Process for obtaining pure orthophosphoric acid from superphosphoric acid
US4083934A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 18, 1977 |
| Grant date | Apr 11, 1978 |
| Priority date | — |
| Expiry date | Jan 18, 1997 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/185
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for obtaining pure orthophosphoric acid from superphosphoric acid is provided comprising: PA1 (a) hydrolyzing superphosphoric acid with water until a mixture of polyphosphoric acids and orthophosphoric acid is formed, wherein the total P.sub.2 O.sub.5 content of said mixture is from 65% to 70% and the poly P.sub.2 O.sub.5 content of said mixture is from 1% to 15% of the total P.sub.2 O.sub.5 ; PA1 (b) crystallizing said orthophosphoric acid from said mixture; PA1 (c) separating said orthophosphoric acid from said mixture; and PA1 (d) washing said orthophosphoric acid with an organic solvent having a low or limited solubility for orthophosphoric acid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.