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

A. M. Gaydukova, Cand. Eng., Associate Prof., Dept. “Technologies of inorganic substances and electrochemical processes”, e-mail: agaydukova@muctr.ru
V. A. Kolesnikov, Dr. Eng., Prof., Head of Dept. “Technologies of inorganic substances and electrochemical processes”
V. A. Brodskiy, Cand. Chem., Associate Prof., Dept. “Technologies of inorganic substances and electrochemical processes”, e-mail: vladimir_brodsky@mail.ru
A. V. Kolesnikov, Cand. Eng., Associate Prof., Dept. “Innovative materials and corrosion protection”, e-mail: artkoles@list.ru

Investigations of extraction process for carbon materials after sorption purification of aqueous solutions via electroflotation method with removal of ions of heavy and non-ferrous metals are presented in this work. The data on adsorption of some organic compounds on “OU-B” carbon material powders and aluminium hydroxides are observed. The research results of Fe (III) cations (coagulant) influence on extraction efficiency of “OU-A” carbon materials from aqueous solutions are observed. The effect of metal pH and cation nature on surface parameters of carbon material particles, specifically on electrokinetic potential is studied. It is shown that extraction completeness and efficiency depend directly on the value of electrokinetic potential of coal particles; the particles with minimal absolute surface charge value are extracted mostly completely and effectively, if Fe3+ ions are presented in solution. It was determined that size of particles also has the effect on their extraction efficiency. Based on the obtained data of electrokinetic potential of particles, a flocculant was selected; if it is added to the solution, the range of carbon material extracting concentrations expands to 1 g/l. Based on the obtained data on the electrokinetic potential of the particles, a flocculant was selected, which, when adding it to the solution, expands the range of recoverable concentrations of carbon material to 1 g/l. The technological scheme of carbon materials use for purification of waste water using various extraction technologies for dispersed phase is presented.

The research was conducted under financial support of Mendeleev University of Chemical Technology of Russia (project No. З-2020-003).

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