Process for producing phosphorus pentoxide or phosphorus or phosphoric acid
US4351813A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 1981 |
| Grant date | Sep 28, 1982 |
| Priority date | — |
| Expiry date | May 20, 2001 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for producing phosphorus pentoxide from phosphate ores in a rotary-type kiln includes heating, by exposure to a flame, a porous bed comprising phosphate ore and solid carbonaceous material to a temperature sufficient to reduce the phosphorus pentoxide to phosphorus vapor. The phosphorus vapor is oxidized in an oxidation zone disposed over the porous bed to heat the porous bed. An inert gas is used to purge the porous bed of carbon monoxide formed during the reduction reaction to drive the reduction reaction more rapidly toward complete reduction of the phosphorus pentoxide and to inhibit oxidation of the phosphorus vapor and carbonaceous material within the porous bed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.