Process for treating the mother liquor by cooling in the production of anhydrous sodium dithionite
US4042674A · kind A · utility
4Cited by
2References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 18, 1976 |
| Grant date | Aug 16, 1977 |
| Priority date | — |
| Expiry date | May 18, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B17/66
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
In the production of anhydrous sodium dithionite by reacting sodium formate, an alkaline sodium compound and sulfurous acid anhydride in hydrous methanol, a process for treating the mother liquor, which comprises cooling the mother liquor left after the separation of the resulting anhydrous sodium dithionite to a temperature in the range of +5.degree. to -30.degree. C, and separating the precipitated sodium thiosulfate by filtration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.