Patent · US Expired

Ion chromatographic method and apparatus using ion reflux

US5914025A · kind A · utility

17Cited by
7References
40Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 9, 1997
Grant dateJun 22, 1999
Priority date
Expiry dateJan 9, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2030/965
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus for generating an acid or base eluent in an aqueous stream solely from an ion exchange bed for liquid chromatography of anions or cations and for simultaneously suppressing conductivity of the eluent in the ion exchange bed after chromatographic separation. For a system in which a base is generated for the analysis of anions by ion chromatography, the method uses a bed of cation exchange material with first and second bed sections arranged in series. For anion analysis, the method includes: PA1 (a) flowing an aqueous feed stream through the first bed section while applying an electrical potential to form an aqueous eluent stream comprising a cation hydroxide base, PA1 (b) flowing a liquid sample stream containing anions to be detected and the eluent through a chromatographic separator portion of said first bed section, to separate said anions to be detected, PA1 (c) flowing said aqueous separated anion stream through said second bed section substantially free of anion exchange material and including exchangeable hydronium ions, while applying an electrical potential to convert said base to weakly ionized form, and displacing some of said exchangeable hydroniu…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.