US3857777A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ion exchange membrane for measuring orthophosphate
Assignee: Environmental Protection Agency
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Filing: 1973-08-10
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Granted: 1974-12-31
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Expires: 1993-08-10
Abstract
Abstract A new ion exchange membrane with a mixed complex employing a ligand with a thiourea functional group, is used to give an electrode specificity in monitoring the concentration of a specific solute species. Specificity is achieved by measuring changes in another ligand''s exchanging rates, which varies preferentially with the concentration of the solute species being studied. An electrode using a new combination, a silver polythioureaglutaraldehyde phosphate complex mixed with silver sulfide has been built and used to attain electrode specificity in measuring orthophosphate ions.
Inventors
- 👤 G Guilbault
- 👤 F Shu
- 👤 Storp H Von
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 07:55
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/28; G01N27/30; G01N27/333; G01N27/3335
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
99 words
AN ION EXCHANGE MEMBRANE TO SEGREGATE A REFERENCE ELCTRODE FROM A FLUID SAMPLE, WHICH BOTH THE SEGREGATED REFERENCE ELECTRODE AND A MEASURING ELCTRODE ARE SUSPENDED IN A FLUID SAMPLE THAT CONTAINS A SPECIFIC ION FROM A CLASS OF LARGE MOLECULE ANIONS, RESULTS IN A POTENTIOMETRIC VALUE FOR SAID MEASURING ELECTRODE AND FLUID SAMPLE WHEN MEASURED AGAINST SAID REFERENCE ELECTRODE, AND WHEREIN THE POTENTIOMETRIC VALUE VARIES PREDOMINANTLY WITH THE VARIATION IN CONCENTRATION OF SAID SPECIFIC ION RATHER THAN WITH THE VARIATION OF CONCENTRATION OF OTHER SOLUTE SPECIES, WHEREIN SAID MEMBRANE COMPRISES, A THOIOUREA-ALDEHYDE POLYMER, SILVER ION AND A PHOSPHATE ION.
Claim 2
Dependent Claim
99 words
AN ION EXCHANGE MEMBRANE TO SEGREGATE A REFERENCE ELCTRODE FROM A FLUID SAMPLE, WHICH BOTH THE SEGREGATED REFERENCE ELECTRODE AND A MEASURING ELCTRODE ARE SUSPENDED IN A FLUID SAMPLE THAT CONTAINS A SPECIFIC ION FROM A CLASS OF LARGE MOLECULE ANIONS, RESULTS IN A POTENTIOMETRIC VALUE FOR SAID MEASURING ELECTRODE AND FLUID SAMPLE WHEN MEASURED AGAINST SAID REFERENCE ELECTRODE, AND WHEREIN THE POTENTIOMETRIC VALUE VARIES PREDOMINANTLY WITH THE VARIATION IN CONCENTRATION OF SAID SPECIFIC ION RATHER THAN WITH THE VARIATION OF CONCENTRATION OF OTHER SOLUTE SPECIES, WHEREIN SAID MEMBRANE COMPRISES, A THOIOUREA-ALDEHYDE POLYMER, SILVER ION AND A PHOSPHATE ION.
Claim 3
Dependent Claim
16 words
The ion exchange membrane as defined in claim 1, wherein the thiourea is polymerized with glutaraldehyde.
Claim 4
Dependent Claim
23 words
The ion exchange membrane as defined in claim 1, wherein the ligand that is a large molecule anion, is the dibasic phosphate ion.
Claim 5
Dependent Claim
120 words
An ion exchange membrane to segregate a reference electrode from a fluid sample, which when both the segregated reference electrode and a measuring electrode are suspended in a fluid sample that contains a specific ion from a class of large molecule anions, results in a potentiometric value for said measuring electrode and fluid sample when measured against said reference electrode, and wherein the potentiometric value varies predominantly with the variation in concentration of said specific ion rather than with the variation of concentration of other solute species, wherein said membrane comprises, a mixed complex, and said mixed complex comprises, a ligand made by polymerizing thiourea with glutaraldehyde, and another ligand that is a dibasic phosphate ion, and a silver ion.
Claim 6
Dependent Claim
120 words
An ion exchange membrane to segregate a reference electrode from a fluid sample, which when both the segregated reference electrode and a measuring electrode are suspended in a fluid sample that contains a specific ion from a class of large molecule anions, results in a potentiometric value for said measuring electrode and fluid sample when measured against said reference electrode, and wherein the potentiometric value varies predominantly with the variation in concentration of said specific ion rather than with the variation of concentration of other solute species, wherein said membrane comprises, a mixed complex, and said mixed complex comprises, a ligand made by polymerizing thiourea with glutaraldehyde, and another ligand that is a dibasic phosphate ion, and a silver ion.
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) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |