EP0146655A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A process for separating mixtures of water and an organic compoundand a water-selective permeation membrane
Assignee: Dow Chemical Co
•
Filing: 1983-12-14
•
Granted: —
•
Expires: 2003-12-14
Abstract
Abstract A water-selective permeation membrane and a process for the separation of water from water-miscible organic compounds, comprising contacting a mixture of water and an organic compound against one side of a membrane comprising a salt of an anionic polysaccharide (e.g. an anionic cellulose derivative) or blends thereof with a polyanion which is not a polysaccharide, and withdrawing at the other side of said membrane a mixture having a higher concentration of water.
Inventors
- 👤 Charles Everett Reineke
- 👤 James Anthony Jagodzinski
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 05:45
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/36; B01D71/00; B01D71/06; B01D71/08; B01D71/12; B01D71/20; B01D71/22; B01D71/40; B01D71/401
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
51 words
A water-selective permeation membrane comprising a salt of a polysaccharide or polysaccharide derivative having a plurality of anionic groups derived from a strong or weak acid, said anionic groups being present in an amount sufficient to allow the membrane to permeate water while substantially impeding the permeation of organic compounds therethrough.
Claim 2
Dependent Claim
51 words
A water-selective permeation membrane comprising a salt of a polysaccharide or polysaccharide derivative having a plurality of anionic groups derived from a strong or weak acid, said anionic groups being present in an amount sufficient to allow the membrane to permeate water while substantially impeding the permeation of organic compounds therethrough.
Claim 3
Dependent Claim
23 words
The membrane of Claim 1 wherein the polysaccharide or polysaccharide derivative is alginic acid, carboxylkycellulose cellulose sulfate, cellulose phosphate, carboxyalkylalkylcellulose or sulfo- alkylcellulose.
Claim 4
Dependent Claim
20 words
The membrane of Claim 1 wherein the polysaccharide or polysaccharide derivative contains a plurality of sulfate, sulfonate or carboxylate groups.
Claim 5
Dependent Claim
27 words
The membrane of Claim 2 wherein said polysaccharide derivative is a cellulose derivative containing from 0.1 to 3.0 anionic groups per anhydroglucose unit of the cellulose molecule.
Claim 6
Dependent Claim
11 words
The membrane of Claim 4 wherein the cellulose derivative is carboxymethylcellulose.
Claim 7
Dependent Claim
42 words
The membrane of Claim 1 further comprising a salt of a polymer which is not a polysaccharide having a plurality of anionic groups derived from a strong or weak acid in an amount sufficient to increase the charge density on said membrane.
Claim 8
Dependent Claim
25 words
The membrane of Claim 6 wherein the polymer which is not a polysaccharide is a polymer of acrylic acid, vinylsulfonic acid or styrene sulfonic acid.
Claim 9
Dependent Claim
22 words
The membrane of Claim 1 or 6 wherein said salt of the polysaccharide or polysaccharide derivative is an alkali metal salt thereof.
Claim 10
Dependent Claim
14 words
The membrane of Claim 8 wherein the alkali metal salt is a cesium salt.
Claim 11
Dependent Claim
21 words
The membrane of Claim 6 wherein the polymer which is not,apolysaccharide comprises from 1 to 70 weight percent of said membrane.
Claim 12
Dependent Claim
21 words
The membrane of Claim 1 or 6 which is crosslinked in an amount sufficient to render the membrane insoluble in water.
Claim 13
Dependent Claim
78 words
A process for separating mixtures of water and an organic compound comprising (a) contacting one side of a membrane comprising a salt of a polysaccharide or polysaccharide derivative having a plurality of anionic groups derived from a strong or weak acid with a.fluid feed mixture containing water and an organic compound, and (b) withdrawing from the other side of said membrane a permeate in vapor form, said permeate containing a higher concentrate of water than said feed mixture.
Claim 14
Dependent Claim
78 words
A process for separating mixtures of water and an organic compound comprising (a) contacting one side of a membrane comprising a salt of a polysaccharide or polysaccharide derivative having a plurality of anionic groups derived from a strong or weak acid with a.fluid feed mixture containing water and an organic compound, and (b) withdrawing from the other side of said membrane a permeate in vapor form, said permeate containing a higher concentrate of water than said feed mixture.
Claim 15
Dependent Claim
13 words
The process of Claim 12 wherein said polysaccharide derivative is a cellulose derivative.
Claim 16
Dependent Claim
16 words
The process of Claim 13 wherein said cellulose derivative is carboxymethyl cellulose, cellu--lose sulfate, or sulfoethylcellulose.
Claim 17
Dependent Claim
33 words
The process of Claim 12 wherein said membrane further comprises a salt of a polymer which is not a polysaccharide having a plurality of anionic groups derived from a strong or weak acid.
Claim 18
Dependent Claim
17 words
The process of Claim 12 or 15 wherein the membrane is rendered insoluble in water by crosslinking.
Claim 19
Dependent Claim
15 words
The process of Claim 12 or 15 wherein the organic compound is an aliphatic alcohol.
Claim 20
Dependent Claim
11 words
The process of Claim 17 wherein the aliphatic alcohol is ethanol.
Claim 21
Dependent Claim
17 words
The process of Claim 12 or 15 wherein the permeate comprises at least 95 weight percent water.
Claim 22
Dependent Claim
15 words
The process of Claim 19 wherein the permeate comprises at least 98 weight percent water.
Claim 23
Dependent Claim
12 words
The process of Claim 12 wherein the counterion is an alkali metal.
Claim 24
Dependent Claim
10 words
The process of Claim 21 wherein the counterion is cesium.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.