Compounds containing copper are likely candidates to delay iodide migration in environmental media through the formation of sparingly soluble phases. Preliminary experiments showed that iodide was neither sorbed onto chalcopyrite nor by a binary system pyrite/copper(II), although significant amounts of copper were present at the pyrite surface. In the present study, spectroscopic studies (XPS, XANES and EXAFS) were thus performed to determine the nature of sorbed copper species. Although introduced as Cu(II), copper was mainly present at the oxidation state (I) on the pyrite surface suggesting a heterogeneous reduction process. Moreover, copper appeared tetrahedrally coordinated to two sulfur and two oxygen atoms onto the pyrite surface, a chemical environment, which seemingly stabilized the metal and made it unreactive towards iodide.
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http://dx.doi.org/10.1016/j.jcis.2006.07.022 | DOI Listing |
Front Microbiol
January 2025
UPR4301 Centre de Biophysique Moléculaire (CBM), Orléans, France.
We investigated the metabolome of the iron- and sulfur-oxidizing, extremely thermoacidophilic archaeon grown on mineral pyrite (FeS). The extraction of organic materials from these microorganisms is a major challenge because of the tight contact and interaction between cells and mineral materials. Therefore, we applied an improved protocol to break the microbial cells and separate their organic constituents from the mineral surface, to extract lipophilic compounds through liquid-liquid extraction, and performed metabolomics analyses using MALDI-TOF MS and UHPLC-UHR-Q/TOF.
View Article and Find Full Text PDFACS Omega
January 2025
School of Earth Sciences, East China University of Technology, Nanchang, Jiangxi Province 330013, China.
In recent years, the Telaaobao Mineral Area in the Northwestern Ordos Basin has been newly discovered as a uranium mineralization area with its ore-bearing target layer located within the Lower Cretaceous Huanhe Formation, belonging to a new area and a new layer, and has great uranium deposit formation potential. In order to deeply study the issues of the ore-bearing target in this area, such as the petrology, mineralogy, and uranium mineralization of the ore-bearing sandstone, based on the data from field geological investigation and drill core logging, the petrological characteristics of the ore-bearing sandstone of the target layer are preliminarily interpreted using a polarizing microscope and a scanning electron microscope, and the uranium mineral composition, uranium occurrence state, and uranium deposit mineralization are investigated through the electron probe microanalysis technique in this paper. The results show that the target layer sandstone in the study area has the characteristics of proximal deposit and has undergone significant epigenetic alteration and transformation, producing favorable conditions for uranium- and oxygen-containing water transportation and uranium mineralization.
View Article and Find Full Text PDFSci Total Environ
January 2025
School of the Environment, University of Queensland, QLD, Australia.
The transition to net zero emissions requires the capture of carbon dioxide from industrial point sources, and direct air capture (DAC) from the atmosphere for geological storage. Dissolved CO has reactivity to rock core, and while the majority of previous studies have concentrated on reservoir rock or cap-rock reactivity, the underlying seal formation may also react with CO. Drill core from the underlying seal of a target CO storage site was reacted at in situ conditions with pure CO, and compared with an impure CO stream with SO, NO and O that could be expected from hard to abate industries.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
School of Civil Engineering, Southwest Jiaotong University, Chengdu, Sichuan Province 610031, China.
Chemical weathering of lithologies with high geochemical backgrounds such as black shale has been proposed to be a critical source for toxic elements in soil and water systems. However, mechanisms controlling the release, migration and enrichment of toxic elements during black shale weathering are poorly understood. This study utilized a suite of micro analytical techniques such as TESCAN integrated mineral analyzer (TIMA), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), X-ray photoelectron spectroscopy (XPS) and electron micro-probe analysis (EMPA) to elucidate the intimate relationship between mineralogical transformations and elemental behaviors from profile scale to mineral scale.
View Article and Find Full Text PDFSci Rep
December 2024
State Key Testing Laboratory of Vanadium & Titanium, Vanadium and Titanium Resource Comprehensive Utilization Key Laboratory of Sichuan Province, Panzhihua University, Panzhihua, 617000, Sichuan, People's Republic of China.
Pyrite cinder could release more heat to improve he acid decomposition reaction of ilmenite, lower concentrations of sulfuric acid, increase the amount of TiO waste acid reused, reduce titanium gypsum emissions, and promote the green and sustainable development of TiO. Using pyrite cinder as strengthening activator, the continuous acid decomposition conditions for ilmenite were optimized by using response surface methodology based on Box-Behnken design method. The acid decomposition conditions such as acid ilmenite ratio, acid concentration and pyrite cinder dosage mainly affected the reaction temperature, reaction equilibrium, reaction velocity, volatilization degree of water and sulfuric acid, ultimately affecting the solidification degree of the products and reaction yields.
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