Process for preparing heavy oil hydroprocessing slurry catalyst
US4710486A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 21, 1985 |
| Grant date | Dec 1, 1987 |
| Priority date | — |
| Expiry date | Aug 21, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G49/18
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.