Membrane treatment method for semipermeable membranes
US4634531A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1985 |
| Grant date | Jan 6, 1987 |
| Priority date | — |
| Expiry date | Feb 12, 2005 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D67/0088
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention relates to the membrane treatment method for semipermeable membranes, that is, a method wherein it is characterized that not only remarkable improving effect of selective separation performance of semipermeable membranes is obtained but also durability of said improving effect for selective separation performance is improved by means of extremely simple and easy procedures such as said semipermeable membranes are successively brought into contact with very dilute of aqueous solutions including effective substances which are individually water-soluble in due order and for a short time, where said effective water-soluble substances form water-insoluble or very little water-soluble materials thereof fixed on the surface of said semipermeable membranes. The aforesaid remarkable effect is observed especially in the case of semipermeable membranes consisted of cross-linked polymers based of furfuryl alcohol including furfuryl alcohol as an essential monomer component, and polyamides, when, at the same time, the due combination of water-soluble amines and water-soluble aldehyde is employed as said aqueous solutions including effective water-soluble substances.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.