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

V. A. Brodskiy, Cand. Chem., Senior Researcher, e-mail: vladimir_brodsky@mail.ru
D. Yu. Zhukov, Cand. Eng., Director of Technological Center “Ekokhimproekt”, e-mail: Zhukov.d.i@muctr.ru
Yu. O. Malkova, Leading Engineer, e-mail: jui77_77@mail.ru

The process of electroflotation extraction of dispersed phase of manganese (II-IV) low-soluble compounds from water solutions with different ion composition is examined. The process of forming of dispersed phase in presence of OН^-, CO₃^2-, PO₄^3- ions, as well as flocculants of anion, cation and non-ion types is studied. It was shown that efficiency of electroflotation process depends directly on dispersity and electrokinetic potential of particles, which are determined by acidity and ion composition of the medium. Maximal average hydrodynamic diameter of dispersed phase of low-soluble manganese compounds were observed in the pH area 10-11, what corresponded to minimal solubility of dispersed phase. In this case the process of electroflotation extraction passed with maximal efficiency, extraction degree achieved 96 %. Introduction of cation flocculant in solutions allowed to rise extraction degree up to 98 %. Addition of CO₃^2- and PO₄^3- ions in solutions caused shift of ζ-potential of dispersed phase in the area of negative values (-18 mV and -33 mV respectively), what finalized in complication of forming of flotation complexes “particle - Н₂, О₂ bubbles” and to complication of coagulation processes. Extraction degree did not exceed 10 % in both cases. Addition of cation and non-ion flocculants in the examined solutions allowed to compensate negative charge of dispersed phase, to enlarge this phase and to rise extraction degree of manganese (II) low-soluble compounds to 98 %.

The research was carried out under financial support of Mendeleev University of Chemical Technology of Russia within the framework of VIG-2022-073.
Authors express their gratitude to the D. I. Mendeleev Center for the collective use of scientific equipment for assistance in carrying out the research.

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