Lataeva A. Sorption-atomic-absorption determination of heavy metals in natural waters with high mineralization

The work is devoted to the development of effective methods of sorption preconcentration using silica gel, chemically modified by N-allyl-N'-propylthiourea and mercaptopropyl groups, and to the determination of trace amounts of heavy metals in surface and ground waters. The influence of macrocomponent composition of mineral water on the direct electrothermal atomic-absorption determination of copper, lead, cadmium and vanadium ions, using the model solutions and natural mineral waters of different salinity, has been researched, maximum permissible salts concentrations were established. It is proved, that the presence of sulfate, chloride, bicarbonate ions in mineral waters significantly affects the analytical signals, which distorts the results of the direct electrothermal atomic-absorption determination of trace amounts of lead, cadmium and vanadium. A method of the sorption-atomic-absorption determination of these metals has been suggested, the optimum conditions of their sorption were established. The sorption-atomic-absorption method for determination of heavy metals in the real objects with a hight salinity using an internal standard to control the measurement error has been first developed. Metrological characteristics of the techniques of direct electrothermal atomic-absorption determination of copper and zinc, and sorption-atomic-absorption determination of lead, cadmium and vanadium ions in the highly mineralized waters with preconcentration on the silica gels, chemically modified by N-allyl-N'-propylthiourea and mercaptopropyl groups, have been studied