Process for preparing crystalline ammonium dihydrogen phosphate
US4269814A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 1979 |
| Grant date | May 26, 1981 |
| Priority date | — |
| Expiry date | Aug 28, 1999 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/28
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for preparing crystalline ammonium dihydrogen phosphate, comprises the steps of (a) adding a sequestering agent into ammonium hydrogen phosphate aqueous solution, the sequestering agent reacting with metallic ions contained in the aqueous solution to form water soluble compounds, (b) heat-treating the aqueous solution at a temperature of 70.degree. C. or more after addition of the sequestering agent, and (c) crystallizing ammonium dihydrogen phosphate out of the aqueous solution after the heat-treating, so that crystalline ammonium dihydrogen phosphate can be obtained in high whiteness and in the form of columnar crystals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.