Effect of high-power electromagnetic pulses and dielectric barrier discharges on physicochemical and flotation properties of perovskite

Abstract

The methods of FTIR, SEM–EDX, microhardness test, electrokinetic potential and contact angle measurements, as well as the sorption and flotation experiments are used to study the influence of high-power electromagnetic pulses (HPEMP) and dielectric barrier discharge (DBD) on the structural, physicochemical and flotation properties of perovskite (Afrikanda deposit). The analysis of FTIR data shows that short treatment times (t treat = 10 t 0÷30 s) lead to opposite changes in the surface condition of perovskite: oxidation (hydration) of the surface in case of HPEMP and deoxidizing (dehydration) under DBD. According to SEM results, the surface of perovskite undergoes destruction as a result of HPEMP and DBD treatment. The surface of some areas of the samples is modified with the formation and opening of deep parallel cracks, most likely due to the polysynthetic twinning typical of perovskite crystals; the subparallel pyramidal protrusions are also observed in some surface areas. The determined morphological changes cause softening and a monotonic decrease in the microhardness of the mineral surface with an increase of the HPEMP and DBD (plasma) treatment times (ttreat = 0 t 0÷150 s) by ΔHVmax V = 27 x 7÷33%. The effect of HPEMP and DBD on the physicochemical properties of the mineral surface represents a shift in the electrokinetic potential towards positive values, an increase in the contact angle (t treat = 10 t 0÷30 s), as well as the improved adsorption of the collector and the higher flotation activity of perovskite by ~ 10–15%. The authors express their gratitude to Candidate of Geological and Mineralogical Sciences E.V. Koporulina and to Candidate of Engineering Sciences N.E. Anashkina for their help in the experimentation.The study was supported by the Ministry of Science and Higher Education of the Russian Federation, Project No. 13.1902.21.0018, Agreement No. 075-15-2020-802.