Calcium chloride purification
US7037480B2 · kind B2 · utility
8Cited by
8References
11Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Apr 8, 2004 |
| Grant date | May 2, 2006 |
| Priority date | — |
| Expiry date | Oct 22, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/915
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Significant amounts of soluble fluoride, known to create problems in processes requiring high quality grade calcium chloride, are removed from calcium chloride solution using hydroxyapatite as a removal mechanism. Under acidic conditions, calcium chloride solution is purified to about less than 10 ppm fluoride, significantly, to less than 1 ppm fluoride. At least 0.1 weight percent hydroxyapatite and concentrated hydrochloric acid are added to calcium chloride solution and slurried to remove fluoride and create a highly purified calcium chloride solution, substantially free of fluoride.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.