Process for manufacture of calcium hypochlorite
US3954948A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 6, 1975 |
| Grant date | May 4, 1976 |
| Priority date | — |
| Expiry date | Jan 6, 1995 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B11/064
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A continuous process for the manufacture of calcium hypochlorite in which an aqueous slurry of lime and sodium hypochlorite is chlorinated in a mixing zone to form a sodium chloride solution containing large crystals of calcium hypochlorite which are readily separated and dried. The resulting solution containing some dissolved calcium hypochlorite is reacted with an alkali metal hydroxide to precipitate lime, which is separated and recycled to the mixing zone slurry. The lime-free solution may be used as bleach liquor or processed to precipitate solid salt useful in the preparation of brine. The remaining solution is recycled to the mixing zone slurry. Purification of fresh lime is also disclosed. The process provides an improved separation of calcium hypochlorite and sodium chloride, and recycles all solutions to minimize pollution of water resources.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.