Flocculation of coal fines with polyelectrolytes and electrolyte
US4906386A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 3, 1988 |
| Grant date | Mar 6, 1990 |
| Priority date | — |
| Expiry date | Nov 3, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F1/54
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
Coal fines are flocculated from an aqueous suspension by adding an anionic polyelectrolyte, a soluble calcium salt, and a cationic polyelectrolyte to the suspension. The anionic polyelectrolyte is preferably a high charge density, high molecular weight acrylic acid/acrylamide copolymer or a high charge density high molecular weight terpolymer of acrylic acid/methacrylic acid/ethylacrylate. The cationic polyelectrolyte is preferably a high molecular weight, low charge density dimethylamino methylmethacrylate methyl chloride quaternary ammonium salt/acrylamide copolymer, an N,N dimethyl 2 hydroxy propyl imine homopolymer or low molecular weight, a diallyl dimethyl ammonium chloride polymer, or ter polyepichlorohydrin dimethyl amine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.