiding the at least a solution with a sulfiding agent, forming a sulfided catalyst precursor;
• mixing the sulfided catalyst precursor with a hydrocarbon diluent to form a slurry catalyst;
• mixing a hydrogen feed with the slurry catalyst at a pressure from 1435 psig (10 MPa) to 3610 psig (25 MPa) and a temperature from 200° F. to 800° F. at a rate of from 500 to 15,000 scf hydrogen per bbl of slurry catalyst for a minute to 20 hours ,
• wherein the slurry catalyst is saturated with hydrogen providing an increase of k-values in terms of HDS, HDN, and HDMCR of at least 15% compared to a slurry catalyst that is not saturated with hydrogen.

A method for improving the porosimetry of a slurry catalyst, comprising:

• providing a slurry catalyst having an average particle size ranging from 1 to 300 μm, prepared from a solution comprising at least a water-soluble metal precursor salt of any of a Group VIB metal and a Group VIII metal, and sulfided by a sulfiding agent under sulfiding conditions at a molar ratio of sulfur to metal of at least 1.5:1;
• and
• pretreating the slurry catalyst by mixing with the hydrogen feed at a pressure from 1435 psig (10 MPa) to 3610 psig (25 MPa) and a temperature from 200° F. to 800° F. at a rate of from 500 to 15,000 scf hydrogen per bbl of slurry catalyst for a minute to 20 hours,
• wherein the slurry catalyst treated with hydrogen provides an increase of rate constant k-values in terms of HDS, HDN, and HDMCR of at least 10% compared to a slurry catalyst that is not treated with hydrogen.