Purification of alkali metal hydroxides
US4372924A · kind A · utility
1Cited by
11References
17Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 27, 1980 |
| Grant date | Feb 8, 1983 |
| Priority date | — |
| Expiry date | May 27, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J8/0453
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method to purify an aqueous solution of an alkali metal hydroxide by countercurrently contacting the ammonia and hydroxide, in a volume ratio of about 0.6 to 1 to about 1 to 1, in a packed bed. The temperature in the lower portion of an extractor in which the process is carried out is controlled and maintained within a range of at least about 155.degree. to about 170.degree. F.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.