Method of manufacturing a reverse osmosis membrane and the membrane so produced
US4894159A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1989 |
| Grant date | Jan 16, 1990 |
| Priority date | — |
| Expiry date | Jun 5, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D71/68
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Reverse osmosis membranes are manufactured by casting a polysulfone casting composition comprising: PA1 (i) an aromatic polysulfone derivative having repeat units, at least an average of about 20% of which are carboxylated and are of the formula I: ##STR1## , wherein each R in each formula is ortho to the sulfone, at least one R in each formula is a carboxyl group with any remainder thereof being hydrogen, and PA1 (ii) a solvent for the aromatic polysulfone derivative, then evaporating solvent from the casting composition and then gelling the casting composition into a reverse osmosis membrane. The permeability of the reverse osmosis membrane may be increased by the addition of a non-solvent for the aromatic polysulfone derivative to the casting composition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.