Ion Chromatography in Water Analysis: Application in Analysis of Anions in Water and Waste Water

摘要

Since the 1980's, Ion Chromatography was developed into a powerful and sensitive tool for Ion Analysis. Nowadays, anionand cation-chromatography is a well-established technique and used for the determination of a large number of ions in different matrices. As the presentation of an overview of the wide field of Ion Chromatography (IC) is clearly beyond the scope of this short paper, the book of Joachim Weiss [1] is strongly recommended. This paper focuses on the analysis of anions in water and waste water and aims to motivate to use this technique. Since ion chromatography found its way into water laboratories the routine analysis of nitrate and sulfate presented one of the major problems in water analysis. The determination of nitrate in water by photometric analysis required the use of high concentrated sulfuric acid to nitrify an aromatic compound. The analysis of sulfate was time consuming and labor intensive. Instead, ion chromatography was a fast and easy method to determine nitrate and sulfate in a large number of samples. Thus, the determination of fluoride, chloride, nitrate and sulfate by ion chromatography was the first well established IC method in water analysis. The anions were detected by conductivity. In some cases UV-detection and inverse UV-detection were used. The suppressor systems, necessary for sensitive measurements using conductivity detection, were improving. Nowadays the measurement of concentrations in ppb-range is possible. Furthermore, the separation columns for anion determination are much more efficient in comparison to the beginnings of ion chromatography; a wide offer of different columns allows to solve nearly all separation problems in routine analysis.