Patent US3737044A successfully refreshed from Google Patents.
US3737044A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid treatment system for high ph water
Assignee: Graftech Technology LLC
•
Filing: 1972-04-06
•
Granted: 1973-06-05
•
Expires: 1992-04-06
Abstract
Abstract A packing composition effective to reduce the pH of alkaline liquids, used as a pretreatment, in association with a reverse osmosis membrane and support in a liquid treatment system, is made of an encapsulating matrix of polymeric material that is essentially water impermeable at a pH between about 4.5 and 8 and which becomes significantly water permeable at a pH above about 9, and an acidulous material which is encapsulated by the matrix at a pH between about 4.5 and 8, and released progressively from the matrix at a pH above about 9.
Inventors
- 👤 R Chamberlin
- 👤 R Stana
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 15:13
CPC Classifications
B; B01; B01D; B01D61/00; B01D61/02; B01D61/04; B01D61/025; C; C02; C02F; C02F1/00; C02F1/66; B01D2311/00; B01D2311/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
55 words
A packing composition effective to reduce the pH of alkaline liquids comprising: a. a matrix of polymeric material that is essentially water impermeable at a pH between about 4.5 and 8 and which becomes substantially water permeable at a pH above about 9, and b. an acidulous material distributed throughout and encapsulated by the matrix.
Claim 2
Dependent Claim
28 words
The composition of claim 2 wherein the acidulous material is uniformly distributed throughout the matrix and constitutes from about 1 to 60 weight percent of the packing composition.
Claim 3
Dependent Claim
54 words
The composition of claim 3 wherein the acidulous material is selected from the group consisting of alumina, magnesium nitrate, magnesium chloride, magnesium sulfate, ammonium nitrate, ammonium chloride, ammonium sulfate, silver nitrate, silver chloride, silver sulfate, lead nitrate, lead chloride, lead sulfate, iron nitrate, iron chloride, iron sulfate, aluminum nitrate, aluminum chloride and aluminum sulfate.
Claim 4
Dependent Claim
33 words
The composition of claim 3 wherein the polymeric material constituting the matrix comprises a cellulose compound containing a chemical group which is appreciably hydrolyzable in water at a pH greater than about 9.
Claim 5
Dependent Claim
34 words
The composition of claim 5 wherein the polymeric material constituting the matrix is selected from the group consisting of cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate-butyrate, cellulose acetate-propionate, methyl cellulose and ethyl cellulose.
Claim 6
Dependent Claim
21 words
The composition of claim 5 wherein the acidulous material is alumina and the polymeric material constituting the matrix is cellulose acetate.
Claim 7
Independent Claim
75 words
A method of making a packing composition useful in reducing the pH of alkaline liquids comprising (1) admixing a liquid comprising a polymeric material that is essentially water impermeable at a pH between about 4.5 and 8 and which becomes substantially water permeable at a pH above about 9, and 1 to 60 weight percent of a particulate acidulous material and (2) congealing said liquid admixture to form a polymeric matrix encapsulating said acidulous material.
Claim 8
Dependent Claim
26 words
The method of claim 8 wherein the admixture is a hot liquid, said hot liquid being extruded through a shaped opening, and thereafter congealed by cooling.
Claim 9
Dependent Claim
43 words
The method of claim 8 wherein the admixture also contains a leachable solvent, a leachable swelling agent and the admixture is congealed by leaching the admixture to form a matrix of polymeric material with acidulous material distributed throughout and encapsulated by the matrix.
Claim 10
Dependent Claim
48 words
The method of claim 10 wherein the acidulous material is alumina having a particle size range from about 0.002 to 297 microns and the polymeric material is selected from the group consisting of cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate-butyrate, cellulose acetate-propionate, methyl cellulose and ethyl cellulose.
References Cited (Backward Citations)
US2528847A
Cited
US2955067A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-04 | 1976-12-04 | 1977-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-04 | 1980-12-04 | 1981-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-04 | 1984-12-04 | 1985-06-05 | $7700.00 | Window Closed / Lapsed |