D. Mendeleev University of Chemical Technology of Russia, Moscow, Russia:

E. N. Kuzin, Associate Professor at the Department of Industrial Ecology, Candidate of Technical Sciences, e-mail: e.n.kuzin@mail.ru
N. E. Kruchinina, Professor, Dean of the Faculty of Biotechnology and Industrial Ecology, Head of the Department of Industrial Ecology, Doctor of Technical Sciences, e-mail: krutch@muctr.ru
T. I. Nosova, Undergraduate Student at the Department of Industrial Ecology, e-mail: nti16041998@gmail.com

This paper considers the applicability of complex titanium coagulants in the treatment of electroplating industry wastewater. Complex titanium coagulants were found to significantly outperform the conventional coagulants containing aluminium or iron compounds in terms of decreasing the concentration of suspended matter (insoluble forms of metals). The average effective dose of complex titanium reagents was 1.5 to 2.0 times lower than that of conventional reagents. Complex titanium reagents proved to be more efficient for removing copper compounds from wastewater after copper plating with complex ammoniumtartrate electrolytes. When compared with aluminium salts, the residual concentration of copper ions and the effective dose of titanium reagents were significantly lower. Due to forming easily soluble complexes with organic ligands and due to hydrolysis inhibition, iron salts did not prove efficient. The authors proved that the use of complex titanium coagulants helps intensify (by more than 20%) sedimentation and filtration of coagulation slurries. This, in turn, will help to significantly raise the efficiency of wastewater treatment facilities and make them more compact. Combined with low consumption of reagents, this can help make wastewater treatment processes a lot more cost-effective. The research data obtained suggest that complex titanium reagents can be efficiently used for treatment of acid-base and copper-bearing wastewater generated by the electroplating industry.

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