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

A. V. Kolesnikov, Cand. Eng., Associate Prof., Dept. of Innovation Materials and Corrosion Protection, e-mail: artkoles@list.ru
D. Yu. Zhukov, Cand. Eng., Associate Professor, Advisor to the Rector
V. A. Kolesnikov, Dr. Eng., Prof., Head of Dept. “Technologies of inorganic substances and electrochemical processes”

Experimental data on the electroflotation extraction of iron (III) hydroxide from aqueous solutions of various compositions in the presence of surfactants and organic compositions are presented. The high efficiency of the electroflotation process for the extraction of powdered materials – OU-B, TiO₂, SiC coals in the presence of the FeCl₃ coagulant and the FeCl₃ - surfactant composition was shown to be high. The degree of extraction reaches 90 – 98 %. A high degree of extraction in the presence of Fe (III) is associated with an increase in the size of the dispersed phase of Fe(OH)₃ – OA to 50–60 μm and a decrease in the negative electrokinetic potential. The influence of flocculants and surfactants of various nature is not large, the degree of extraction of OU-B does not exceed 40 – 50 %. It has been shown that surfactants of various nature are subjected to sorption on freshly formed iron (III) hydroxide deposits. The highest sorption value is observed for cationic surfactants at their high concentration in solution (500 - 750 mg/l).
The work was carried out with the financial support of the D. I. Mendeleev UCTR (project No. З-2020-004).

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