Calcium-sodium polysulfide chemical reagent and production methods
US7534413B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 14, 2005 |
| Grant date | May 19, 2009 |
| Priority date | — |
| Expiry date | Dec 8, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P70/50
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A calcium-sodium polysulfide chemical reagent and methods for producing the reagent. The reagent is a blend of calcium polysulfide and sodium polysulfide that can be prepared using various types, sources and ratios of lime, elemental sulfur and sulfide ion using either virgin or waste materials. The reagent is amenable to inexpensive and high rate production methods at ambient or warmer temperatures. The reagent can be used to precipitate metals from wastewater, stabilize hexavalent chrome in hazardous waste residues, remove mercury from coal fired power plants, and as an electrolyte in large-scale bromide/polysulfide electrical storage batteries.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.