Ионохроматографическое определение перхлоратов в питьевой воде с предварительным микроэкстракционным концентрированием

Abstract

PURPOSE OF THE ARTICLE. Ion chromatography method with microextraction preconcentration and conductometric detection basis of domestic equipment and common reagents for determination of perchlorate ions low concentrations in different water samples was developed. METHODOLOGY. Reducing the influence of drinking water matrix components on the analytical signal was achieved by microextraction preconcentration perchlorate-ions using selective ion-pair reagent - tetraethylammonium chloride. The proposed methodological approach does not require a costly mass-spectrometric method, application of high-performance commercial columns and special cartridges. SCIENTIFIC PURPOSE. Different nature sorbents, including volume-porous anionite «Oka-1» were studied. Decreasing perchlorate-ions retention time to 12-13 minutes was estimated using «Oka-1» sorbent. The method of liquid-phase microextraction perchlorates concentration was developed. Concentrate was injected into the flow of amino acid eluent. RESULTS. The detection limit (3s- criterion) was 5∙10 −4 mg/l. Perchlorate-ions were determined in the concentrations range of was 2∙10 −3 - 2∙10 −1 mg/l. Relative error was not exceed 20%. The content of matrix ions Cl − , SO 4 2− , HCO 3− up to 5 g/l was not interfere perchlorate-ions determination. Recommended method had been successfully tested in the determination of perchlorate-ions in different water samples and calcium hypochlorite disinfecting solutions. CONCLUSIONS. Microextraction concentration of perchlorate ions from aqueous solvents using drip extraction method can improve the selectivity determination of perchlorate-ions low concentrations by ion chromatography in isocratic elution with conductometric detection. Recommended simple and accessible method allows to determine perchlorate-ions in different water samples. Keywords: perchlorates, ion chromatography, determination, microextraction concentration. (Russian) DOI: http://dx.doi.org/10.15826/analitika.2014.18.1.008 P.N. Kulikov, E.V. Nayanova, E.V. Elipasheva, G.M. Sergeev Lobachevsky State University, Nizhny Novgorod, Russian Federation