Dmitry Mendeleev University of Chemical Technology of Russia, Moscow, Russia:

E. N. Kuzin, Associate Professor, Industrial Ecology Department, Candidate of Engineering Sciences, e-mail: e.n.kuzin@mail.ru
Yu. M. Averina, Associate Professor, Department of Innovative Materials and Corrosion Protection, Candidate of Engineering Sciences, e-mail: AverinaJM@mail.ru
A. Yu. Kurbatov, Assistant Professor, Department of Innovative Materials and Corrosion Protection, Candidate of Engineering Sciences, e-mail: andreikurbatov@yandex.ru

Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, Moscow, Russia:
P. A. Sakharov, Research Scientist, Laboratory of Oxidation of Organic Substances

At present, one of the most complicated processes is wastewater treatment in the electroplating industry due to a broad range of substances with various properties. Many of them are hazardous toxic substances. Therefore, current treatment processes represent multi-stage process operations. This paper presents an option of treating wastes from the chrome plating area. The authors consider the possibility of using composite coagulants-reducers (CCR) produced by using titanium tetrachloride, a non-standard raw material. Titanium compounds positively influence treatment efficiency, expand an operating range of рН, the settling rate and sludge filtration. At the first stage of studies CCR was produced and tested on a test solution. Residual concentration of chromium (VI) compounds shows the potential for using CCR. During the experiment the authors also studied how impurities of heavy metals and the salt composition of water influenced efficiency of removing chromium (VI) compounds. It was shown that background concentrations of metals and high content of salts had almost no influence on treatment performance, when using titanium (III) chloride and CCR. At the final stage we tested efficiency of actual waste treatment using CCR. The experiment confirmed that titanium compounds added to conventional coagulants significantly increased the settling rate and sludge filtration. This contributes to easier implementation of the process in general.

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