Continuous in-situ combination process for upgrading heavy oil
US5935421A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 1996 |
| Grant date | Aug 10, 1999 |
| Priority date | — |
| Expiry date | Oct 21, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G67/02
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention relates to an integrated, continuous process for the removal of organically bound sulfur (e.g., mercaptans, sulfides and thiophenes) comprising the steps of contacting a heavy oil, sodium hydroxide, hydrogen and water at a temperature of from about 380.degree. C. to 450.degree. C. to partially desulfurize the heavy oil and to form sodium sulfide, contacting said sodium sulfide via steam stripping to convert the sodium sulfide to sodium hydroxide and the sulfur recovered as hydrogen sulfide. The sodium hydroxide is recirculated for reuse. The partially desulfurized, dewatered heavy oil is treated with sodium metal under desulfurizing conditions, typically at a temperature of from about 340.degree. C. to about 450.degree. C., under a hydrogen pressure of at least about 50 psi to essentially desulfurize the oil, and form sodium sulfide. Optionally, the sodium salt generated can be regenerated to sodium metal using regeneration technology. The process advantageously produces essentially sulfur-free product oils having reduced nitrogen, oxygen and metals contents and reduced viscosity, density, molecular weight and heavy ends.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.