Simultaneous determination of inorganic disinfection by-products and the seven standard anions by ion chromatography

For the first time, an ion chromatographic method for the simultaneous dete rmination of the disinfection by-products bromate, chlorite, chlorate, and the so-called seven standard anions, fluoride, chloride, nitrite, sulfate, bromide, nitrate and orthophosphate is presented. The separation of the ten anions was carried out using a laboratory-made high-capacity anion-exchang er. The high capacity anion-exchanger allowed the direct injection of large sample volumes without any sample pretreatment, even in the case of hard w ater samples. For quantification of fluoride, chloride, nitrite, sulfate, b romide, nitrate, orthophosphate and chlorate, a conductivity detection meth od was applied after chemical suppression. The post-column reaction, based on chlorpromazine, was optimized for the determination of chlorite and brom ate. The method detection limit for bromate measured in deionized water is 100 ng/l and for chlorite, it is 700 ng/l. In hard drinking water, the meth od's detection limits are 700 ng/l (bromate) and 3.5 mu g/l (chlorite). The method's detection limits for the other eight anions, determined by conduc tivity detection, are between 100 mu g/l (nitrite) and 1.6 mg/l (chlorate). (C) 2000 Elsevier Science B.V. All rights reserved.