Effect of Cu2+ activation on interfacial water structure at the sphalerite surface as studied by molecular dynamics simulation

Abstract

Keywords:MDS DFT Contact angle Interfacial water structure In the first part of this paper, an experimental contact angle study of fresh and Cu 2+ activated sphalerite-ZnS surfaces as well as the covellite-CuS (001) surface is reported describing the increased hydrophobic character of the surface during Cu 2+ activation. In addition to these experimental results, fresh sphalerite-ZnS (110), copper-zinc sulfide-CuZnS 2 (110), villamaninite-CuS 2 (100), and covellite-CuS (001) surfaces were examined using Molecular Dynamics Simulation (MDS). Our MDS results on the behavior of interfacial water at the fresh sphalerite-ZnS (110), copper-zinc sulfide-CuZnS 2 (110), villamaninite-CuS 2 (100), and covellite-CuS (001) surfaces include simulated contact angles, water number density distribution, water dipole orientation, water residence time, and hydrogen-bonding considerations. The copper content at the Cu 2+ activated sphalerite surface seems to account for the increased hydrophobicity as revealed by both experimental and MD simulated contact angle measurements. The relatively greater hydrophobic character developed at the Cu 2+ activated sphalerite surface and at the copper sulfide surfaces has been described by MDS, based on the structure of interfacial water and its dynamic properties.

Emerging Trends of Computational Chemistry and Molecular Modeling in Froth Flotation: A Review

“…MD simulations based on the Universal force field parameters and Mulliken partial charges were conducted to assess the hydrophilicity of Cu 2+ activated sphalerite surface . The wettability of the pristine and the Cu 2+ -activated sphalerite was compared by calculating the contact angle, water number density distribution, water dipole orientation, and water residence time, among other things.…”

“…351 MD simulations based on the Universal force field parameters and Mulliken partial charges were conducted to assess the hydrophilicity of Cu 2+ activated sphalerite surface. 352 The wettability of the pristine and the Cu 2+ -activated sphalerite was compared by calculating the contact angle, water number density distribution, water dipole orientation, and water residence time, among other things. Although using a generic force field combined with Mulliken partial charges should be treated cautiously, the MD results confirmed that activating the sphalerite surface with Cu 2+ increases the mineral hydrophobicity due to decreased surface polarity.…”

Transparent, Conducting Self‐Assembled CuS Nanostructures at and beyond Liquid‐Liquid Interface and their Electrocatalytic Properties

“…At higher concentration of copper precursor, the formation of protruding nanosheets of CuS in the aqueous phase and self-assembled spheres in the organic phase could be due to the partial wettability of CuS with water (contact angle of water with (001) plane of covellite CuS is 65°) and adsorption of electrolyte (Na 2 S). [39] CuS crystal structure is polar in the c-direction. During the initial stage of vertically growing CuS nanosheets, CuS clusters initially form, which can be wetted by water and adsorption of electrolyte.…”

Study of process water effect on the activation of sphalerite during differential flotation of Pb-Cu-Zn

“…Given the above, the presence of the Cu 2+ and Pb 2+ ions in process water within the differential flotation of Cu-Pb-Zn becomes relevant, and the fact of monitoring its variation to avoid inadvertently activating the Sphalerite is of utmost importance. The activation of Sphalerite by Cu 2+ ions has been previously studied (Gerson et al, 1999;Rao et al, 2011;Jin et al, 2015;Chen and Yoon, 2000) and it has been shown that Cu 2+ ions activate Sphalerite according to the following mechanism:…”

“…During the flotation of Pb-Cu-Zn sulfides ores, there are Cu 2+ , Pb 2+ , and Zn 2+ ions present. The Cu 2+ and Pb 2+ ions frequently cause inadvertent Sphalerite activation, promoting a reduction in the Cu concentrate grade (Rashchi et al, 2002;Jin et al, 2015;Aikawa et al, 2020). For example, this phenomenon occurs at Cozamin mine, located in Zacatecas, México, where after the grinding process, the pulp is fed into the flotation process: It begins with bulk copper-lead concentrate flotation with depressed zinc, and continues with the copper-lead separation and later with a subsequent flotation in a zinc circuit.…”