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Stretchable conductors based on nanopercolation networks have garnered great attention for versatile applications. Carbon nanotubes (CNTs) are well‐suited for creating high‐efficiency nanopercolation networks. However, the weak interfacial shear strength (IFSS) between CNTs and elastomer hardly dissipates the deformation energy and thus deteriorates the conductive network. Herein, a novel sulfur‐containing CNTs attached with abundant graphene nanoflaps using a two‐step sulfidation strategy are developed. The sulfur functionality creates a strong interfacial interaction with the elastomer polymer, while the graphene nanoflaps provide an enhanced, intertwined shear interface with elastomer that is capable of efficiently dissipating the deformation energy. As a result, the optimized nanocomposite significantly improves the IFSS between nanofiller and elastomer, displaying remarkable conductive robustness (ΔR/R0≈1.8 under 200%), superior stretchability (> 450%), and excellent mechanical durability (≈30 000 cycles). Moreover, the nanocomposite demonstrates excellent Joule heating efficiency (≈150 °C in 12 V), stretchable heating conversion (≈200%), and long‐term stability (> 24 h). To illustrate its capabilities, the nanocomposite is used to track human physiological signals and perform electric‐thermal actuating as a set of soft tongs. It is believed that this innovative approach will provide value for the development of wearable/stretchable devices, as well as human‐machine interaction, and bio‐robotics in the future. [ABSTRACT FROM AUTHOR]

The quantum dot FeS 2 materials coupled with reduced graphene oxide have been fabricated by the sulfidation of Fe-MOF precursors. The constructed materials possess numerous rapid ion channel and abundant active area derived from the quantum dot structure, delivering the high-active catalysis ability caused by the formed Fe nanoclusters during potassiation/depotassiation process. This strategy can synchronously guarantee rapid ion transmission, reaction reversibility and structure tolerance of FeS 2 materials, then expressing a strengthening capability for accommodating K+-ions. [Display omitted] • The quantum dot FeS 2 has been fabricated by the sulfidation of Fe-MOF. • Its shortened ion channel enhances the reaction kinetics. • Its absorption and catalysis actions suppress the polysulfide shuttle effect. Though numerous framework structures have been constructed to strengthen the reaction kinetics and durability, the inevitable generation of polysulfide dissolution during conversion-process can cause irreparable destruction to ion-channel and crystal structure integrality, which has become a huge obstacle to the application of metal-sulfide in potassium-ion batteries. Herein, the quantum dot structure with catalytic conversion capability is synchronously introduced into the design of FeS 2 anode materials to heighten its K+-storage performance. The constructed quantum dot structure anchored by the graphene with space-confinement effect can shorten the ion diffusion path and enlarge the active area, thus accelerating the K+-ions transmission kinetics and absorption action, respectively. The intermediate phase of formed Fe-nanoclusters possesses high-active catalysis ability, which can effectively suppress the polysulfide shuttle combined with the enhanced absorption effect, fully guaranteeing the structure stability and cycling reversibility. Predictably, the fabricated quantum dot FeS 2 can express a prominent advantage in rapid potassiation/depotassiation processes (518.1 mAh g−1, 10 A g−1) and a superior cycling lifespan with gratifying reversible capacity at superhigh rate (177.7 mAh g−1, 9000 cycles, 5 A g−1). Therefore, engineering quantum dot structure with self-induced catalysis action for detrimental polysulfide is an achievable strategy to implement high-performance sulfide anode materials for K-ions accommodation. [ABSTRACT FROM AUTHOR]

In this study, flotation experiments, zeta potential, XPS, AFM, SEM-EDS, and contact angle measurements were performed to study the influence of ammonium carbamate (CH6N2O2) on the sulfidation flotation of chrysocolla. The results of the sulfidation flotation experiments showed that the recovery of chrysocolla increased more than 40% on the optimal condition after adding ammonium carbamate. In addition, the zeta potential of samples with ammonium carbamate was clearly higher than ores for pH > 6, which was due to the complexation reaction between ammonium carbamate and copper ion on the surface of chrysocolla samples. The activity of copper adsorption has also been improved. Furthermore, the XPS data indicated that the content of Cu-S compounds on the mineral surface has been significantly enhanced after ammonium carbamate complex sulfidation. The chemical analysis of the solution led to the same conclusion. The AFM results showed that ammonium carbamate had a positive impact on the adsorption of minerals surface, and increased the flotation recovery. It can be deduced from the SEM-EDS analysis that the surface of chrysocolla better combined with S-, and more Cu-S components were generated on the surface, which led to 1.04% increase of S atomic concentration. Finally, the contact angle measurements showed that the water contact angle of chrysocolla after adding ammonium carbamate could reach 90.4°, which proved that the sulfidation improved the floatability of the chrysocolla sample. [ABSTRACT FROM AUTHOR]

Developing noble-metal-free bifunctional electrocatalysts at an effective cost and with a high catalytic ability for hydrogen production via water-splitting is imperative, although a great bottleneck remains. Herein, we present a plasma engraving strategy to synthesize N-doped CoFeS on cobalt foam with a multi-interface and defect hierarchical structure. The N-doped CoFeS was synthesized using an ion exchange method to prepare the CoFe LDH precursor, followed by sulphidation and plasma-assisted engraving in nitrogen gas. The N-doped CoFeS requires an overpotential of 230 mV for the OER and 26 mV for the HER to reach a current density of 10 mA cm−2. It also shows an excellent catalytic activity towards overall water splitting, which requires a low voltage of 1.61 and 1.80 V to achieve a current density of 10 and 50 mA cm−2, respectively, in 1 M KOH. The super-catalytic properties can be attributed to the interface and defect structure, which induces a high intrinsic activity, a superior transfer coefficient, and abundant active sites. This work presents a novel approach to prepare noble-metal-free electrocatalyst with plenty of interface and defect sites for overall water splitting. [ABSTRACT FROM AUTHOR]

Experimental studies aimed at the modeling of interaction processes of sulfur-bearing metasomatic agents with mantle silicates and assessing the effect of sulfur concentration on olivine sulfidation were carried out in the Fe,Ni-olivine—sulfur system using the high-pressure multi-anvil apparatus BARS (1050 and 1450°C, 6.3 GPa, 40–60 h, sulfur concentrations (Xs) 0.1, 2, and 6 mol %). It has been established that as a result of the recrystallization of Fe,Ni-olivine in a sulfur melt, Fe and Ni are extracted from olivine into this melt, and formation of Fe,Ni-sulfides (or sulfide melts) and low-iron, low-nickel silicates takes place. The key indicator characteristics of the olivine sulfidation process are determined depending on the temperature and sulfur concentration, including characteristic phase assemblages, regularities in the evolution of the chemical compositions of mineral and melt phases, and structural features of olivine crystals. It has been experimentally established that reducing sulfur-bearing metasomatic agents, even in minimal concentrations and at relatively low temperatures, are capable of dissolving and transporting mantle silicates and sulfides, and can play an important role in sulfide ore formation in the mantle. [ABSTRACT FROM AUTHOR]

Copper smelting slag is the largest solid waste produced in copper-making process, and slow cooling beneficiation technology is the most widely used method in recovering remaining treasures from the slag. The phase transition law and element distribution behaviors of the copper smelting slag in the cooling process have significant importance, and they have been experimentally investigated in the present study. CaS, which was produced from the reductive decomposition of gypsum residue, has been added for sulfidation purposes to improve the recovery. Fayalite, glassy slag, hercynite, magnetite, and matte were major phases in the final slag, and the adding amount of CaS had a small effect on the phase transition process. However, the cooling rate had a large effect on the slag phase composition. When decreasing the cooling rate, the mass fraction of glassy slag decreased dramatically. The distribution behavior of Fe, Cu, Zn, Pb, Se, Te, and Ag changed when increasing the CaS adding dosage, and that of Si, Ca, Al, and Mg changed slightly. The initial slag composition also influenced the element distribution behavior. When changing the CaS excess coefficient, the distribution behavior of As and Bi changed slightly in the slag with the initial Fe/SiO2 mass ratio of 1.8. But when the smelting slag had the Fe/SiO2 mass ratio of 1.0 and 1.3, more As entered the glassy slag when increasing the CaS adding dosage. Less Ca reported to the glassy slag when decreasing the cooling rate, and more Cu, Pb, Zn, Se, Te, and Ag entered the matte phase, but part of them were lost in the cooling process. [ABSTRACT FROM AUTHOR]

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This paper aims to characterize and test the stability of sulfuric natural water (SNW) from Sebau East Lombok as a sulfidation agent for several dissolved metals (Mn, Cu, Pb and Fe). The parameters used for SNW characterization are temperature, pH, DO, BOD, COD, TSS, and TDS. The sample was divided into two categories, namely the sample with preservation treatment and the sample without preservation, to study the stability of SNW. The SNW stability was determined by observing the SNW parameters in both samples at a storage time of 5, 10, 15 and 20 days and reacting them with dissolved metals. The SNW with preservation had reduced sulphide levels from day 1 to day 20, ranging from 59.24 mg/L to 17.70 mg/L, whereas the sample without preservation had decreased sulphide concentration from 52.46 mg/L to 9.56 mg/L. Furthermore, the SNW with preservation has a relatively superior metal reduction ratio than the sample without preservation. The maximum value of the deposition ratio for Mn metal was obtained on the fifth day with 57.60%, 83.45% for Cu, and 91.87% for Pb. This trend is not applicable for Fe, whereas the highest reduction (87.23%) was obtained on the the15th day's storage. [ABSTRACT FROM AUTHOR]

In this study, the biochar (BC) produced from sawdust, sludge, reed and walnut were used to support sulfidation of nano-zero-valent-iron (S-nZVI) to enhance nitrate (NO 3 − -N) removal and investigate the impact on greenhouse gas emissions. Batch experiment results showed the S-nZVI/BC sawdust (2:1, 500) , S-nZVI/BC sludge (2:1, 900) , S-nZVI/BC reed (2:1, 700) , and S-nZVI/BC walnut (2:1, 700) respectively improved NO 3 − -N removal efficiencies by 22%, 20%, 3% and 0.1%, and the selectivity toward N 2 by 22%, 25%, 22% and 18%. S-nZVI uniformly loaded on BC provided electrons for the conversion of NO 3 − -N to N 2 through Fe0. At the same time, FeS x layer was formed on the outer layer of ZVI in the sulfidation process to prevent iron oxidation, so as to improve the electrons utilization efficiency After adding four kinds of S-nZVI/BC into constructed wetlands (CWs), the NO 3 − -N removal efficiencies could reach 100% and the N 2 O emission fluxes were reduced by 24.17%-36.63%. And the average removal efficiencies of TN, COD, TP were increased by 21.9%, -16.5%, 44.3%, repectively. The increasing relative abundances of denitrifying bacteria, such as Comamonas and Simplicispira , suggested that S-nZVI/BC could also improve the process of microbial denitrification. In addition, different S-nZVI/BC had different effects on denitrification functional genes (narG, nirk, nirS and nosZ genes), methanotrophs (pmoA) and methanogenesis (mcrA). This research provided an effective method to improve NO 3 − -N removal and reduce N 2 O emission in CWs. Graphical Abstract [Display omitted]. [ABSTRACT FROM AUTHOR]

The emerging energy and environmental concerns nowadays are highlighting the need to turn to clean fuels, such as hydrogen. In this regard, hydrogen sulfide (H2S), an abundant chemical compound found in several natural sources and industrial streams, can be considered a potential carbon-free H2 source through its decomposition. In the present work, the H2S decomposition performance of Co3O4/CeO2 mixed oxide catalysts toward hydrogen production is investigated under excess H2O conditions (1 v/v% H2S, 90 v/v% H2O, Ar as diluent), simulating the concentrated H2S-H2O inflow by the Black Sea deep waters. The effect of key operational parameters such as feed composition, temperature (550–850 °C), and cobalt loading (0–100 wt.%) on the catalytic performance of Co3O4/CeO2 catalysts was systematically explored. In order to gain insight into potential structure-performance relationships, various characterization studies involving BET, XRD, SEM/EDX, and sulfur elemental analysis were performed over the fresh and spent samples. The experimental results showed that the 30 wt.% Co/CeO2 catalyst demonstrated the optimum catalytic performance over the entire temperature range with a H2 production rate of ca. 2.1 μmol H2∙g−1·s−1 at 850 °C and a stable behavior after 10 h on stream, ascribed mainly to the in-situ formation of highly active and stable cobalt sulfided phases. [ABSTRACT FROM AUTHOR]

[Display omitted] Design hybrid metal sulfides-based anode materials is one of the most effective approaches to improve the performance of sodium-ion batteries (SIBs). However, owing to the huge volume expansion, the capacity of sulfide-based anode will decay significantly after repeated charge/discharge processes. Herein, we reported the successful demonstration of anode material based on concaved NiS 2 @CoS 2 nanocube (NCSC) via a chemical etching strategy, which was derived from etching and sulfidation of Ni-Co coordination polymers (NiCoCP) precursor. The obtained NCSC anode materials deliver a high specific sodium storage capacity of 848 mAh g−1 at 0.1 A g−1 and a stable cyclability of 572 mAh g−1 at 5 A g−1 after 830 cycles. This special etching strategy exploit a novel way for the design and preparation of high-performance anode materials for SIBs. [ABSTRACT FROM AUTHOR]

Copyright of Nonferrous Metals (Mineral Processing Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It is of great scientific and practical importance to explore the mechanisms of accelerated degradation of Hexachlorobenzene (HCB) in soil. Both iron oxide and dithionite may promote the reductive dechlorination of HCB, but their effects on the microbial community and the biotic and abiotic mechanisms behind it remain unclear. This study investigated the effects of goethite, dithionite, and their interaction on microbial community composition and structure, and their potential contribution to HCB dechlorination in a paddy soil to reveal the underlying mechanism. The results showed that goethite addition alone did not significantly affect HCB dechlorination because the studied soil lacked iron-reducing bacteria. In contrast, dithionite addition significantly decreased the HCB contents by 44.0–54.9%, while the coexistence of dithionite and goethite further decreased the HCB content by 57.9–69.3%. Random Forest analysis suggested that indicator taxa (Paenibacillus, Acidothermus, Haliagium, G12-WMSP1, and Frankia), Pseudomonas, richness and Shannon’s index of microbial community, and immobilized Fe content were dominant driving factors for HCB dechlorination. The dithionite addition, either with or without goethite, accelerated HCB anaerobic dechlorination by increasing microbial diversity and richness as well as the relative abundance of the above specific bacterial genera. When goethite and dithionite coexist, sulfidation of goethite with dithionite could remarkably increase FeS formation and then further promote HCB dechlorination rates. Overall, our results suggested that the combined application of goethite and dithionite could be a practicable strategy for the remediation of HCB contaminated soil.

Ultralong nanowires with ultrahigh aspect ratios exhibit high flexibility, and they are promising for applications in various fields. Herein, a cadmium oleate precursor hydrothermal method is developed for the synthesis of ultralong nanowires of cadmium phosphate hydroxide. In this method, water-soluble cadmium salt is used as the cadmium source, water-soluble phosphate is used as the phosphorus source, and sodium oleate is adopted as a reactant to form cadmium oleate precursor and as a structure-directing agent. By using this method, ultralong nanowires of cadmium phosphate hydroxide are successfully synthesized using CdCl2, sodium oleate, and NaH2PO4 as reactants in an aqueous solution by hydrothermal treatment at 180 °C for 24 h. In addition, a new type of flexible fire-resistant inorganic paper with good electrical insulation performance is fabricated using ultralong nanowires of cadmium phosphate hydroxide. As an example of the extended application of this synthetic method, ultralong nanowires of cadmium phosphate hydroxide can be converted to ultralong CdS nanowires through a convenient sulfidation reaction. In this way, ultralong CdS nanowires are successfully synthesized by simple sulfidation of ultralong nanowires of cadmium phosphate hydroxide under mild conditions. The as-prepared ultralong nanowires of cadmium phosphate hydroxide are promising for applications as the precursors and templates for synthesizing other inorganic ultralong nanowires and have wide applications in various fields.

This study conducts low-vacuum sulfidation to form a sulfidation layer on the serpentinite-derived magnesium iron silicate, thereby enhancing its electrochemical properties. Results show (Mg,Fe)2SiO4 calcined at 900 °C has the best crystallinity, and the cubic FeS2 is synthesized on the surface of the orthorhombic magnesium iron silicate (MFS). Two distinct charge plateaus can be distinguished during the first charge process, and the discharge capacities increased significantly. This study confirms that the surface FeS2 layer provides extra ion pathways, allowing more lithium/magnesium ions to be extracted and inserted in the serpentinite-derived magnesium iron silicate. Accordingly, the serpentinite electrode boasts straightforward exploitation with low-cost advantages and potential.

The B prospect is located at the southeast of the Chatree gold-silver deposit. The mineralization is hosted in the Late Permian-Early Triassic Chatree volcanic sequence consisting of volcaniclastic and volcanogenic-sedimentary rocks ranging in composition from basaltic andesite to rhyolite. At the study area, the total thickness of volcanic succession is about 300 meters, and the succession can be divided into 3 main stratigraphic units from bottom to top, namely 1) porphyritic andesite unit (Unit 3), 2) polymictic intermediate breccia unit (Unit 2), and 3) volcanogenic sedimentary unit (Unit 1). The ore zones are mainly confined to polymictic intermediate breccia and volcanogenic sedimentary units (Unit 1 and 2). At least 3 stages of mineralization have been identified, namely 1) quartz-pyrite (Stage 1), 2) quartz-chlorite-calcite-sulfide-electrum (Stage 2), and 3) quartz-calcite (Stage 3) veins/veinlets. Gold occurs chiefly in Stage 2 mineralization which is characterized by typical vein textures of low sulfidation epithermal deposit (e.g., crustiform, colloform banding, and comb textures). Pyrite is the primary sulfide mineral with minor sphalerite, chalcopyrite, and galena. Gold occurs as electrum with fineness ranging from 506 to 632. The hydrothermal alteration at B prospect is composed of 2 main types: (1) quartz-adularia (silicic alteration) assemblage close to ore zone and (2) adularia-quartz-illite-calcite-chlorite (phyllic alteration) assemblage distal to ore zone. Based on characteristics of mineral assemblages, textures, and alterations, the mineralization at B prospect can be classified as a low sulfidation epithermal gold-silver style deposit. [ABSTRACT FROM AUTHOR]

The electron-rich Fe-based bulk catalysts are developed to promote the hydrodesulfurization (HDS) performance of dibenzothiophene (DBT). In this study, the Fe-Ti bulk catalyst was modified by the SO 4 2- species to investigate the dispersibility, acidity, electron effect, and isolation effect impacting on HDS performance for DBT. Besides, as sulfidation degree (SD) improves, more the coordinately unsaturated sites (CUSs) will be available for the DBT molecules to be adsorbed and desulfurized that is conducive to the improvement of HDS performance for DBT over Fe-based bulk catalysts. Eventually, compared with Fe-Ti bulk catalyst, the HDS rate of DBT has a remarkable increase from 7.8% to 29.9%, 41.5% to 65.0%, and 70.2% to 90.5% under the reaction temperature with 300, 320, and 340 °C upon the introduction of the SO 4 2- species for 0.3-SO 4 2-/Fe-Ti catalyst, respectively. On the one hand, the Ti species can improve the conversion of electrons to Fe species that form electron-rich Fe-based catalysts, resulting in the improvement of the Fe-based bulk catalysts activity. On the other hand, the addition of SO 4 2- species not only promote the SD by forming the Fe(III)-S and Fe1‐xS species but also strengthen the electron effect between Ti and Fe species, which is conducive to the improvement of HDS performance for DBT. In addition, the SO 4 2- species also worked as an "isolate agent", and can promote increasing the SD for this series of Fe-based bulk catalysts to improve the HDS rate of DBT. Thus, exploring the impact of SO 4 2- species on the HDS performance of Fe-based catalysts is a promising direction for the design and development of environmentally friendly and economical low-cost HDS catalysts in the field of fossil fuel processing. [Display omitted] • The impact of SO 4 2- on the HDS performance of dibenzothiophene were studied. • The electron-rich Fe-based bulk catalyst result in the improvement of HDS performance. • The SO 4 2- species worked as an "isolate agent" can increase the SD in Fe-based bulk catalysts. • The impact of reducibility and acidity on HDS in Fe-based bulk catalysts were studied. [ABSTRACT FROM AUTHOR]

Herein, a series of mesoporous NiMo/LaAlOx with various La contents were constructed through a solvent evaporation‐induced self‐assembly protocol, and their catalytic activities were investigated for hydrodesulfurization (HDS) of 4,6‐DMDBT. It has been confirmed that the incorporation of La influences the electronic structure and morphology of NiMoS active phase. The lower amount of La (x ≤ 1.0 wt.%) could facilitate the formation of "Type II" NiMoS phase by weakening the interaction of Mo‐O‐Al leakage and promoting the sulfidation of both Mo and Ni species as well as increasing the ratio of "Type II" NiMoS phase, thereafter boosting the HDS performances. Further increasing La incorporation, however, leads to the generation of inactive NiSx phase and decrease of NiMoS active phase proportion, the HDS activities of corresponding catalysts were suppressed. NiMo/LaAlOx‐1.0 exhibits the highest activity for 4,6‐DMDBT HDS because of its moderate metal‐support interaction, optimal morphology and the largest proportion of "Type II" NiMoS active phase. [ABSTRACT FROM AUTHOR]

Unraveling atomic‐level active sites of layered photocatalyst towards low‐concentration CO2 conversion is still challenging. Herein, the yield and selectivity of photocatalytic CO2 reduction of the Aurivillius‐related oxide semiconductor Bi2O2SiO3 nanosheet (BOSO) were largely improved using a surface sulfidation strategy. The experiment and theoretical calculation confirmed that surface sulfidation of the Bi2O2SiO3 nanosheet (S‐BOSO, 6.28 nm) redistributed the charge‐enriched Bi sites, extended the solar spectrum absorption to the whole visible range, and considerably enhanced the charge separation, in addition to creating new reaction active sites, as compared to pristine BOSO. Subsequently, surface sulfidation played a switchable role, wherein S‐BOSO showed a very high CH3OH generation rate (12.78 µmol g−1 for 4 h, 78.6% selectivity) from low‐concentration CO2 (1000 ppm) under visible light irradiation, which outperforms most of the state‐of‐the‐art photocatalysts under similar conditions. This study presents an atomic‐level modification protocol for engineering reactive sites and charge behaviors to promote solar‐to‐energy conversion. [ABSTRACT FROM AUTHOR]

Sulfidated nanoscale zerovalent iron (S-nZVI) supported on a flower spherical Mg(OH)2 with different Mg/Fe ration were successfully synthesized. The synthesized materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET), and X-ray photoelectron spectroscopy (XPS). The results showed that S-nZVI particles were well dispersed on the petals of the flower spherical Mg(OH)2. The influence of factors, including the initial solution pH, Mg/Fe, S/Fe were studied. The trichloroethylene (TCE) adsorption data on Mg(OH)2 and S-nZVI @Mg(OH)2 fit well to a Langmuir isotherm model, and the maximum adsorption of S-nZVI @Mg(OH)2 was 253.55 mg/g, which was 2.6-fold of S-nZVI. Meanwhile, the S-nZVI @Mg(OH)2 composite expanded the pH selection range of S-nZVI from 2 to 11. Cycling experiments showed that removal rate was 58.3% for the 5th cycle. TCE removal was due to synergistic action of reduction coupled with adsorption. During this process, 65.43% of total remove TCE from ion chromatography data was reduced and 34.57% of total remove TCE was adsorbed finally. At the same time, adsorption favors reduction. These observations indicated that the S-nZVI @Mg(OH)2 can be considered as potential adsorbents to remove TCE for environment remediation. [ABSTRACT FROM AUTHOR]

Exploring low-cost and high-efficiency OER catalysts is still a challenge. In this paper, self-supporting catalyst-Ni 3 S 2 @FeCrMoS x /NF was prepared using metal organic frameworks as templates. The morphology of the pre-catalyst has been deeply restructured after the sulfidation reaction, which significantly changes the composition and catalytic performance of the catalyst. The overpotential of Ni 3 S 2 @FeCrMoS x /NF is only 144 mV and 241 mV at a current density of 10 and 50 mA cm−2 respectively, the Tafel slope is as low as 45 mV dec−1. And it can maintain good electrochemical stability at a high current density of 100 mA cm−2. The outstanding OER performance of Ni 3 S 2 @FeCrMoS x /NF can be attributed to the increase of electrochemical surface area after sulfidation, the synergistic effect among multi-metals and the synergistic effect of polymetallic sulfides generated by sulfidation. [Display omitted] • The morphology of FeCrMo-MOF has been deeply restructured after the sulfidation. • The Mo–S bond is helpful for the improvement of the OER performance of the catalyst. • The synergistic effect among metal sulfides promotes the OER performance of the catalysts. • Ni 3 S 2 @FeCrMoS x /NF showed excellent OER and HER performance and good stability. [ABSTRACT FROM AUTHOR]

Cobalt molybdenum carbide supported on activated carbon was synthesized and the effect of sulfiding in catalytic activity of the glycerol trioleate deoxygenation process (DOX) was evaluated. Prior to glyceryl trioleate deoxygenation reactions, the catalyst was reduced and sulfided with CS2/H2. CoMo/CA carbide was characterized by specific area (B.E.T), X-ray diffraction (DRX), elemental analysis (CHON-S), potentiometric titration with butylamine and X-ray photoelectron spectroscopy (XPS). The surface area of the CoMo/CA carbide and the support were 246 m2/g and 881 m2/g, respectively. The XRD analysis verified the presence of the Co6Mo6C2 and metallic cobalt. XPS showed the presence at the surface of signals assignable to Mod+, Mo4+, Mo6+, Co2+, S2- and SO4 2-. The sulfided CoMo/CA carbide showed higher glyceryl trioleate deoxygenation activity than the no sulfided CoMo/CA carbide. The highest yield was obtained at 310 °C, 900 psi H2 and 2 h of reaction (conversion to 100%) and a higher selectivity to heptadecane (55%) and octadecane (45%), favoring the decarboxylation (HDCX) and decarbonylation (HDCn) than the hydrodeoxygenation (HDO). [ABSTRACT FROM AUTHOR]

Impregnation solutions for the preparation of NTA-modified CoMo/Al2O3 hydrodesulfurization catalysts were prepared without use of unnecessary and disrupting NH4+ and NO3− ions. The reaction-dissolution took place in the suspension of NTA, CoCO3·xH2O and MoO3 (here DISUSPEN method). The conventional solutions, prepared in the literature using NTA, NH4OH, MoO3 and Co(NO3)2, (here DISAMON method), were neutral or basic. The solid obtained by their drying was partly crystalline. The DISUSPEN solutions were acidic, with pH = 1.0–1.5. The DISUSPEN solids were XRD-amorphous with glass-like appearance. Much less nitrogen-containing emissions is produced during in-situ sulfidation of DISUSPEN catalysts as compared with DISAMON catalysts. Catalysts prepared by the DISUSPEN method are more active in HDS of thiophene than those prepared by the conventional DISAMON method. [ABSTRACT FROM AUTHOR]

Copyright of Rudarsko-Geolosko-Naftni Zbornik is the property of Faculty of Mining, Geology & Petroleum Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The concentrations of trace elements in pyrite from blocks 8, 19-SE, 19-NW, 19-NE, 19-SW, 103-W, 103-E, 144, 146, 147, 149-south, 150, and 151 of copper-gold high sulphidation Chelopech deposit were determined by LA-ICP-MS. It was found that the pyrites from the individual blocks are enriched in different degrees of "impurity" elements: the highest contents of Ag, Au, Zn, Hg, and In are typical to block 19-NE; Se, Bi, and Ti to block 19-SE; As, Mn, Tl, V, and Cd to block 19-SW; Co and Ni to block 144; Sb and Sn to block 146; Cu to block 149-south; Pb, Te, and Ga to block 103-E and Cr to block 103-W. The obtained results also show that in collomorhic pyrites the variations in the contents of trace elements are always very large and are rather due to adsorption processes than isomorphism. In addition, pyrites are also enriched in poisonous trace elements, especially from the lower level of the northern blocks, which, however, also have the highest values of gold and silver. [ABSTRACT FROM AUTHOR]

In this study, ammonium phosphate ((NH4)3PO4) was employed to realize improvement by modifying the physical characteristics of the malachite surface, ensuring sustainable flotation throughout the flotation operations, and enhancing the flotation process to be more stable. Furthermore, various techniques, including X-ray photoelectron spectroscopy, were intensely used to investigate the configuration and physico-chemical surface characteristics through micro-flotation experiments, contact angle and zeta potential measurements, and XRD, ToF-SIMS, EPMA, and FTIR spectrum analyses. The FTIR findings showed that new characteristic peaks of -C(=S)-N.H. groups formed and adsorbed on the surfaces of malachite at 1636 cm-1. The -CH2 groups throughout the flotation process, further promoted the attachment of the CH3 ligand to the Cu2+ ion, and the XPS analysis confirmed this. Consequently, it can be concluded that (NH4)3PO4 played a substantial part in the improved recovery rate, as demonstrated and confirmed by the methods carried out in this study. Thus, it was used to modify the physical properties surface before adding Na2S to efficiently enhance malachite floatability and reduce the loss rate of malachite. Regarding the alterations in the physical characteristics which occurred to the malachite surface, and as a consequence of increasing the recovery results of flotation, the malachite sample treated initially with (NH4)3PO4 exhibited micro flotation results with a considerably greater flotation recovery than malachite treated initially with only Na2S ions. [ABSTRACT FROM AUTHOR]

The gold mineralization at the Tau deposit in northeastern Botswana can be distinguished into two stages. The first stage of mineralization consists of invisible gold associated with early, sulfur‐rich arsenopyrite (Apy1). The second stage is characterized by native gold associated with late, sulfur‐poor arsenopyrite (Apy2). This study aims to constrain the nature of the ore‐forming fluid at the Tau deposit on the basis of fluid inclusion microthermometry and arsenopyrite geothermometry. Quartz crystals closely associated with gold‐bearing sulfides (Apy1) from the host rock host three types of fluid inclusions occurring in the same assemblages: Type I, two‐phase aqueous fluid inclusions, Type II three‐phase aqueous‐carbonic fluid inclusions and Type III one‐ or two‐phase CO2‐rich fluid inclusions. Microthermometric and Raman spectroscopic studies revealed the dominance of coexisting H2O+NaCl (Type I) and CO2N2CH4 (Type III) fluid inclusions. The coexisting Type I and Type III fluid inclusions could represent products of the immiscibility of a homogenous H2OCO2NaClN2CH4 primary ore fluid. The salinity of Type I (calculated from melting temperature of ice) and Type II (calculated from dissolution temperature of clathrate) fluid inclusions vary from 3.4 to 9.2 wt% NaCl equiv. and 5.8 to 9.8 wt% NaCl equiv., respectively. The overall fluid inclusion salinity range (<10 wt% NaCl equiv.) and gas compositions of fluids suggest that the primary ore‐forming fluid at the Tau deposit was of low salinity and H2OCO2N2CH4NaCl composition. Integration of fluid inclusion microthermometry and arsenopyrite geothermometer results suggest that the first stage and second stages of gold mineralization and the associated alteration at the Tau deposit occurred at pressure and temperature conditions of 75–145 MPa and 290–370°C and 85–160 MPa and 330–370°C, respectively. These results suggest that there was an increase in temperature from the first stage to the second stage of mineralization, resulting in the recrystallization of invisible gold‐bearing arsenopyrite in the first stage to form native gold‐bearing arsenopyrite in the second stage. Fluid composition and the estimated physico‐chemical conditions at the Tau deposit confirm that gold was transported as reduced bisulfide complexes and initial gold deposition was likely caused by a reduction in sulfur contents as a result of sulfidation reactions and pressure‐induced phase separation (fluid immiscibility). [ABSTRACT FROM AUTHOR]

The Mupane gold deposit, which is one of the numerous gold occurrences in the Tati Greenstone Belt in the northeastern part of Botswana, consists of four orebodies, namely Tau, Tawana, Kwena, and Tholo deposits. The present research, which focuses on the genesis of the Tau deposit, was based on ore petrography, mineral chemistry of sulfides, and sulfur isotope data. Mineralogical characteristics of the host rocks indicate that banded iron formation at the Tau deposit includes iron oxides (magnetite), carbonates (siderite and ankerite), silicates (chlorite and amphibole), and sulfides (arsenopyrite and pyrrhotite). The deposit features arsenopyrite‐rich zones associated with biotite‐chlorite veins, which are indicative of the precipitation of arsenopyrite concomitant with potassic alteration. The replacement of magnetite by pyrrhotite in some samples suggests that sulfidation was likely the dominant gold precipitation mechanism because it is considered to have destabilized gold‐thiocomplexes in the ore‐forming fluids. Based on textural relationships and chemical composition, arsenopyrite is interpreted to reflect two generations. Arsenopyrite 1 is possibly early in origin, sieve textured with abundant inclusions of pyrrhotite. Arsenopyrite 1 was then overgrown by late arsenopyrite 2 with no porous textures and rare inclusions of pyrrhotite. Gold mineralization was initiated by focused fluid flow and sulfidation of the oxide facies banded iron formation, leading to an epigenetic gold mineralization. The mineralogical assemblages, textures, and mineral chemistry data at the Tau gold deposit revealed two‐stage gold mineralizations commencing with the deposition of invisible gold in arsenopyrite 1 followed by the later formation of native gold during hydrothermal alteration and post‐depositional recrystallization of arsenopyrite 1. Laser ablation inductively coupled plasma mass spectrometric analysis of arsenopyrite from the Tau deposit revealed that the hydrothermal event responsible for the formation of late native gold also affected the distribution of other trace elements within the grains as evidenced by varying trace elements contents in arsenopyrite 1 and arsenopyrite 2. The range of δ34S of gold‐bearing assemblages from the Tau deposit is restricted from +1.6 to +3.9‰, which is typical of Archean orogenic gold deposits and indicates that overall reduced hydrothermal conditions prevailed during the gold mineralization process at the Tau deposit. The results from this study suggest that gold mineralization involved multi‐processes such as sulfidation, metamorphism, deformation, hydrothermal alteration, and gold remobilization. [ABSTRACT FROM AUTHOR]

Rationally constructing high-performance electrocatalysts for the oxygen evolution reaction (OER) is a key step to increase the efficiency of the water electrolysis system. Herein, one-dimensional (1D) Co9S8/Co(OH)F heterostructures were constructed through in situ hydrothermal sulfidation of Co(OH)F nanobelts. The experimental results showed that crystalline Co9S8 nanoparticles can be intimately grown on the surface of Co(OH)F nanobelts to form hybrid catalysts with explicit heterointerfaces. When used as an electrocatalyst for OER, the prepared Co9S8/Co(OH)F nanohybrid affords superior OER performance and long term stability with negligible stability delay after 12 h tests in an alkaline electrolyte. According to the physicochemical characterization, the rational integration of Co(OH)F and Co9S8 at the interface leads to strong interfacial electronic interaction, which can expose abundant catalytic active sites and increase the electron transfer rate for OER. Such heterointerfaces can help in modulating the functionalities of the hybrid catalysts to boost the electrocatalytic activity towards the oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Controllable chemoselectivity and regioselectivity synthesis of 3‐sulfinylated, 3‐sulfenylated and 2‐sulfonylated indoles via direct C−H functionalization are realized under metal‐free conditions. In particular, the synthesis of 3‐arylsulfinylindoles in high yields from a sulfone substrate in water without additives is reported. The process displays excellent functional groups compatibility. p‐Toluenesulfonyl cyanide (TsCN) possesses a hexavalent sulfonyl group, as an odorless and easy‐to‐handle solid, which has been used as a new sulfur reagent through the cleavage of S−C and S=O bonds in our work. [ABSTRACT FROM AUTHOR]

[Display omitted] • Development of a fluorine-free hydrothermal method for the preparation of MoS 2 /Mo 2 CT x MXene. • Thioacetamide was used as the source of sulfide ions for the sulfidation of MXene. • Microwave-assisted hydrothermal treatment resulted in MoS 2 formation on the MXene surface. • Amorphous MoS 2 on the MXene surface enhanced its chemical stability. • MoS 2 /Mo 2 CT x exhibited superior catalytic activity for the hydrogen evolution reaction in alkaline medium. Synthesizing MXenes from M n+1 AX n (MAX) phases using hazardous hydrogen fluoride is a common and effective method. However, fluorine termination on the basal planes and edges of the resulting MXenes is undesirable for the electrocatalytic hydrogen evolution reaction (HER), while oxygen (O), hydroxyl (OH), and sulfur (S) termination favors this reaction. Herein, we unveil a simple fluorine-free exfoliation and two-step vulcanization method for synthesizing molybdenum sulfide-modified molybdenum carbide (MoS 2 /Mo 2 CT x MXene, T = OH, O, S) for the HER in alkaline medium. Microwave-assisted hydrothermal treatment of the MAX phase (Mo 3 AlC 2) with sodium hydroxide-sodium sulfide as an etching solution and thioacetamide as a source of sulfide ions enabled the selective dissolution of the aluminum (Al) layer and sulfidation of the surface Mo atoms to form amorphous MoS 2. Thus, the vulcanization of Mo 2 CT x MXene resulted in the formation of MoS 2 /Mo 2 CT x MXene. The MoS 2 formed on the surface of Mo 2 CT x provided enhanced stability by preventing oxidation. MoS 2 /Mo 2 CT x exhibited enhanced electrocatalytic activity toward the HER, mainly due to the O, OH, and amorphous MoS 2 functionalities. The MoS 2 sites on the surface exhibited an overpotential of 110 ± 7 mV at a current density of 10 mA cm−2 as a result of enhanced charge transfer and mass transfer. Thus, the sulfidation method demonstrated herein is capable of producing amorphous MoS 2 structures on Mo 2 CT x MXene, which could be applied for the surface modification of other molybdenum-based nanomaterials or electrocatalysts to improve stability and enhance electrocatalytic activity. [ABSTRACT FROM AUTHOR]

Protonation of [(Me3tacn)MoO3] with one or two equivalents of strong proton acid afforded mono‐protonated complex [(Me3tacn)MoVIO2(OH)](CF3SO3) and bi‐protonated complex [(Me3tacn)MoVIO(OH)2](PF6)2, respectively. Sulfidation with iPr2NCS2Na or CS2 in acetonitrile, followed by in situ protonation of [(Me3tacn)MO3] (M=Mo, W), produced two monomeric complexes [(Me3tacn)MoVIO2S] ⋅ (iPr2NH2) ⋅ (PF6) ⋅ CH2Cl2 and [(Me3tacn)WVIO2S], and two dimeric complexes [(Me3tacn)MoVO(μ‐S)2MoVO(κ2‐S2C=O)] ⋅ CH3CN and [(Me3tacn)MoIVO]2(μ‐O)(μ‐S2) ⋅ 2DMF. The crystal structures of the two protonated molybdenum(VI) complexes and the four oxo‐sulfido molybdenum/tungsten complexes have been determined. Moreover, the complexes have been characterized by infrared, Raman, fluorescence and UV‐vis spectroscopies. (Me3tacn=1,4,7‐trimethyl‐1,4,7‐triazacyclonane). [ABSTRACT FROM AUTHOR]

The Ruwai skarn deposit is located in the Schwaner Mountain complex within the central Borneo gold belt and is currently considered the largest Zn skarn deposit in Indonesia. The deposit has been known to host Zn-Pb-Ag mineralization in the form of massive sulfide ore bodies; however, the occurrence of Ag-bearing minerals has not been identified yet. This study documents the mineralogical characteristics of several Bi-Ag sulfosalts and sulfoarsenides, as well as their chemical compositions. Ten Bi-Ag sulfosalts were identified, including native bismuth, tetrahedrite, cossalite, tsumoite, bismuthinite, joseite-B, Bi6Te2S, Bi-Pb-Te-S, Bi-Ag-S, and Bi-Te-Ag. Three sulfoarsenides were identified, including arsenopyrite, glaucodot, and alloclasite. The occurrence of Bi-Ag sulfosalts is typically associated with massive sulfide mineralization, although tsumoite can also be found associated with massive magnetite. In terms of sulfoarsenides, both arsenopyrite and glaucodot are associated with massive sulfide mineralization, whereas alloclasite is associated with massive magnetite mineralization. The Bi-bearing minerals are characterized by irregular, bleb-like texture or patch morphology, and occur either as free grains or inclusions within sulfides, such as galena or pyrite. Tetrahedrite typically has an anhedral shape with a rim or atoll texture surrounding sphalerite or galena. In contrast, sulfoarsenides are typically found as euhedral–subhedral grains where glaucodot typically is rimmed by arsenopyrite. Both Bi-Ag sulfosalt and sulfoarsenides were formed during the retrograde stage under high oxidation and a low sulfidation state condition. The ore-forming temperature based on arsenopyrite geothermometry ranges from 428 °C to 493 °C. [ABSTRACT FROM AUTHOR]

The activity and selectivity of sulfidized and non- sulfidized palladium alumina supported catalysts in the hydrogenation of 1,3-pentadiene to pentenes is studied. Preliminary sulfidation of palladium catalysts substantially improves their selectivity toward olefins in a broad range of Н2 : diene ratios (from 2.5 to 10). Samples activated in Н2 at elevated temperatures display higher activity in diene hydrogenation. Palladium catalysts are more active at low temperatures of the reaction, but sulfidized Ni catalysts studied earlier are competitive with palladium ones in selectivity toward olefins and productivity, and are more selective in an excess of hydrogen. The modification of palladium with chromium, silver, or lithium improves the selectivity toward olefin. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) as self-sacrificing templates for high-performance supercapacitor electrode materials have garnered significant attention. In this study, the core-shell multi-heterojunction array of NiCo-LDH@NiCoS@NiMnS was synthesized for the first time using a NiCo-MOF template through hydrothermal growth, followed by ion substitution etching and controlled sulfidation. The NiCo-LDH@NiCoS@NiMnS core-shell multi-heterojunction boasts a hierarchically porous framework, multi-component synergy, and robust structural stability, which together provide abundant redox active sites and facilitate rapid reaction kinetics. Consequently, the self-supporting NiCo-LDH@NiCoS@NiMnS porous electrode achieves a specific capacitance of 9.31 F cm−2 (1862 F g−1) at 8 mA cm−2 (1.6 A g−1) and demonstrates excellent rate performance (52 %, 8–50 mA cm−2). The assembled NiCo-LDH@NiCoS@NiMnS//AC asymmetric supercapacitor (ASC) exhibits an energy density of 88.9 Wh kg−1 at 323.5 W kg−1, maintaining an energy density of 49.7 Wh kg−1 even at a power density of 4043 W kg−1. It retains 90 % of its capacitance after 6000 cycles at 16 mA cm−1. Notably, two ASC devices in series can power an LED light for over 30 minutes. These results confirm that the MOF self-sacrificing template method and controllable sulfidation strategy are effective for designing electrode structures in electrochemical energy storage. [Display omitted] • The NiCo-LDH@NiCoS@NiMnS core-shell multiple heterojunctions array electrodes are synthesized. • The porous heterojunction framework shows good structural stability and fast reaction kinetics. • The synergistic effect between the multi-components improves the energy storage performance. • A hybrid supercapacitor delivers an energy of 49.7 Wh kg−1 at 4043 W kg−1. [ABSTRACT FROM AUTHOR]

• Selective sulfidation of nickel can be achieved under appropriate pO 2 and pS 2. • Appropriate carbon can facilitate the conversion of nickel oxide to nickel sulfide. • Sodium carbonate can improve the growth of synthetic Fe-Ni-S particles. • Under optimal conditions, 85.7% of Ni and only 27.1% of Fe in laterites could be sulfated. Nickel sulfide concentrate was an important raw material for battery-grade nickel sulfate. To efficiently separate nickel from saprolitic laterite to product nickel sulfide concentrate, a novel and clean sulfidation-flotation process aimed to enhance selective sulfidation and particle growth through sodium carbonate was proposed herein. The effects of temperature, time, sulfur dosage, Na salts, and carbon additions on the selective sulfidation of nickel are systematically studied. Experimental results show that sodium carbonate can destroy the silicate structure, release nickel in the silicate, and form a low-melting point phase, promoting the aggregation of nickel sulfide, thereby achieving the purpose of promoting the sulfidation of nickel and the growth of synthetic nickel matte particles. Under the optimal conditions, 85.7% Ni and 27.1% Fe could be sulfated. [ABSTRACT FROM AUTHOR]

[Display omitted] This paper focused on the catalytic sulfidation of hemimorphite to examine the promotional effect of NH 4 Cl on surface sulfidation and its impact on the flotation performance. The interaction mechanism between NH 4 Cl and the hemimorphite surface in the sulfidation flotation system was clarified. Micro-flotation tests were conducted using the sulfidation-xanthate flotation method. Compared with direct sulfidation, adding 2.5 × 10−4 M ammonium chloride to the flotation system increased the maximum flotation recovery of hemimorphite by about 18 %. AFM and SEM-EDS analysis revealed that NH 4 Cl dissolved the hemimorphite surface and destroyed its structure. This exposed more Zn sites and enhanced the sulfidation of the hemimorphite surface. FTIR spectroscopy indicated that adding NH 4 Cl promoted the adsorption of xanthate components on the hemimorphite surface, which formed more hydrophobic substances. XPS analysis of the hemimorphite surface suggested that NH 4 Cl complexed with Zn species on the hemimorphite surface, which enhanced the reactivity of HS− and S2−, thus improving the floatability. Further ToF-SIMS analysis confirmed that catalytic sulfidation produced a thicker and denser ZnS layer on the hemimorphite surface. Its surface activity was superior to that obtained by direct sulfidation, showing that NH 4 Cl improved sulfidation flotation performance of hemimorphite. DFT results confirmed that catalytic sulfidation can occur spontaneously·NH 3 species separated from the hemimorphite surface and returned to the solution, and stable Zn-S covalent bonds were formed on the hemimorphite surface. These results provide a potential method for promoting the recovery of zinc oxide minerals. [ABSTRACT FROM AUTHOR]

[Display omitted] • MoS 2 -based catalysts with tunable structure was designed for HAS. • The sulfidation and morphology of MoS 2 slabs can be precisely modulated by CTAB. • Dominant double-layer MoS 2 stacking (∼39.1 %) and proper slab length was achieved. • KNiMoS/MgAl-0.1 exhibited high C 2+ OH selectivity (75 %) and C 2+ OH STY (63 mg g-1h−1). Higher alcohols synthesis (HAS) via CO hydrogenation demonstrates the promising demands and application prospect, in which the C–C chain growth and CO insertion are highly crucial to obtain high CO conversion and high alcohols selectivity but remain great challengable. Rational metal-support interaction plays vital role to regulate the morphology of MoS 2 slabs on Mo-based sulfided catalysts for promoting the C–C chain growth and CO insertion in HAS process. Herein, a series of MgAl oxides supported KNiMoS catalysts (KNiMoS/MgAl-x) with controllable microstructure were fabricated via cetriltrimethylammonium bromide (CTAB)-assisted hydrothermal combined with incipient wetness impregnation methods. Experimental results and material characterizations demonstrated that the appropriate metal-support interaction with CTAB assistance can enable the high sulfidation degree of catalyst and high dispersion of MoS 2 slabs to expose more edge active sites. Moreover, the suitable stacking degree with the highest ratio of double-layer MoS 2 slabs can further promote the alcohol formation in HAS. And as a result, the optimal KNiMoS/MgAl-0.1 exhibits the superior alcohols selectivity of 65.1 %, C 2+ OH proportion of 75 % and C 2+ OH space–time yield of 63.0 mg g cat -1h−1. The dependence of HAS performance on MoS 2 active phase structure was also demonstrated to get insight into the structure-performance relationship. This work proposes a novel strategy to design high-efficiency MoS 2 -based catalysts for HAS via precisely controlling the dispersion and stacking degree of MoS 2 slabs through regulating metal-support interaction with surfactant assistance. [ABSTRACT FROM AUTHOR]

One of the main challenges for oxygen evolution reaction (OER) is to develop electrocatalysts with high performance, suitable stability, and low cost. First-row transition metal compounds have received attention due to their high electrocatalytic activity and diverse electronic structure. Meanwhile, metal-organic frameworks (MOFs) have emerged as promising alternative for OER due to their porous structure and unsaturated metal sites. In this study, FeCoNi-MOF based on MIL-88B was synthesized by a hydrothermal method. Then, the performance of the catalyst was investigated and improved by calcination and sulfidation at three temperatures of 250 ℃, 350 ℃, and 450 ℃. The phase development and crystal structure parameters of the synthesized samples were confirmed through X-ray diffraction. Additionally, the intensity of the peaks increased with the rise in calcination temperature. Field emission scanning electron microscopy revealed well-defined and uniformly distributed nanorods and nanospheres particles of calcinated and sulfides samples. The weight percentage (wt%) of the elements in the samples were verified to align with their stoichiometric ratios. The synthesized catalysts were loaded onto a nickel foam by a one-step method, and their electrocatalytic properties were examined in the OER process in 1.0 M KOH alkaline solution. The (FeCoNi)-O250 ℃ electrocatalyst, maintaining its nanorod morphology, exhibited an overpotential of 313 mV at a current density of 10 mA.cm-² and a small, stable Tafel slope of 31.5 mV.dec−1 and good charge transfer of 0.73 mF. Cm−2. However, the (FeCoNi)-S250 ℃ electrocatalyst showed better performance in the OER process with an overpotential of 298 mV at a current density of 10 mA.cm-² and a small and stable Tafel slope of 29 mV.dec−1 and good charge transfer of 0.82 mF. Cm−2. In other words, a higher Cdl increased reaction rates or lower overpotentials required for the reaction to occur. Furthermore, the activity of this catalyst remained constant at a fixed current density of 10 mA.cm-² for 18 hours. Based on the electron microscopy observations, and electrochemical evaluations, this superior performance can be attributed to the morphological change from nanorods to porous nanospheres due to sulfidation, resulting in increased electrochemically active sites and decreased charge transfer resistance. [Display omitted] • High efficient electrocatalytic water oxidation based on non-precious metal oxides/sulfides. • The performance of the catalysts were explored and improved by calcination and sulfidation at various temperatures • The (FeCoNi)-S250 ℃ electrocatalyst showed the best performance with an overpotential of 298 mV (at 10 mA.cm-²). • A small and stable Tafel slope of 29 mV.dec−1 and good charge transfer of 0.82 mF. Cm−2 was obtained. • The activity of (FeCoNi)-S250 was remained constant at a fixed current density of 10 mA.cm-² for 18 h. [ABSTRACT FROM AUTHOR]

• ReMoS x @HSSZ-39 is prepared with ReMoS x clusters uniformly anchored in cages of HSSZ-39 zeolite. • Cooperation between ReMoS x clusters and zeolitic acids constitutes intimate bifunctional catalyst. • ReMoS x @HSSZ-39 shows high-performance for CO 2 hydrogenation to C 2-4 hydrocarbons. • ReMoS x @HSSZ-39 mixed with SAPO-34 shows further promoted performance and stability. We report here a high-performance catalyst ReMoS x @HSSZ-39 compounded with SAPO-34 for conversion of CO 2 to C 2-4 hydrocarbons, in which the ReMoS x clusters are responsible for highly efficient hydrogenation of CO 2 to methanol as the intermediate and then the surrounding zeolitic acid sites for further conversion of methanol to hydrocarbons. The investigation finds that uniform ReMoS x clusters can be reliably fabricated in zeolitic cages by co-introduction of rhenium and molybdenum species into the HSSZ-39 zeolite and followed by sulfidation, which constitutes an intimate bifunction catalyst through better cooperation of ReMoS x clusters and the zeolitic acid sites. Compared with MoS x @HSSZ-39, the introduction of rhenium significantly suppresses CO generation. By mixing some SAPO-34 zeolite, with increased density of protonic acid, more than 86 % C 2-4 hydrocarbons in organic products and only 21 % CO at 32.5 % of CO 2 conversion are obtained and the composite catalyst shows excellent stability with more than 95 % C 2-4 hydrocarbons in organic products, less than 30 % CO and above 26.6 % of CO 2 conversion after 1000 h on stream. [ABSTRACT FROM AUTHOR]

The sulfide precipitation has been widely used to recover Cu(II) and remove As(V) in copper smelting electrolyte based on the Cu(II)-As(V) separation. However, the recovery efficiency was undesirable due to the inaccurate control of process parameters. It was necessary to investigate the process and mechanisms of sulfurization precipitation for accurate adjustment. Herein, under the single and mixed solutions of Cu(II) and As(V), the process parameters were investigated and the precipitation mechanisms were explored. And when using actual electrolytes, the corresponding sulfurization process and mechanisms were also revealed. The sulfurization results of single component solutions suggested that Cu(II) was rapidly precipitated in one step, but As(V) firstly generated intermediate, then it was gradually reduced to As(III) for a longer time and quickly precipitated in the form of amorphous. This phenomenon caused the significantly faster removal speed of Cu(II) than that of As(V). For their mixed solutions, only a small amount of As(V) were removed by adsorbing the precipitate at the low S/Cu molar ratios (R S/Cu), and Cu(II) and As(V) could achieve a good separation. Simultaneously, it revealed that the sulfidation competitive mechanisms were related to the solubility product constant (Ksp) and initial As(V) concentrations. In addition, the similar rules were also observed in actual electrolytes. Moreover, under R S/Cu = 1.2 and reaction time of 10 min, the arsenic content of sulfide precipitates in the actual electrolyte was less than 2.5%, which showed a great separation also could be obtained for the actual electrolyte. This result met the requirement of Cu(II) recovery. It can provide a good reference for adjusting sulfidation parameters in the actual process to achieve efficient copper recovery, reduce the production of hazardous waste containing arsenic at the source and realize the cleaner production of copper smelting system. [Display omitted] • The removal speed of As(V) was greatly slower than that of Cu(II) in sulfidation. • The conversion of H 3 AsO 3 S was influenced by the R S/As and reaction temperature. • The Cu(II)-As(V) separation mechanism in sulfurization was revealed. • The Cu(II)-As(V) competitive mechanism in sulfidation was revealed. • As Content in CuS slag obtained in actual copper electrolyte was less than 2.5%. [ABSTRACT FROM AUTHOR]

The Marifil Complex constitutes the early stage of the Chon Aike Igneous Province along eastern North Patagonia, Argentina. Geological, geochronological, and geochemical data indicate that this magmatism consists of two characteristic Lower Jurassic volcanic events (V0 and V1). The epithermal activity takes place in V1 as Au-Ag veins (Pavón Pivetta et al., 2024). Particularly, base metal veins are covered and masked by the important explosive volcanic activity related to the V1 volcanic stage. This makes geophysical exploration a highly recommended tool for interpreting subsurface geological features. With this in mind, we have carried out the acquisition and processing of gravity and magnetic data that is supported with drill holes and geochronological data. A series of gravity and magnetic highs and lows were recognized, together with major lineaments. Using Euler deconvolution, the depth of the sources that generate the anomalies was calculated. The analysis of these results allowed us to construct two perpendicular gravity 2D models for the calculation of thicknesses and depth of the rhyolitic coulée. The gravity lows were associated with the major thickness of rhyolitic coulée , reaching 290 m in the drill holes, and interpreted geophysically to have a deeper root. The gravity highs were interpreted in two possible ways: a basement depth decrease and/or the absence of the rhyolitic coulée. The minimum depth estimated for the basement highs is approximately 20 m. These interpretations are consistent with outcrop, drill hole and geochronologic data, and magnetic maps. The RMSE between the calculated and the observed anomalies of the models are about 0.316 and 0.519 mGal. Due to the shape of the anomalies obtained from the gravimetric maps, the structures that generate the anomalies were considered as generated by three-dimensional bodies. For this purpose, we created a 3D model that provides interesting data about the possible location of these non-outcropping gravity lows that are located in the first 200 m depth. These results demonstrate that the use of the gravity and magnetic method constitutes a useful, fast, economical, robust, and reliable tool for the identification of these volcanic structures. • Low sulphidation Geophysical exploration in the Nort Patagonian region. • Jurassic Volcanism and U- dating in epithermal veins. • 2D and 3D gravity modelling in Arroyo Verde mining Project. • Geophysical prospecting of epithermal veins. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel method for preferential recovery of lithium from spent LiCoO 2 cathode material. • Achieving the final recovery rate of lithium over 99% and without generating toxic gas or wastewater. • Compared to mainstream recycling processes, the comprehensive lithium recovery rate has increased by about 20%. • It is an environment-friendly and cost-effective method for preferential recovery of lithium. Due to the needs of protecting the environment and recycling resources, the extraction of lithium from spent lithium-ion batteries has become increasingly important. Different from the traditional roasting process, a novel approach for the selective recovery of lithium from spent LiCoO 2 (SLCO) through low-temperature sulfidation roasting was proposed in the present work. The thermodynamics of the sulfidation roasting was investigated and phase transformation was detected. The results showed that the S 2 gas generated from the decomposition of pyrite converted LiCoO 2 into Li 2 SO 4 and cobalt sulfides. Under optimal experimental conditions, lithium can be selectively leached with a yield of more than 99% through water immersion treatment, resulting in around 20% improvement in the overall recovery rate of the metal compared to current industrial practices. The thermochemical process did not produce toxic SO x gases, whereas the selective leaching process for lithium did not require additional reagents, resulting in good environmental and economic benefits. [ABSTRACT FROM AUTHOR]

In this study, sulfide-modified zero-valent iron (S-ZVI) synthesized by a two-step process with optimal S/Fe ratio of 0.056 was used to activate hydrogen peroxide (H 2 O 2) to degrade phenol, and the kinetics and reaction mechanism of phenol degradation were investigated under different conditions. Phenol degradation kinetics in S-ZVI/H 2 O 2 system was characterized by an initial lag phase followed by a rapid reaction period, which was accurately described by Logistic regression model, deviating from conventional pseudo-first-order and pseudo-second-order models. Over 80 % of phenol degradation occurred via liquid-phase reactions, predominantly driven by hydroxyl radicals (•OH). The consumption of H 2 O 2 and the removal of total organic carbon (TOC) were both significantly correlated with the total dissolved iron content, underscoring the importance of iron dissolution. The S-ZVI/H 2 O 2 system outperformed other activated H 2 O 2 systems, with a 41.71 %, 35.89 %, and 44.02 % increase in H 2 O 2 utilization efficiency for TOC removal compared to FeSO 4 , ZVI, and ZVI(H+), respectively. Sulfide-modification of ZVI significantly promoted the sustained release of dissolved iron with a higher proportion of Fe2+, which was identified as a key factor in enhancing H 2 O 2 utilization efficiency. Our findings provide new insight into a better description of the pollutant removal kinetics process in the S-ZVI/H 2 O 2 system and the synergistic effects between S-ZVI and H 2 O 2 for organic pollutant degradation. [Display omitted] • Phenol degradation kinetics were accurately described by Logistic model. • S-ZVI/H2O2 significantly improved TOC removal and H2O2 utilization efficiency. • S-ZVI serves as a slow-release iron source and greatly promoted the conversion of Fe3+ to Fe2+. • H2O2 residue and TOC removal were significantly correlated with the total dissolved iron content. • The solution reaction contributed over 80 % to phenol degradation in S-ZVI/H2O2 system. [ABSTRACT FROM AUTHOR]