Error analysis of the determination of anions in water by ion chromatography

Error analysis of ion chromatography for the determination of anions in water is as follows:

Chloride ions and sulfate ions are high. This type of problem is mainly staff in the test process, the application of experimental water and standard requirements do not match, in fact, this type of experimental water needs to meet the production of pure water apparatus under a constant 18.2MΩ * cm, the flow of 2min after the pure water, only so that all the chlorine ions in the water and sulfate ions can be removed cleanly.

Ion Chromatography (Ion Chromatography) is a type of High Performance Liquid Chromatography (HPLC), which is a liquid chromatographic method for analyzing anions and cations.

Narrowly speaking, Ion Chromatography is a chromatographic method that separates ionic substances by using ion exchange resin with low exchange capacity as a stationary phase, and continuously detects the change of conductivity of the effluent with a conductivity detector. Ion chromatography is defined in Principles and Applications of Ion Chromatography as a liquid chromatographic method that uses the ionic nature of the substance to be measured for separation and detection.

Development history:

In 1975, Small et al. successfully solved the problem of continuous detection of column effluent with a conductivity detector, i.e., the use of an anion- or cation-exchange column of low exchange capacity, the separation of inorganic ions with a strong electrolyte as the mobile phase, the effluent passes through a column called inhibition column and the separation of the packing of the column with the opposite charge. The effluent passes through a column of ion exchange resin called suppressor column which has the opposite charge to the packing material of the separation column.

In this way, the counter ion of the measured ion in the mobile phase is removed, and the background conductance of the mobile phase is reduced, thus obtaining high detection sensitivity. From then on, there is a real sense of ion chromatography (ion chromat ography, IC), IC also from then on as a chromatographic separation technology from the liquid chromatography independent.

In 1979, Gjerde et al. used weak electrolyte as mobile phase. Because of the low conductivity of the mobile phase itself, it could be detected directly by a conductivity detector without using a suppressor column.

People call the ion chromatography using a suppressor column double column ion chromatography (double column IC) or suppressed ion chromatography (suppressed IC), and the ion chromatography without a suppressor column single column ion chromatography (single column IC) or non-suppressed IC (non-suppressed IC). The method of ion chromatography without the use of a suppressor column is called single column ion chromatography (s ingle column IC) or non-suppressed IC.