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US4745134A
Expired / Lapsed
US
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Inert separator beads for regeneration of mixed bed-ion exchange resins
Assignee: Rohm and Haas Co
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Filing: 1984-06-27
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Granted: 1988-05-17
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Expires: 2004-06-27
Abstract
Abstract Improved, inert separator beads for separating cation exchange resins from anion exchange resins during regeneration of mixed-bed exchange resins have been discovered. These beads are crosslinked copolymers of methyl methacrylate, styrene and a hydrophilic monomer containing an amide functionality, and have little tendency to clump together or clump at an air-water interface.
Inventors
- 👤 Peter Osei-Gyimah
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:29
CPC Classifications
B; B01; B01J; B01J47/00; B01J47/02; B01J47/04; C; C08; C08F; C08F220/00; C08F220/02; C08F220/10; C08F220/12; C08F220/14; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
86 words
Improved, inert separator beads for separating anion exchange resin beads from cation exchange resin beads during regeneration of mixed-bed ion exchange resins, which inert separator beads comprise a copolymer of from about 60 to about 90 weight percent methyl methacrylate, from about 5 to about 15 weight percent styrene, from about 2 to about 10 weight percent hydrophilic monomer containing an amide functional group, and from about 1 to about 6 weight percent polyvinyl crosslinking monomer, the percentages based upon the total weight of the copolymer.
Claim 2
Dependent Claim
86 words
Improved, inert separator beads for separating anion exchange resin beads from cation exchange resin beads during regeneration of mixed-bed ion exchange resins, which inert separator beads comprise a copolymer of from about 60 to about 90 weight percent methyl methacrylate, from about 5 to about 15 weight percent styrene, from about 2 to about 10 weight percent hydrophilic monomer containing an amide functional group, and from about 1 to about 6 weight percent polyvinyl crosslinking monomer, the percentages based upon the total weight of the copolymer.
Claim 3
Dependent Claim
42 words
The separator beads of claim 1 wherein the hydrophilic monomer is selected from the group consisting of acrylamide, N-methyl acrylamide, N,N-dimethyl acrylamide, N-ethyl acrylamide, vinyl-pyrolidone, hydroxyalkyl acrylamide where the alkyl group has from 2 to 6 carbon atoms, and the corresponding methacrylamides.
Claim 4
Dependent Claim
12 words
The separator beads of claim 1 wherein the hydrophilic monomer is methacrylamide.
Claim 5
Dependent Claim
27 words
The separator beads of claim 1 wherein the polyvinyl crosslinking monomer is selected from the group consisting of divinylbenzene, trivinylbenzene, ethylene glycol dimethacrylate, trimethylolpropane, trimethacrylate and divinylnaphthalene.
Claim 6
Dependent Claim
13 words
The separator beads of claim 1 wherein the polyvinyl crosslinking monomer is divinylbenzene.
Claim 7
Dependent Claim
23 words
The separator beads of claim 1 wherein the separator beads have a wet density between about 1.15 and about 1.17 g/cm 3 .
Claim 8
Dependent Claim
26 words
The separator beads of claim 1 wherein the separator beads have a particle size range from about 150 μm to about 1 mm in average diameter.
Claim 9
Dependent Claim
20 words
The separator beads of claim 7 wherein the particle size is from about 400 to 800 μm in average diameter.
Claim 10
Dependent Claim
89 words
A mixed-bed ion exchange resin comprising cation exchange resin beads, anion exchange resin beads, and inert separator beads which comprise a copolymer of from about 60 to about 90 weight percent methyl methacrylate, from about 5 to about 15 weight percent stryrene, from about 2 to about 10 weight percent hydrophilic monomer containing an amide functional group, and from about 1 to about 6 weight percent polyvinyl crosslinking monomer, the beads having a hydraulic density between that of the cation exchange resin and that of the anion exchange resin.
Claim 11
Dependent Claim
89 words
A mixed-bed ion exchange resin comprising cation exchange resin beads, anion exchange resin beads, and inert separator beads which comprise a copolymer of from about 60 to about 90 weight percent methyl methacrylate, from about 5 to about 15 weight percent stryrene, from about 2 to about 10 weight percent hydrophilic monomer containing an amide functional group, and from about 1 to about 6 weight percent polyvinyl crosslinking monomer, the beads having a hydraulic density between that of the cation exchange resin and that of the anion exchange resin.
Claim 12
Dependent Claim
25 words
The mixed-bed ion exchange resin of claim 9 wherein from about 10 to about 15 volume percent of the mixed-bed resin is inert separator beads.
Claim 13
Dependent Claim
23 words
The mixed-bed resin of claim 9 wherein the inert separator beads have an average diameter from about 150 μm to about 1 mm.
Claim 14
Dependent Claim
22 words
The mixed-bed resin of claim 9 wherein the inert separator beads have an average diameter from about 400 to about 800 μm.
Claim 15
Dependent Claim
25 words
The mixed-bed resin of claim 9 wherein the wet density of the inert separator beads is from about 1.15 to about 1.17 g/cm 3 .
Claim 16
Dependent Claim
56 words
The separator beads of claim 1 wherein the copolymer is a copolymer of from about 60 about 90 weight percent methylmethacrylate, from about 5 to about 15 weight percent styrene, from about 5 to about 10 weight percent hydrophilic monomer containing amide functional groups, and from about 1 to about 6 weight percent polyvinyl crosslinking monomer.
Claim 17
Dependent Claim
62 words
The mixed-bed ion exchange resin of claim 9 wherein the inert separator beads comprise a copolymer of from about 60 to about 90 weight percent methylmethacrylate, from about 5 to about 15 weight percent styrene, from about 5 to about 10 weight percent hydrophilic monomer containing an amide functional group and from about 1 to about 6 weight percent polyvinyl crosslinking monomer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-05-17 | 1991-11-16 | 1992-05-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-05-17 | 1995-11-16 | 1996-05-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-05-17 | 1999-11-16 | 2000-05-17 | $7700.00 | Window Closed / Lapsed |