A study of sulfur-rich sludge (71.6% pyrite) dissolution at alkaline conditions (pH ca.9) was investigated using non-stirred and stirred flow-through experiments at room temperature (26 ± 1.2oC) and O2 partial pressure of 0.20 atm. The dissolution rate of pyrite-rich sludge was calculated based on the S release (aqueous SO4) at the steady-state. Results show that: (1) in the nonstirred reactor ...

Indium (In) is commonly hosted in Sn-rich deposits but rarely reported in Sn-poor deposits. However, an In-rich and Sn-poor skarn deposit, the Qibaoshan Cu-Zn-Pb deposit, has been identified in south China. Geochemical analyses were undertaken on 23 samples representing the following mineral assemblages: sphalerite-pyrite, pyrite-chalcopyrite, pyrite-sphalerite-galena-chalcopyrite, pyrite, magn...

a r t i c l e i n f o Keywords: Iron pyrite FeS 2 nanocrystals Thin films Ligand exchange Surface stability Photovoltaic Iron pyrite (FeS 2) is a promising photovoltaic absorber material with a high natural abundance and low cost, but surface defects and low photoresponse inhibit sunlight energy conversion. The surface stability of pyrite FeS 2 nanocrystals synthesized in oleylamine (OLA) with ...

Spontaneous combustion during coal mining operations is a major problem that affects the health and safety of workers causes environmental problems. The phenomenon associated with presence coal, shale, pyrite. In 2020, premature detonation incident occurred at an iron ore mine where waste material contains black carbonaceous shale units known to be spontaneous propensity properties samples shal...

Paracetamol was polymerized in a reaction mixture containing xanthine oxidase, xanthine and paracetamol. This polymerization reaction was not inhibited by allopurinol or KCN, indicating that neither the molybdenum sites nor the iron-sulphur centres of the enzyme were involved in this catalytic activity. Removal of the flavin centres from the enzyme, however, completely abolished paracetamol oxi...

Not much has been written about air cleaning from ozone. The aim of this paper was to demonstrate the possibility of adsorption air cleaning from ozone. The second aim was to investigate the dependence of the efficiency of ozone removal from the air on the height of the adsorber layer and on concentrations of ozone, and to obtain empirical formulas for calculating the efficiency of ozone treatm...

The Eocene Huber Formation, exposed in the CFI Hall mine south of Irwinton, in Wilkinson County, Georgia, displays colored zones that are a consequence of an oxidative weathering front. These zones vary from very light gray (gray) to pinkish white (pink) to very pale yellow (cream) (Munsell N8, 5YR 8/2 and 2.5Y 8/2, respectively) with increasing degree of oxidation. A representative sample from...

Despite the many advantages (e.g., suitable band gap, exceptional optical absorptivity, earth abundance) of pyrite as a photovoltaic material, its low open-circuit voltage (OCV) has remained the biggest challenge preventing its use in practical devices. Two of the most widely accepted reasons for the cause of the low OCV are (i) Fermi level pinning due to intrinsic surface states that appear as...

In a recent paper, Descostes et al. (2004) present data on a series of pyrite oxidation batch experiments conducted near pH 2 and 3 where they demonstrate very well the non-stoichiometric dissolution/oxidation of pyrite in acidic solutions through an extensive laboratory investigation of S/Fe ratios. The authors utilized this data to propose a ‘mechanism’ of pyrite oxidation based on these data...

In this research an interfacial characterization of the pyrite was done. Yet, the biooxidation activity is well explained if the interfacial process is carefully analyzed. Thus, I recommended to request to the authors, to include the ESEM-EDX analysis of the pyrite surface after and before the assays, for each trial, vr. gr. C, T1, T2 and T3, in order to improve the surface characterization and...