Dual ion chromatograph using parallel columns for ionic analysis

摘要

Integrated system for the concurrent quantitative analysis, using ion exchange resin, of chromatographically separable cations and anions contained in a single measured portion of aqueous sample solution includes an eluant water reservoir, a sample injection valve, a pump delivering water from the reservoir to the sample injection valve, and thence to a first stream splitter feeding two parallel ion exchange columns. One column is charged with anion exchange resin and the other with cation exchange resin, preferably with differing bed depths but in any event selected in nature and geometry to achieve differing elution times for each ion present and being determined, and ordinarily to achieve elution of all the ions of one sign before elution of the ions of the opposite sign, e.g., all the anions before the cations. The effluent from each column is joined through a second stream splitter and the resulting single stream is directed to a conductivity cell with associated readout means. The effluent from the conductivity cell may be discarded but is ordinarily passed through clean-up resin bed means and cycled back to the eluant water reservoir. Preferably means are provided for (1) substituting columns with different resins and bed depths for specific analyses, (2) occasionally flushing the sample solution delivery system with bactericide, or (3) running known standard solution.