original data and description

data tool and discription, especially xps fitting process

Mixed Potential Plays a Key Role in Leaching of Chalcopyrite: Experimental and Theoretical Analysis

The mixed potential plays a key role in leaching of chalcopyrite. Therefore, the impact of Fe²⁺ and Fe³⁺ on chalcopyrite leaching was investigated in this work. Simultaneously, the chalcopyrite passive film was studied by applying cyclic voltammetry (CV), potentiodynamic, potentiostatic, and Tafel polarization. X-ray photoelectron spectroscopy (XPS) was used to analyze the products formed during the electrochemical treatment of chalcopyrite. Furthermore, the band theory was used to analyze the oxidation and reduction of chalcopyrite. High copper extraction percentage was obtained at a low mixed potential or ratio of Fe³⁺/Fe²⁺. The empty states of chalcopyrite overlapped with filled states of Fe²⁺; chalcopyrite captured electrons from Fe²⁺ and was reduced to chalcocite, which was very easily oxidized by Fe³⁺. The Fe dissolves preferentially from the chalcopyrite surface in the potential range from 475 to 700 mV and leave behind a S₂^2– and S_<i>n</i>^2– passive film. The chalcopyrite transpassive dissolution occurs above 700 mV

original data and descriptions from Inhibition mechanism of Ca²⁺, Mg²⁺ and Fe³⁺ in fine cassiterite flotation using octanohydroxamic acid

The existence of metal ions should not be ignored in both hydrometallurgy and flotation. In this study, the effects of Ca²⁺, Mg²⁺ and Fe³⁺ on the flotation performance of cassiterite using octanohydroxamic acid (OHA) as the collector were investigated by micro-flotation tests, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, contact angle, zeta (<i>ζ</i>) potential measurements and atomic force microscopy (AFM) imaging. The results of the flotation and contact angle experiments showed that the addition of Ca²⁺, Mg²⁺ and Fe³⁺ significantly decreased both the recovery and contact angle of cassiterite with pH in the range from 6.0 to 12.0 in the presence of OHA collector. <i>ζ-</i>Potential measurements, solution chemistry analysis and FTIR measurements indicated that the flotation recovery of the cassiterite declined due to the CaOH⁺, MgOH⁺ and Fe(OH)₃ sites on the cassiterite surface. XPS results indicated that the chemisorption of OHA on the cassiterite surface and its adsorption combined with calcium ions’ effects finally changed the chemical properties of the cassiterite surface. The AFM images also revealed that new species Fe(OH)₃ of Fe³⁺ formed and adsorbed on the cassiterite surface at pH 9.0. The adsorption of Fe(OH)₃ reduced the adsorption of OHA on the cassiterite surface, thus the hydrophobicity of cassiterite was deteriorated