Experimental modeling of platinum behavior under hydrothermal conditions (300–500°C and 1 kbar)

X-ray Photoelectron Spectroscopy (XPS) Study of the Products Formed on Sulfide Minerals Upon the Interaction with Aqueous Platinum (IV) Chloride Complexes

“…The increasing industrial demand for PGEs and their limited natural sources require the investigation of the genesis of PGE ores and new approaches to the recovery technologies [4], secondary processes and environmental behavior of engineered PGE species [5,6]. Platinum-group element ores are mainly associated with ultramafic-mafic rocks and, little is known about the interaction of Pt-bearing aqueous solutions with sulfide minerals [7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Platinum-group element deposits of hydrothermal origin exist, and mechanisms of hydrothermal transportation of PGEs [9][10][11][12], including the biological transport and transformation [21][22][23][24] have been studied since the end of the 1980s.…”

“…Platinum usually has low concentrations within base metal sulfides and mainly forms discrete platinum-group minerals (PGMs). Most work has been focused on the experimental study and mathematical modeling of Pt dissolution, and stability of its complex compounds with ligands such as HS − , Cl − , S 2 O 3 2− , OH − , NH 3 [11,12,17,18,22,28,29]. At low temperature conditions, acidic pHs and high redox potential, Pt transport by chloride ions is the most suitable [18,30].…”

Surface-State Assisted Carrier Recombination and Optical Nonlinearities in Bulk to 2D Nonlayered PtS

“…Platinum sulfide (PtS) is the main component of the rare mineral cooperite, which is also the main source of platinum extraction in the mining industry. Over the past 80 years, research on cooperite, or PtS, has mainly focused on structural mechanics, − magnetic susceptibility, high-pressure-induced phase transitions, electronic properties, − synthesis, , and elasticity . However, to date, its optical properties have been little studied, and there are no reports either on its nonlinear optical (NLO) properties or carrier dynamics.…”

“…There are two salient reasons impeding study of the optical properties of PtS. First, the mined cooperite mineral inevitably contains some metal ion impurities such as Pb, Ni, Cu, Fe, , or excess platinum metal which is about 5–7 times larger than the sulfur component in common cooperite. , Second, the materials used in the previously mentioned investigations of the properties of PtS were typically either natural cooperite, with an irregular grain size, , or artificially synthesized PtS in the form of a powder or dispersion. ,, The contamination, irregularities, and small scale, associated with both natural and synthetic PtS, make it difficult to measure its properties without extrinsic effects . As such, inaccuracies and/or misunderstandings may occur if the exact nature of the material studied is not carefully considered, such as the erroneous conclusions on reflection spectra and color values of PtS in earlier studies. , These errors, or gaps in understanding, can be attributed to the poor quality of the synthesized PtS.…”