Process for the production of polysulphide pulping liquor from pulp mill recovery smelt
US4153502A · kind A · utility
1Cited by
11References
18Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 1, 1978 |
| Grant date | May 8, 1979 |
| Priority date | — |
| Expiry date | May 1, 1998 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B17/34
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Sodium polysulphide is formed by reacting sodium sulphide and sodium sulphur-oxygen salts in the presence of carbon and oxygen. The invention is particularly applicable to reacting recovery furnace smelt from a polysulphide pulping process to form a mixture of sodium polysulphide and sodium carbonate which is substantially free from sodium sulphur-oxygen salts, so that dead-load sulphidity is substantially eliminated from the pulping liquor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.