The influence of silver ion on the electrochemical response of chalcopyrite and other mineral sulfide electrodes in sulfuric acid

Gold deposition on pyrite and the common sulfide minerals: An STM/STS and SR-XPS study of surface reactions and Au nanoparticles

“…Silver has been reported to form mainly silver sulfide Ag 2 S (Price and Warren, 1986;Buckley et al, 1989;Scaini et al, 1997;Barzyk et al, 2002), although photoelectron Ag 5d spectra with Ag 5d 5/2 peak at about 368.2 eV and Ag M 4 N 45 N 45 Auger spectra (not shown in Figures) do not allow differentiating between metallic silver, Ag 2 S and adsorbed silver species reliably. The S 2p spectra of reacted minerals show minimal contributions from polysulfide and substantially increased signals from monosulfide at about 161.4 eV.…”

Electrochemical characterization of chemical species formed during the electrochemical treatment of chalcopyrite in sulfuric acid

“…It is worth noting that in the literature there are only a few studies on chalcopyrite dissolution in the extreme regions (either low or high) regions of the potential, and these do not consider that at each value of the potential, different oxidation processes take place. For example, Price and Warren [7] and Arce and González [14] explored the low potential regions (−0.185 V ≤ E ≤ 1.015 V versus SHE) and observed the formation of a voltammetric peak at E ∼ = 0.565 V versus SHE, attributed to the passivation phenomenon in which a non-stoichiometric polysulfide (deficient in copper and iron) is formed. On the other hand, Elsherief studied more anodic regions of the potential (−0.585 V ≤ E ≤ 1.615 V versus SHE) The voltammogram was traced starting from the OCP at 0.100 V/s.…”

“…The most explored region has been that of −0.185 V ≤ E ≤ 1.015 V versus SHE [6,7,11,13], perhaps due to the fact that the chalcopyrite oxidation and reduction processes, associated with copper sulfides (CuS, Cu 5 FeS 4 and Cu 2 S), can only be formed in this potential interval. However, the window of −0.585 V ≤ E ≤ 1.615 V versus SHE has been relatively neglected [15,16].…”

Probing the effect of aqueous impurities on the leaching of chalcopyrite under controlled conditions

“…Previous studies have reported that the chalcopyrite leach rate increases in the presence of Cl − (Lu et al, 2000), Ag + (Miller et al, 1981;Price and Warren, 1986) or carbon particulate aggregates (Wan et al, 1984). All these studies, except the study by Price and Warren (1986), found, through SEM studies, that the product sulfur becomes more porous in the presence of the catalysts (i.e.…”