Process of producing chlorine dioxide
US5858322A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 28, 1997 |
| Grant date | Jan 12, 1999 |
| Priority date | — |
| Expiry date | Feb 28, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B11/025
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The invention relates to a process of producing chlorine dioxide comprising the steps: Providing a reactor with an aqueous acidic reaction medium containing alkali metal chlorate and sulfate; reducing chlorate ions in said reaction medium to form chlorine dioxide; maintaining the reaction medium at subatmospheric pressure sufficient to evaporate water and precipitate alkali metal sulfate; withdrawing chlorine dioxide and evaporated water from the reactor; withdrawing reaction medium containing solid alkali metal sulfate from the reactor and separating the solid material from said reaction medium; transferring reaction medium substantially free from solid alkali metal sulfate to an electrochemical cell in which the acidity of said reaction medium is increased and the content of alkali metal ions is decreased; recycling electrochemically acidified reaction medium to the reactor for producing chlorine dioxide; and adding make up alkali metal chlorate and sulfuric acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.