Method and apparatus for the quantitative determination of cations or anions by ion chromatography

摘要

A method and a device for the quantitative determination of cations and anions by ion chromatography is described, which e.g. can be used to examine drinking water, river water or waste water. The sample is injected into a buffer solution and passed together with it through a chromatography column. The eluate emerging there is subjected to background desalination and then to a conductivity measurement. In order to achieve more uniform chemical working conditions, it is proposed for background desalination to pass the eluate of the chromatography column between two ion exchange foils (10, 12), which are impermeable to the ions to be determined, apart from two electrodes (14 , 16) to be arranged, which generate an electrical field penetrating the eluate channel (18), and to pass solutions of strongly dissociated electrolytes between the electrodes (14, 16) and the foils (10, 12) with which the ions of the buffer substances remaining in the eluate are converted into compounds of lower conductivity and the oppositely charged ions of the buffer substances are continued.