Novel water softening process using membranes
US4824574A · kind A · utility
29Cited by
13References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 13, 1988 |
| Grant date | Apr 25, 1989 |
| Priority date | — |
| Expiry date | Jun 13, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2323/30
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A novel water softening membrane and process for making the same is described. The membrane can be prepared by treating a polyamide reverse osmosis membrane with a strong mineral acid followed by treatment with a rejection enhancing agent. The resulting membrane at transmembrane pressures of 50 psi can attain a magnesium sulfate rejection with a 0.2 percent aqueous solution of more than 90 percent with a water flux of more than 15 gallons per square foot per day.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.