Composite polyamide reverse osmosis membrane and method of producing the same
US6245234A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 1999 |
| Grant date | Jun 12, 2001 |
| Priority date | — |
| Expiry date | Jun 3, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D69/125
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A composite polyamide reverse osmosis membrane and method of producing same. In one embodiment, the membrane is made by coating a porous polysulfone support for about 40 seconds with an aqueous solution containing (i) a polyfunctional primary or secondary amine in the form of 1.6 wt. % of meta-phenylenediamine (MPD), (ii) a polyfunctional tertiary amine in the form of 0.4 wt. % N,N,N',N'-tetramethyl-1,6-hexanediamine (TMHD), and (iii) a polar solvent in the form of 0.2 wt. % 2-ethyl-1,3-hexanediol (EHD). Next, the excess aqueous solution is removed, and the coated support is dipped for about 1 minute in a 0.1 wt. % organic solvent solution of trimesoyl chloride (TMC) in a mixture of alkanes having from 8 to 12 carbon atoms. After draining the organic solvent solution off, the resulting composite membrane is air dried at room temperature for about 1 minute and then rinsed in a 0.2% Na.sub.2 CO.sub.3 aqueous solution for 30 minutes at room temperature. The resultant membrane exhibits a flux of 46.5 gfd and a salt rejection of 97.1% when used at 225 psi for an aqueous solution containing 2000 ppm of NaCl. In another embodiment, instead of including a polyfunctional tertiary amine in t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.