The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 01, 1987
Filed:
Aug. 21, 1985
Jaime Lopez, Benicia, CA (US);
Eugene A Pasek, Export, PA (US);
Chevron Research Company, San Francisco, CA (US);
Abstract
A process for the preparation of a dispersed Group VIB metal sulfide hydrocarbon oil hydroprocessing catalyst comprising reacting aqueous ammonia and a Group VIB metal compound, such as molybdenum oxide or tungsten oxide, to form a water soluble oxygen-containing compound such as aqueous ammonium molybdate or tungstate. The aqueous ammonium molybdate or tungstate is sulfided in at least three sulfiding steps of increasing temperature including a low temperature sulfiding step, an intermediate temperature sulfiding step and a high temperature sulfiding step. Some of the oxygen associated with said Group VIB metal is replaced by sulfur in each of the sulfiding steps. It has been found the maximum total level of replacement of oxygen by sulfur achieved in the intermediate temperature step is particularly critical to catalyst activity. In accordance with this invention, in the intermediate temperature sulfiding step the maximum total stoichiometric level of replacement by sulfur of oxygen associated with the Group VIB metal reaches a level of 50 to 95 percent. Additional replacement of oxygen with sulfur occurs in the high temperature sulfiding step.