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US3918906A Expired / Lapsed US ⏱️ 0.0 years remaining

Determining total ionic content

Assignee: Dow Chemical Co
•
Filing: 1973-08-06
•
Granted: 1975-11-11
•
Expires: 1993-08-06
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Abstract

Abstract Method of determining total ionic content of an aqueous sample solution by an ion exchange procedure in which all of the cationic species present are converted to an easily eluted alkali metal cation in a first ion exchange resin bed means after which the anions in the aqueous sample are all exchanged in an anion exchange resin bed means for an easily eluted anion, such as hydroxide or acetate, thereby exchanging all ion species in the sample solution for a single predetermined ion pair and thereafter determining the ion concentration of such ion pair utilizing responsive detector means such as a conductivity cell having associated readout means. The apparatus includes two ion exchange columns and a detector such as a conductivity cell connected in series by liquid conduit means, means for adding liquid sample solution and water as eluant to the first column and readout means associated with the conductivity cell. The apparatus is made ready for use by charging the first column with cation exchange resin in the sodium or lithium form or other easily elutable cation, while the second column is charged with an anion exchange resin in the hydroxide or acetate, other easily elutable anion, forms.

Inventors

  • 👤 Hamish Small
  • 👤 Timothy S Stevens

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 09:35
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/26; G01N30/38; G01N30/46; G01N30/461; B; B01; B01J; B01J39/00; B01J39/04; B01J39/05; B01J39/26; B01J41/00; B01J41/04; B01J41/05; B01J41/20; G01N30/96; B01J2220/00; B01J2220/50; B01J2220/54; G01N2030/965

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 259 words
THE METHOD OF DETERMINING TOTAL IONIC CONTENT IN AN AQUEOUS SOLTION BY QUANTITATIVE ANALYIS OF A PLURALITY OF IONICALLY DISSCOCIATED COMPOUNDS IN THE AQUEOUS AMPLE SOLUTION UTILIZING ION EXHANGE PROCEDURES, WHICH COMPRISES: ADDING APREDETERMINED AMOUNT OF SAID SAMPLE SOLUTION TO A CATION EXCHANGE RESIN BED MEANS, SAID RESIN BED MEANS BEING CHARGED WITH A CATION EXCHANGE RESIN IN EASILY ELUTABLE CATION FORM CAPABLE OF EXCHANGING WITH THE CATIONS OF THE SAMPLE AND DELIVERING ONLY ONE SPECIES OF CATION ON ELUTION, ELUTING FROM SAID RESIN BED MEANS WITH WATR A CONGREGATED QUANTITY OF SAID EASILY ELUTABLE CATIONS CORRESPONDING EQUIVALENT PER EQUIVALENT TO THE NUMBER OF EUIVALENTS OF ION MATERIAL DISSOLVED IN THE SAID PREDETERMINED AMOUNT OF SAMPLE SOLUTION, PASSING THE EFFLUENT FROM THE CATION EXCHANGE RESIN BED MEANS THROUGH AN ANION EXCHANGE RESIN BED MEANS, SAID LATTER RESIN BED MEANS BEING IN EASILY ELUTABLE ANION FORM CAPABLE OF EXCHANGING WITH THE ANIONS OF THE SAMPLE AND DELIVERING ONLY ONE SPECIES OF ANION ON ELUTION THEREBY EXCHANGING ALL ANIONIC SPECIES IN SAID EFFLUENT FOR SUCH EASILY ELUTABLE IONS, THE TOTAL EXCHANGE CAPACITY OF THE CATION AND ANION EXCHANGE RESINS BEING SUFFICIENT TO AT LEAST FREE, BY ION EXCHANGE, A NUMBER OF EQUIVALENT OF EACH OF THE EASILY ELUTABLE CATIONS AND ANION CORRESPONDING TO THE SAID NUMBER OF EQUIVALENTS OF IONICALLY DISSOCIATED COMPOUNDS IN THE PREDETERMINED AMOUNT OF SAMPLE SOLUTION, AND PASSING THE EFFLUENT FROM THE ANION XCHANGE RESIN BED MEANS THROUGH A CONDUCTIVITY CELL HAVING ASSOCIATED READOUT MEANS AND THEREBY QUANTITATIVELY MEASURING THE CONGREGATED QUANTITY OF EASILY ELUTABLE CATIONS AND ANIONS.
Claim 2
Independent Claim 259 words
THE METHOD OF DETERMINING TOTAL IONIC CONTENT IN AN AQUEOUS SOLTION BY QUANTITATIVE ANALYIS OF A PLURALITY OF IONICALLY DISSCOCIATED COMPOUNDS IN THE AQUEOUS AMPLE SOLUTION UTILIZING ION EXHANGE PROCEDURES, WHICH COMPRISES: ADDING APREDETERMINED AMOUNT OF SAID SAMPLE SOLUTION TO A CATION EXCHANGE RESIN BED MEANS, SAID RESIN BED MEANS BEING CHARGED WITH A CATION EXCHANGE RESIN IN EASILY ELUTABLE CATION FORM CAPABLE OF EXCHANGING WITH THE CATIONS OF THE SAMPLE AND DELIVERING ONLY ONE SPECIES OF CATION ON ELUTION, ELUTING FROM SAID RESIN BED MEANS WITH WATR A CONGREGATED QUANTITY OF SAID EASILY ELUTABLE CATIONS CORRESPONDING EQUIVALENT PER EQUIVALENT TO THE NUMBER OF EUIVALENTS OF ION MATERIAL DISSOLVED IN THE SAID PREDETERMINED AMOUNT OF SAMPLE SOLUTION, PASSING THE EFFLUENT FROM THE CATION EXCHANGE RESIN BED MEANS THROUGH AN ANION EXCHANGE RESIN BED MEANS, SAID LATTER RESIN BED MEANS BEING IN EASILY ELUTABLE ANION FORM CAPABLE OF EXCHANGING WITH THE ANIONS OF THE SAMPLE AND DELIVERING ONLY ONE SPECIES OF ANION ON ELUTION THEREBY EXCHANGING ALL ANIONIC SPECIES IN SAID EFFLUENT FOR SUCH EASILY ELUTABLE IONS, THE TOTAL EXCHANGE CAPACITY OF THE CATION AND ANION EXCHANGE RESINS BEING SUFFICIENT TO AT LEAST FREE, BY ION EXCHANGE, A NUMBER OF EQUIVALENT OF EACH OF THE EASILY ELUTABLE CATIONS AND ANION CORRESPONDING TO THE SAID NUMBER OF EQUIVALENTS OF IONICALLY DISSOCIATED COMPOUNDS IN THE PREDETERMINED AMOUNT OF SAMPLE SOLUTION, AND PASSING THE EFFLUENT FROM THE ANION XCHANGE RESIN BED MEANS THROUGH A CONDUCTIVITY CELL HAVING ASSOCIATED READOUT MEANS AND THEREBY QUANTITATIVELY MEASURING THE CONGREGATED QUANTITY OF EASILY ELUTABLE CATIONS AND ANIONS.
Claim 3
Dependent Claim 38 words
The method as in claim 1 wherein the cation exchange resin and the anion exchange resin are each employed in a quantity sufficient to exchange the total ionic content of at least five predetermined amounts of sample solution.
Claim 4
Dependent Claim 38 words
The method as in claIm 1 wherein the cation exchange resin and the anion exchange resin are each employed in a quantity sufficient to exchange the total ionic content of at least 1000 predetermined amounts of sample solution.
Claim 5
Dependent Claim 36 words
The method as in claim 1 wherein the cation exchange resin is in one of the Na and the Li form while the anion exchange resin is in one of the OH and the CH3COO form.

References Cited (Backward Citations)

US2617766A Cited
US2950176A Cited
US3382034A Cited
US3495943A Cited
US3676106A Cited
US3694369A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-11-10 1979-05-12 1979-11-11 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-11-10 1983-05-12 1983-11-11 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-11-10 1987-05-12 1987-11-11 $7700.00 Window Closed / Lapsed

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