Patent · US Expired

Combination apparatus and method for chromatographic separation and quantitative analysis of multiple ionic species

US4314823A · kind A · utility

109Cited by
10References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 13, 1979
Grant dateFeb 9, 1982
Priority date
Expiry dateSep 13, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T436/25375
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Apparatus and method for chromatographic separation and quantitation of different ions of like charges in a sample, e.g., cations or anions. Referring to anion separation, the sample is directed to a first chromatographic column of the ion exclusion type in which the weak acids (e.g., carboxylic acids) and their salts are partially or totally resolved and separated from a fraction of strong acids (e.g., mineral acids) due to Donnan exclusion. The resolved weak acids may be passed directly to a conductivity cell for quantitative detection. The strong acids may be directed to anion exchange bed with a highly ionized developing reagent and eluted in resolved form with the effluent being passed to a suppressor ion exchange bed wherein the developing reagent is converted to a weakly ionized form without destroying the anion separation. Then, a fraction of the strong acids is detected with the same or a different conductivity cell. Prior to separation, the strong acids are preferably directed through a concentrator column formed of ion exchange resin in which they are retained but not resolved while the remaining solution is removed. Thereafter, the developing agent used for separation o…

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