Process for recovering as sulfur the compounds H2S, SO2, COS and/or CS2 in a tail gas from a sulfur plant
US6444185B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 10, 2000 |
| Grant date | Sep 3, 2002 |
| Priority date | — |
| Expiry date | Aug 10, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B17/0469
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process is provided to recover residual H2S, SO2, COS and CS2 in the tail gas from a sulphur recovery process. The tail gas is oxidized and hydrolyzed at a temperature of from 180° C. to 700° C. to provide an oxidized and hydrolyzed gas stream containing substantially no COS or CS2 and having a concentration by volume of H2S and SO2 such that the H2S concentration minus twice the SO2 concentration is from 0.25% to 0.5%. Then the gas stream from the hydrolysis is passed over a Claus catalyst, for example based on alumina and/or titanium oxide, for the reaction of H2S with SO2 to form sulphur and provide a gas stream with substantially no SO2. The resulting gas stream from the Claus reaction together with a gas containing free oxygen is then passed over an oxidation catalyst, such as one of more oxides or salts of Ni, Co, Fe, Cu, Ag, Mn, Mo, Cr, W or V, deposited on a support, such as bauxite, activated aluminia, silica, titanium oxide, zirconium oxide, zeolite or activated carbon to form sulphur and release a purified gas stream containing substantially no sulphur compounds.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.