Recovery of concentrated H.sub.2 S from SO.sub.2 contained in flue gas
US4588567A · kind A · utility
Inventor
Key dates
| Filing date | Jan 28, 1985 |
| Grant date | May 13, 1986 |
| Priority date | — |
| Expiry date | Jan 28, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01D5/14
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
This invention is a regenerable process for producing gaseous hydrogen sulfide in concentrated form from sulfur dioxide obtained from a dilute gas source by (1) reacting the SO.sub.2 with a concentrated solution of Na.sub.2 SO.sub.3 to form Na.sub.2 S.sub.2 O.sub.5 in solution and then either: (2) reacting the Na.sub.2 S.sub.2 O.sub.5 with Na.sub.2 CO.sub.3 to form solid Na.sub.2 SO.sub.3, a concentrated solution of Na.sub.2 SO.sub.3 which is recycled to the SO.sub.2 reaction and concentrated gaseous CO.sub.3 which is used in a subsequent step, (3) reducing the Na.sub.2 SO.sub.3 to Na.sub.2 S, (4) reacting the Na.sub.2 S with solid NaHCO.sub.3 to form gaseous H.sub.2 S and Na.sub.2 CO.sub.3, (5) recycling part of the Na.sub.2 CO.sub.3 to (2) above and reacting the remainder with concentrated CO.sub.2 from (2) above to form solid NaHCO.sub.3 and recycling the solid NaHCO.sub.3 to (4) above, or; (2) reacting the Na.sub.2 S.sub.2 O.sub.5 with NaHCO.sub.3 to form solid Na.sub.2 SO.sub.3, a concentrated solution of Na.sub.2 SO.sub.3 which is recycled to the SO.sub.2 reaction, and concentrated, gaseous CO.sub.2 which is used in a subsequent step, (3A) reducing the Na.sub.2 SO.sub.3 to Na…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.