Method of water treatment using polyacrylamide-phosphonate flocculants
US5393436A · kind A · utility
11Cited by
19References
12Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jun 6, 1994 |
| Grant date | Feb 28, 1995 |
| Priority date | — |
| Expiry date | Jun 6, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S210/928
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A method of treating an aqueous system is disclosed. The method may be used to treat sewage streams as well as aqueous streams in pulp and paper mill processing. The method includes the steps of adding a polymeric composition to an aqueous stream. The composition is an anionically modified acrylamide polymer in an aqueous medium. The polymer is formed by reacting an acrylamide polymer with phosphorous acid, and has at least 5 mole percent phosphonate groups based on the acrylamide content of the polymer, and has a molecular weight of at least about 40,000. the pH of the composition is adjusted to at least about 7.7.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.