PROMISING MULTIFUNCTIONAL ANIONITES FOR THE EXTRACTION OF CHROMIUM (VI) IONS

Abstract

Introduction. 30% of the chromium ore reserves in the world are concentrated in
Kazakhstan, during the processing of which large volumes of wastewater containing toxic chromium salts,
are formed. Сhromium is one of the priority components both in terms of emission and toxicity (for
Cr(VI), the maximum permissible concentration is 0.05 mg/l). The compounds of chromium (III) and
especially chromium (VI) have a general toxic, allergenic, carcinogenic, mutagenic effect on the human
body, and are among the most dangerous pollutants for the environment. The aim of this work is to
develop a technological scheme for the extraction of Cr (VI) ions by multifunctional ion
exchangers. Methods. Anionite, based on diglycidyl ether of dioxyphenylpropane, allylglycidyl ether and
polyethylenimine – Ionite No. 1 has been synthesized by polycondensation, and epoxyamine has been
synthesized from benzylamine and epichlorohydrin, by the condensation of which Ionite No.2 has been
obtained with polyethylenimine. The sorption of chromium ions on newly synthesized anionites has been
studied, using model solutions with the concentrations of 25, 50, 75 and 100 mg/l Cr (VI). Results and
discussion. It has been established that Ionite No.1 exhibits greater affinity for Cr (VI) ions. So, its
maximum sorption capacity is 13.5, and that of Ionite No.2 is 11.7 mg/g. Conclusion. We have proposed a
basic technological scheme of a desalination plant, consisting of modular units: reagent-mechanical,
sorption, membrane, ion exchange and bacterial purification. It has been established that reagentmechanical purification is the initial stage of water treatment, designed to isolate insoluble coarse- and
fine-dispersed impurities.