Institute of Mining, Far Eastern Branch, Russian Academy of Sciences, Khabarovsk, Russia

K. V. Prokhorov, Leading Researcher, Candidate of Engineering Sciences, kostyan1986_ne@mail.ru

By intensifying the flotation process in modified pulp solutions, an increase in gold and silver by 14.2 % and 10.5 % was obtained, respectively. It is found that after membrane electrolysis, micro and nano bubbles of oxygen and hydrogen can be retained in the anolyte and catholyte, despite the fact that, under normal conditions, oxygen has a high solubility, and hydrogen, on the contrary, has a low solubility in water. With the use of activated solutions, the wetting angle on the treated pyrite surface increases from 53 to 57 degrees. When using a mixture of activated solutions of catholyte and 10 % anolyte, the maximum concentration of dixanthogen is observed on pyrite surface, which speaks about the optimal mechanism of oxidation, affecting xanthate and unaffecting the surface of pyrite. The concentration of desorbed dixanthogen in the studied electrolysis solutions correlates with the results of the wetting angles on the model material, as well as with the results of gold and silver recovery from gold–sulfide–quartz ore in the main experiment. All this confirms the intensifying action of the electrochemical activation of solutions and pulp in the processes of flotation and enrichment of finely dispersed raw materials.
All lab-scale tests were carried out at the Shared-Use Mineral Research Center of the Khabarovsk Federal Research Center, Far Eastern Branch, Russian Academy of Sciences.

The study was supported by Russian Science Foundation grant №24-27-20084, https://rscf.ru/project/24-27-20084/.

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