Method for preparing thin regenerated cellulose membranes of high flux and selectivity for organic liquids separations
US4496456A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 3, 1983 |
| Grant date | Jan 29, 1985 |
| Priority date | — |
| Expiry date | Jun 3, 2003 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D71/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method is described for the production of regenerated cellulose membranes which method comprises the steps of: PA1 (a) dissolving a cellulose material to form a solution; PA1 (b) casting the cellulose solution into a film; PA1 (c) coagulating the cellulose solution film using an alkali alcoholic solution; PA1 (d) washing the coagulated cellulose film in an alcohol; PA1 (e) regenerating the cellulose film using acidic alcohol solution; PA1 (f) washing the regenerated cellulose membrane using an alcohol. The regenerated cellulose thus formed may be dried, if desired, preferably without a softener. The regenerated cellulose thus produced, when prepared in the form of a film or membrane, possesses higher flux and superior selectivity for organic liquid separation than regenerated cellulose membranes prepared employing aqueous solutions in steps b through e above and is most advantageously employed for the recovery of polar dewaxing solvents (e.g. ketones and mixed ketone/aromatic solvents) from dewaxed oil.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.