Department of the Technology of Inorganic Substances and Electrochemical Processes, D. Mendeleev University of Chemical Technology of Russia, Moscow, Russia:

A. A. Pokhvalitova, Master’s Degree Student, e-mail: pokhvalitova_anastasia@mail.ru
A. M. Gaydukova, Associate Professor, Candidate of Technical Sciences
T. N. Krylova, Postgraduate Student
A. D. Stoyanova, Associate Professor, Candidate of Technical Sciences

This paper describes a series of studies that looked at the extraction of nonferrous metals (such as Cu²⁺, Ni²⁺ and Zn²⁺) from industrial wastewater by electroflotosorption and using powdered carbon sorbents of OU-A and UAF types. Using IR spectroscopy, the authors examined the molecular structure of the considered carbons, as well as the number of acidic and basic functional groups present on their surface. The paper also looks at the effect of various coagulants (AlCl₃, FeCl₃, UltraPAC V-2, TiCl₄) on the removal of the above metals from aqueous systems in neutral and alkaline environments. It was found that the FeCl₃ coagulant helps raise the recovery of Zn²⁺ ions from wastewater when using the UAF sorbent. The recovery of the spent carbon sorbent was 84–94% and that of the FeCl₃ coagulant — 99%. It is proposed to use the UltraPAC V-2 and AlCl₃ coagulants to increase the recovery of Cu²⁺ and Ni²⁺ ions from wastewater. It was established that a 98–99% coagulant recovery can be reached when using the OU-A carbon. At the same time, more than 90% of the spent sorbent can be recovered. The paper considers a multicomponent system containing copper, zinc and nickel ions. It was established that the method of electroflotosorption and the use of the UAF carbon sorbent help remove all of the copper (II) ions from the aqueous system in view. The paper contains a process diagram for wastewater treatment that describes a combination technique for removing non-ferrous metal ions. For post-treatment, it is proposed to use sorption columns following the electroflotosorption stage. Sorption columns help bring the concentrations of metal ions to MPC levels.
This research was funded by D.Mendeleev University of Chemical Technology of Russia under the strategic academic leadership programme Prioritet-2030 No. ВИГ_2022_002.

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