Additives for salt rejection enhancement of a membrane
US9861940B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 2015 |
| Grant date | Jan 9, 2018 |
| Priority date | — |
| Expiry date | Feb 22, 2036 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2325/20
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Provided is an interfacial polymerization process for preparation of a thin film composite membrane, which can be used for nanofiltration, forward osmosis, or reverse osmosis, particularly for use with brackish water or seawater. The process includes contacting a porous support membrane with an aqueous phase containing a polyamine to form a coated support membrane, and applying an organic phase containing a polyfunctional acyl halide to the coated support membrane to interfacially polymerize the polyamine and the polyfunctional acyl halide to form a discrimination layer of a thin film composite membrane, where during formation of the membrane, the polyfunctional acyl halide is purified in situ by removal of hydrolyzed acyl halide through addition of a salt rejection-enhancing additive that includes a biguanide compound, dicarbonate compound, pentathiodicarbonate compound, or salt thereof. Also provided are the membranes prepared by the methods and reverse osmosis modules containing the membranes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.