Process and apparatus for the production of sulphuric acid and alkali metal hydroxide
US5423959A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 22, 1994 |
| Grant date | Jun 13, 1995 |
| Priority date | — |
| Expiry date | Jun 22, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC25B1/22
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The present invention relates to an electrochemical process for the production of sulphuric acid and alkali metal hydroxide, from an aqueous anolyte containing alkali metal sulphate. According to the invention, crystalline alkali metal sulphate is added to the anolyte, whereby the concentration of water can be maintained below about 55 percent by weight. In the electrolysis, the anolyte is brought to an electrochemical cell with a cation exchange membrane. In the cell, sulphuric acid and oxygen are formed in the anode compartment and alkali metal hydroxide and hydrogen in the cathode compartment. The steps normally preceding the electrolysis, i.e. dissolution and purification of the sulphate can be disposed of, since the process is less sensitive to impurities than the processes of the prior art. The present invention also relates to an apparatus for the production of sulphuric acid and alkali metal hydroxide according to the invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.