Phosphorus pentasulfide waste water treatment
US4301014A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1980 |
| Grant date | Nov 17, 1981 |
| Priority date | — |
| Expiry date | Jun 5, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/906
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The process disclosed in this invention takes the waste solids, gases, and water from a phosphorus pentasulfide manufacturing facility and hydrolyzes the phosphorus pentasulfide by heating. The phosphorus portion is converted to a soluble phosphate and the sulfur portion to a mixture of sulfide, sulfite and sulfate. The soluble fraction is then treated with a calcium hydroxide solution precipitating the phosphate and sulfates which are removed. The gaseous portion of the hydrolysis is fed to a catalytic oxidizer which converts the sulfides to sulfur, which is removed and the gas, free of sulfur containing species, is exhausted to the atmosphere. The filtrate from the precipitation reaction can be recycled to the plant, or may be chlorinated and discharged.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.