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This study developed a new method for in situ measurement of stable Mo isotope ratio using femtosecond laser ablation connected to a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS). We assessed how laser fluence, laser repetition rate, and signal intensity impact Mo isotope mass fractionation, using synthetic molybdenite Mo-H8 as the reference material. Findings reveal that the laser repetition rate has negligible impact on Mo isotope fractionation, while signal intensity and laser fluence slightly influence the precision of d98Mo. Significant signal intensity disparities between samples and reference materials can markedly affect the results of Mo isotopes. We analyzed natural molybdenite samples from various deposits in China with this new method, with the optimal laser parameters including a repetition rate of 10 Hz, a spot size of 20 mm, and a fluence of 1 J cm-2. The d98MoNIST SRM 3134 values for nine natural samples (GD-1, GD-2, YN-1, YN-2, YN-3, SX-1, SX-2, SX-3, and GX-1) align with those obtained by solution nebulization MC-ICP-MS within analytical uncertainty, demonstrating the accuracy of this new in situ Mo isotope analytical method. This new technique offers a reliable alternative to solution nebulization MC-ICP-MS in bulk analysis, enabling precise detection of Mo isotope ratio variations at a finer scale, which provides valuable insights into mineralization processes. [ABSTRACT FROM AUTHOR]

The East Qinling Molybdenum Belt (EQMB), which is located on the southern margin of the North China Craton (NCC), is the largest Mo province in the world. This belt hosts a significant number of Mesozoic magmatic-hydrothermal Mo deposits and a small portion of pre-Mesozoic Mo deposits. Understanding the mineralization timing and mechanism of the unique pre-Mesozoic Mo deposits is essential to comprehend the evolution of the EQMB, the pre-Mesozoic Mo enrichment, and the Mesozoic Mo mineralization event. The recently discovered Zhaiwa deposit is a porphyry Mo deposit located in the Xiong'er Terrane of the EQMB. In this study, five molybdenite samples from the Mo-bearing quartz veins were analyzed for Re-Os isotopes composition. These samples yield an isochron age of 1794 ± 45 Ma, which represents the age of mineralization. The mineralization is mostly hosted within the biotite-amphibole plagiogneiss and granite porphyry. LA-ICP-MS U-Pb data of zircons constrain the crystallization age of the granite porphyry to be at 1791 ± 16 Ma. The close spatial and temporal association suggests that the granite porphyry is the causative rocks of the Mo mineralization. The δ34S values of pyrite vary from 5.3 to 6.8‰, suggesting that the S was mainly derived from magmatic source. The intrusion of magmas and associated Mo mineralization are contemporaneous to the regional Xiong'er volcanism that occurred during the late Paleoproterozoic. The Xiong'er volcanism was triggered by partial melting of lithospheric mantle in an extensional setting. The results of our study provide robust evidence for a late Paleoproterozoic Mo metallogenic event along the southern margin of the NCC. Future exploration should also consider the potential of late Paleoproterozoic porphyry Mo mineralization existing in the EQMB, which is closely associated with the Xiong'er volcanism. [ABSTRACT FROM AUTHOR]

The inhibiting mechanism of high pH on the molybdenite flotation was studied using an experimental and DFT method. The experimental results found that adverse effects of pH on molybdenite flotation should be attributed to the adsorption of OH− on molybdenite [100] surface (MS100). The DFT results show the adsorption energy of H2O/OH− to molybdenite [001] surface (MS001) and MS100 is −8.61/288.30 kJ·mol−1 and −226.81/−302.44 kJ·mol−1. These indicate that H2O is weakly adsorbed on MS001, while OH− is not. Both H2O and OH− can be adsorbed onto MS100. The adsorption energy of OH− to MS100 is much stronger than that of H2O. The results of state density and charge transfer of the adsorption of OH− on MS100 further show that OH− can be chemically adsorbed on MS100 through the bonding of the O atom of OH− and the Mo atom of MS100. This causes a significant reduction in the MS100 hydrophobicity and deteriorates the fine molybdenite flotation. [ABSTRACT FROM AUTHOR]

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office 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.)

This research mainly investigated the flotation kinetics of molybdenite in seawater based on four flotation models. Molybdenite flotation presented an excellent agreement with the first-order model with rectangular distribution. The ultimate cumulative recovery (R∞) and flotation rate constant (k) of molybdenite decreased in seawater, mainly due to the divalent cations, with the impact of Mg2+ being significantly greater than that of Ca2+. The addition of sodium silicate (SS) and sodium hexametaphosphate (SH) increased the flotation recovery and rate, probably due to the positive role of dispersants on preventing the attachment of seawater precipitates onto molybdenite surface. In addition, three different stages of flotation kinetics were proposed to reveal the molybdenite flotation for the first time, with the highest flotation recovery and rate being found at Stage I. However, seawater showed a negative role on Stage I, i.e. resulting in a longer duration and lower recovery, as compared to that in pure water. The addition of both SS and SH improved the flotation kinetics at Stage I, with SH being more significant. Therefore, it is more feasible to eliminate the negative effects of seawater on molybdenite flotation at the initial stage (Stage I). [ABSTRACT FROM AUTHOR]

The Kirazlı deposit is located at the center of the Biga Peninsula metallogenic province, in a geological setting characterized by an extensional tectonic environment. A NNW-SSE trending high-sulfidation (HS) orebody with a total reserve of 33.86 Mt @ 0.69 g/t Au and 9.42 g/t Ag lies beneath the Kirazlı Main zone. A porphyry Cu orebody hosted by Eocene intrusive and volcanic rocks has been intersected by drilling within its vicinity. The HS epithermal deposit is hosted by a partly silicified and brecciated Oligocene volcanic and volcaniclastic sequence consisting mainly of basaltic andesite lava flow and lithic/crystal tuff. Lithogeochemistry and zircon U-Pb radiometric ages allow us to distinguish three distinct high-K calc-alkaline magmatic events at ca. 41, 38, and 32 Ma, sourced by metasomatized mantle melts, which have interacted with the crust during their ascent. Porphyry Cu mineralization took place at 36.7 ± 0.4 Ma (muscovite 40Ar/39Ar age) with subsequent re-opening and base metal deposition. Crosscutting quartz-pyrite-molybdenite veins were emplaced at 33.6 ± 0.2 Ma (molybdenite Re-Os age), and followed by the HS epithermal Au-Ag event at ca. 31 Ma, based on a previous study. Our radiometric data indicate that the Kirazlı deposit has recorded a long-lasting Cenozoic magmatic and metallogenic evolution during about 10 Myr. Our study demonstrates that successive, independent, and overprinting, but genetically unrelated, HS epithermal precious metal, hydrothermal Mo, base metal, and porphyry Cu systems have been active at the same location during protracted extensional tectonics of the Biga Peninsula. [ABSTRACT FROM AUTHOR]

Analyzing sulfur (S) and molybdenum (Mo) isotope ratios in molybdenite, the most common sulfide mineral, is crucial for studying the genesis of ore deposits. However, it is necessary to prepare matrix-matched reference materials for molybdenite. In this study, we employed two different techniques, the high-temperature-high-pressure (HTHP) technique and the rapid hot-pressing technique, to synthesize molybdenites and assessed their suitability as reference materials for in situ Mo and S isotope analysis in molybdenite. The molybdenites synthesized through HTHP and rapid hot-pressing exhibit smooth surfaces and dense structures, making them suitable as reference materials for in situ Mo and S isotope analysis, respectively. These synthesized molybdenites exhibit homogeneous Mo and S isotope compositions based on a large number of LA-MC-ICP-MS measurements. The mean δ98MoNIST SRM 3134 values of 0.70 ± 0.06‰ (n = 4, 2SD) and 0.70 ± 0.05‰ (n = 4, 2SD) determined by solution nebulization MC-ICP-MS are suggested as recommended δ98Mo/95Mo values for Mo-H8 and Mo-P. The mean δ34SV-CDT value of −0.22 ± 0.10‰ (n = 9, 2SD) determined by elemental analyzer isotope ratio mass spectrometry (EA-IRMS) is suggested as a recommended δ34S/32S value for Mo-H8 and Mo-P. Therefore, we recommend combining ultrafine powders with a high-temperature–high-pressure technique and/or a rapid hot-pressing technique to synthesize reference materials for isotopic analysis of other minerals. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office 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.)

Re‐Os isotope‐dilution geochronology has been widely used to date the timing of molybdenite, pyrite and chalcopyrite formation across a variety of geological settings. However, in situ methods have been impeded by the isobaric interference of 187Re on 187Os. In situ Re‐Os geochronology using LA‐ICP‐MS/MS has been shown to be a useful technique to chemically separate Os from Re, as Os reacts with CH4 to create higher‐mass reaction products, which can then be measured with minimised interference of 187Re. However, application of the method requires matrix‐matched primary reference materials, e.g., age‐homogenous molybdenite amenable to laser ablation. Here, we characterise and present two new molybdenite mineral reference materials for in situ Re‐Os geochronology by LA‐ICP‐MS/MS, verified by ID‐TIMS Re‐Os measurements. We also present case studies from molybdenite samples with varying Re mass fractions and Re‐Os age mapping. The method provides accurate and precise age data, with excellent precision for high Re samples. The benefits of the LA‐ICP‐MS/MS approach include: (1) simple sample preparation, (2) rapid data acquisition, (3) targeting of specific textural domains including growth zones and (4) the ability to simultaneously collect trace elements used to link the timing and conditions of ore‐formation. [ABSTRACT FROM AUTHOR]

This article, published in Chemical Communications, explores the electrochemical reduction of CO2 on molybdenite (MoS2) electrocatalysts. The study utilizes scanning electrochemical cell microscopy (SECCM) to directly observe the activity of different surface structures of MoS2 in reducing CO2. The findings reveal that nanoscale defects, particularly those with exposed edge planes, demonstrate higher overall activity in CO2 reduction compared to the relatively inactive basal plane. This research offers valuable insights for the development of cost-effective electrocatalysts for large-scale CO2 electrolysis. The study focuses on the electrochemical reduction of carbon dioxide (CO2) on 2H-MoS2 using scanning electrochemical cell microscopy (SECCM). It investigates the impact of various structural features, such as creases, step edges, and nanoflakes, on the electrocatalytic activity of 2H-MoS2. The results indicate that creases and step edges exhibit enhanced CO2 reduction activity compared to the bulk material, while nanoflakes are highly active but not selective for CO2 reduction. These findings contribute to our understanding of the structure-activity relationships of 2H-MoS2 in CO2 electroreduction. [Extracted from the article]

Copyright of Uzbek Chemical Journal / O'Zbekiston Kimyo Jurnali is the property of Institute of General & Inorganic Chemistry of Academy of Sciences of Republic of Uzbekistan 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 flotation of unoxidized and oxidized molybdenite fines is a challenging job worldwide. In this work, dodecylamine (DDA) was developed as a potential collector to improve the flotation of molybdenite fines with and without oxidation. The flotation behaviors and interaction mechanisms were probed through flotation tests, contact angle, Zeta potential, Scanning Electron Microscope-Energy Dispersive Spectrometer(SEM-EDS), and X-ray Photoelectron Spectroscopy (XPS). The flotation tests revealed that DDA improved the flotation of unoxidized or oxidized molybdenite fines efficiently. The results of Zeta potential, contact angle, and SEM-EDS uncovered that a substantial number of DDA species adsorbed on both fresh and oxidized molybdenite faces and edges, thus enhancing their hydrophobicity. XPS analysis further manifested that RNH2 and RNH3+ adsorbed on the S atoms of fresh faces through hydrogen bonding. Meanwhile, RNH2 and RNH3+ mainly adsorbed on fresh edges via chemical bonding between amine groups and Mo sites and electrostatic force. For oxidized molybdenite, RNH2 and RNH3+ interacted with oxidized faces through hydrogen bonding while adsorbed on oxidized edges via hydrogen bonding and electrostatic interaction. [ABSTRACT FROM AUTHOR]

Copyright of Gold (1001-1277) is the property of Gold Magazine Editorial Office 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.)

A new method for the preparation of hydrodesulfurization catalysts based on the mechanochemical treatment of molybdenum under cryogenic conditions was proposed. The results of direct one-stage mechanochemical grinding of molybdenum at 77 K in gaseous media of He and H2 and in liquid N2, as well as in the presence of solid Ar, are reported. The physicochemical properties of the cryopowders and their catalytic activity in the model hydrodesulfurization reactions of dibenzothiophene and diesel fraction were examined. [ABSTRACT FROM AUTHOR]

In the flotation separation process of a Cu-Mo-W polymetallic ore, the wastewater from the scheelite cleaning flowsheet contains large numbers of residual flocculants and metal ions, and the separation of chalcopyrite and molybdenite requires a large number of environmentally harmful depressants. Therefore, it is necessary to find new methods to reduce the environmental and cost pressures of wastewater treatment and the use of depressants. In this work, the flotation wastewater from the scheelite cleaning flowsheet for the separation of chalcopyrite and molybdenite by selective surface passivation was investigated for the first time. Flotations of single minerals and artificially mixed minerals with or without immersion pretreatment in the presence and absence of aeration were performed. The results showed that pulp pH had no effect on the flotation of either mineral, and a molybdenite recovery of 93.22% with a chalcopyrite recovery of 10.77% was achieved under the conditions of 10 days of immersion pretreatment with aeration, 350 mg/L of kerosene, and 100 mg/L of MIBC. By combining the electrochemical cyclic voltammetry analysis and characterization by XRD and SEM, the selective surface passivation mechanism of chalcopyrite was discussed, which could be due to the coverage of the insoluble oxidation products, especially jarosite. This work has simultaneously achieved the depressant-free flotation separation of molybdenite and chalcopyrite and the reuse of scheelite flotation wastewater, which is of great significance for environmental protection and cost saving. [ABSTRACT FROM AUTHOR]

The depression of pyrite in the flotation separation of molybdenum-sulfur (Mo-S) mixed concentrate has become a significant issue. This study aimed to examine the process of separating molybdenite and pyrite in the presence of sodium humate (NaHA). The results of micro-flotation tests indicated that NaHA exhibited significant pyrite depression capabilities and displayed remarkable selectivity toward both pyrite and molybdenite. Real ore flotation experiments have shown that adding 22.5 mg/L of NaHA to the pulp of Mo-S mixed concentrate at a pH of 6.5, the flotation indexes achieved 46.01% Mo grade and 90.11% Mo recovery. It is noteworthy that the dosage of NaHA was significantly lower compared to the 505 utilized in the mineral processing plant. Contact angle measurements revealed that NaHA effectively increased the surface hydrophilicity of pyrite. Adsorption amount measurements, zeta potential measurements, and Fourier infrared spectroscopic (FT-IR) analysis indicated that the adsorption capacity of NaHA on pyrite was higher than on molybdenite. NaHA had a highly selective inhibitory capacity for Mo-S mixed concentrate and is an ideal separation depressant. [ABSTRACT FROM AUTHOR]

The leaching of molybdenum from molybdenite by oxygen pressure water leaching method was studied. The effects of ore size, oxygen partial pressure, temperature and stirring speed on oxidation of molybdenite were investigated, and the distribution of oxidation products in solid and liquid phases was discussed. The results show that the oxidation of molybdenite can be promoted by the decrease of ore particle size and the increase of oxygen partial pressure, temperature and stirring speed. The oxidation products first enter the liquid phase. When the liquid phase is saturated with MoO42-, the oxidation products will enter the slag phase in the form of MoO3. The oxidation of molybdenum during oxygen pressure water leaching of molybdenite can be described by the unreacted nuclear shrinkage model. The reaction rate is controlled by the mixed control model, and the apparent activation energy is 40. 55 kJ/mol. [ABSTRACT FROM AUTHOR]

The Dahongshan Fe‐Cu (‐Au) deposit is a superlarge deposit in the Kangdian metallogenic belt, southwestern China, comprising approximately 458 Mt of Fe ores (40% Fe) and 1.35 Mt Cu. Two main types of Fe‐Cu (‐Au) mineralization are present in the Dahongshan deposit: (1) early submarine volcanic exhalation and sedimentary mineralization characterized by strata‐bound fine‐grained magnetite and banded Fe‐Cu sulfide (pyrite and chalcopyrite) hosted in the Na‐rich metavolcanic rocks; (2) late hydrothermal (‐vein) type mineralization characterized by Fe‐Cu sulfide veins in the hosted strata or massive coarse‐grained magnetite orebodies controlled by faults. While previous studies have focused primarily on the early submarine volcanic and sedimentary mineralization of the deposit, data related to late hydrothermal mineralization is lacking. In order to establish the metallogenic age and ore‐forming material source of the late hydrothermal (‐vein) type mineralization, this paper reports the Re‐Os dating of molybdenite from the late hydrothermal vein Fe‐Cu orebody and H, O, S, and Pb isotopic compositions of the hydrothermal quartz‐sulfide veins. The primary aim of this study was to establish the metallogenic age and ore‐forming material source of the hydrothermal type orebody. Results show that the molybdenite separated from quartz‐sulfide veins has a Re‐Os isochron age of 831 ± 11 Ma, indicating that the Dahongshan Fe‐Cu deposit experienced hydrothermal superimposed mineralization in Neoproterozoic. The molybdenite has a Re concentration of 99.7–382.4 ppm, indicating that the Re of the hydrothermal vein ores were primarily derived from the mantle. The δ34S values of sulfides from the hydrothermal ores are 2‰–8‰ showing multi‐peak tower distribution, suggesting that S in the ore‐forming period was primarily derived from magma and partially from calcareous sedimentary rock. Furthermore, the abundance of radioactive Pb increased significantly from ore‐bearing strata to layered and hydrothermal vein ores, which may be related to the later hydrothermal transformation. The composition of H and O isotopes within the hydrothermal quartz indicates that the ore‐forming fluid is a mixture of magmatic water and a small quantity of water. These results further indicate that the late hydrothermal orebodies were formed by the Neoproterozoic magmatic hydrothermal event, which might be related to the breakup of the Rodinia supercontinent. Mantle derived magmatic hydrothermal fluid extracted ore‐forming materials from the metavolcanic rocks of Dahongshan Group and formed the hydrothermal (‐vein) type Fe‐Cu orebodies by filling and metasomatism. [ABSTRACT FROM AUTHOR]

The Talnikovoye ore field, where previous academic research and exploration works revealed porphyry copper mineralization, is described. Our data show that the mineralization is confined to the Turonian granodiorite and quartz diorite intrusions (91 Ma, U–Pb metohod) and accompanying hydrothermal–explosive breccias. Biotite–epidote–chlorite propylites are widespread within the ore field; in the southern part, quartz–sericite phyllic alteration is superimposed on the K-feldspar alteration halo. The ore occurs in zones of intense quartz, chlorite–epidote–quartz (with chalcopyrite and molybdenite), sulfide-potassium feldspar–quartz (with chalcopyrite and bornite), and sulfide–quartz–sericite (with chalcopyrite) stockwork veining with copper–molybdenum mineralization. They have moderate concentrations of Cu (0.1–0.3%, reaching 1.1%) and Mo (up to 0.1%), low concentrations of Au (up to 0.1 g/t) and Ag (up to 2.6 g/t), and have a Cu–Mo–(Au, Ag, Pb, Zn, Sb, and As) geochemical signature. Fluid inclusion data suggest the formation of quartz in mineralized veinlet during the magmatic–hydrothermal transition (430–150°С) with solutions at high (50 wt % NaCl equiv.), medium and low concentrations (5–18.9 wt % NaCl equiv.) involved under the cooling–dilution scenario. The values of the main geochemical indicators, such as Cu/Mo (30–60) and Cu/Au (>1 × 105) ratios allowed us to assign the Talnikovoye ore field to the porphyry copper–molybdenum type characteristic of continental-margin volcano-plutonic belts formed on the mafic island-arc basement. The geochemical parameters of ore-bearing porphyry granitoids indicate their formation in a setting of a subduction-to-transform plate boundary transition. [ABSTRACT FROM AUTHOR]

In this study, GX2 was applied as a new high-efficiency chalcopyrite depressant to selectively separate molybdenite from Cu-Mo sulfide ores. The flotation performance and its interaction mechanisms with chalcopyrite and molybdenite were investigated using single-mineral and artificial-mixed-ore flotation, contact angle measurements, zeta-potential measurements, infrared spectroscopy, and X-ray optoelectronic spectrum analysis. The results indicated that molybdenite could be selectively separated from chalcopyrite under the optimal flotation conditions of pH 9.0, 80 mg/L GX2, 20 mg/L kerosene, 10 mg/L MIBC, and a flotation time of 3 min, while the molybdenite and chalcopyrite recoveries were around 90% and 5%, respectively. It was confirmed that GX2 could save ten times the depressant dosage compared to that of the Na2S baseline to achieve a similar separation efficiency. The contact angle test, zeta potential, infrared spectrum, and XPS results show that GX2 may be adsorbed on the surface of chalcopyrite via chemical adsorption, and the hydrophilic substances formed change its hydrophobicity, whereas the effect on the floatability of molybdenite is small, resulting in the excellent separation efficiency of chalcopyrite and molybdenite via flotation. [ABSTRACT FROM AUTHOR]

Depressants are critical reagents for the selective separation of minerals in froth flotation. They serve a vital role in preferentially making the gangue minerals hydrophilic and prevent them from reporting to the mineral-rich froth phase. Current practice involves the use of inorganic depressants, which are toxic and non-biodegradable. Environmentally friendly, flexible and affordable flotation depressants are needed due to the depletion of easy-to-process high-grade ores as well as sustainability and environmental concerns. This paper discusses various organic depressants that have been adopted for selective depression of unwanted minerals in chalcopyrite flotation. The origin and chemistry, organic depressant-gangue minerals interaction mechanism, and the use of organic depressants in the most common chalcopyrite-flotation instances, including chalcopyrite separation from galena, molybdenite, sphalerite, pyrite, pyrrhotite, talc, serpentine and carbonaceous materials, are discussed. This review shows that organic depressants can partially or fully replace current inorganic depressants used in suppressing both sulfide and non-sulfide gangue minerals in chalcopyrite flotation. In this review, a well-detailed and well-referenced discussion is provided for the current state of organic depressants in chalcopyrite flotation, as well as a valuable discussion is provided to comparatively evaluate the depression performance of the various reported organic depressants. Finally, suggestions are made regarding future research challenges and directions. The recent advancements, developing features, and research prospects discussed in this article will provide a helpful reference for academics who want to delve deeper into the greening of chalcopyrite flotation process. [ABSTRACT FROM AUTHOR]

This work aims to understand the distribution and migration mechanisms of U and Mo between surface sediment and water in acid mine drainage (AMD) regions near a molybdenum mining region. A series of river sediment and water samples near the Jinduicheng mining area, one of the largest deposits of molybdenite ore in Asia, were collected and analyzed. Our results indicate that: (1) The pH value of river water samples increases with distance from upstream to downstream, while the pH has poor correlation with Mo and U; (2) The content of Mo and U in the sediment are significantly higher than the background value, which suggests potential pollution; (3) The content of Mo and U in the water and sediments in the lower reaches of the Wenyu river is significantly linearly related with the distance from the mining area, suggesting that AMD is a potential source; (4) BCR analysis shows that Mo in river sediments mainly existed as the residual, while U mainly existed as the non-residual; (5) The distribution coefficient Kd(Mo) exceeds Kd(U), indicating that Mo is enriched in sediments while U is more prone to porewater. [ABSTRACT FROM AUTHOR]

In this study, hydroxypropyltrimethyl ammonium chloride chitosan (HACC) was first introduced as a depressant during separating chalcopyrite from molybdenite (Cu-Mo). The selective effects of HACC on the separation of Cu-Mo were conducted by single-mineral flotation experiments. The findings from this study revealed that HACC helped separate Cu and Mo efficiently at pH 6 with 8 mg/dm3 of HACC, resulting in 76.22% and 5.38% of Mo and Cu flotation recovery, respectively. The adsorption mechanism of HACC was investigated via zeta potential, adsorption density, and contact angle measurement along with FT-IR and XPS analyses. The contact angle and adsorption density measurements offer indisputable proof that HACC can adsorb on the surface of chalcopyrite. Furthermore, FT-IR and XPS analyses confirm that N atoms in quaternary ammonium groups of HACC interact with Cu sites on the surface of chalcopyrite. The findings also suggest that HACC adsorbs on the surface without significantly impacting molybdenite. All these results confirm that HACC can be an effective chalcopyrite depressant. [ABSTRACT FROM AUTHOR]

Lithium‐ion capacitor (LIC) is a promising energy storage device, which combines double advantages of high‐energy lithium‐ion batteries (LIBs) and high‐power supercapacitors. However, the reported anode materials for LICs are synthesized based on the high‐purity chemicals under complicated and time‐consuming conditions, which exhibit a prohibitive cost in practical application. Herein, natural molybdenite is employed as the precursor to construct a high‐capacity and low‐cost anode material of LICs. Specifically, molybdenite is exfoliated into thin‐layer MoS2 under the interaction of hydrazine hydrate and sodium hydroxide, and then coupled with reduced graphene oxide to form a MoS2@rGO composite. Resulting from high reactive activity and structural stability, the MoS2@rGO anode shows excellent lithium‐ion storage performance including high specific capacity (936 mAh g−1 at 100 mA g−1) and rate capability (446 mAh g−1 at 5000 mA g−1). By using MoS2@rGO as an anode and activated carbon as a cathode, the assembled LIC device provides a maximum energy density of 105 Wh kg−1. Even at a high power density of 25 000 W kg−1, the energy density is still up to 65 Wh kg−1. This work provides a reference for the commercial utilization of natural molybdenum resources in the energy storage field. [ABSTRACT FROM AUTHOR]

The Hongyuan porphyry Mo–Cu deposit (PMCD) is a rare example of a "reduced" deposit, in contrast to classical oxidized porphyry Cu or Mo–Cu deposits. It is characterized by an ilmenite–series I–type felsic granitoid intrusion, reduced ore‐forming fluids with methane‐rich fluid inclusions, and widely distributed primary pyrrhotite. Mo–Cu mineralization in the Hongyuan PMCD occurs as disseminated in porphyry, granular in miarolitic cavity, and vein‐type in the quartz vein. These three types of mineralization are generally produced in the late magmatic period, magmatic‐hydrothermal transition period, and hydrothermal period, respectively. Molybdenite from miarolitic cavities shows a greater contribution from mantle fluid, as evidenced by mantle He proportions of 37.6%–16.8%. Molybdenite in quartz veins has relatively lower mantle He proportions of 1.63%–10.5%, indicating a predominantly crustal fluid source. The 3He/4He variations of these two groups of molybdenite illustrate an increasing input of crustal fluid during the magmatic to hydrothermal transition. Molybdenite samples from miarolitic cavities and quartz veins yield a Re‐Os model age of 300.5 ± 3.7 Ma, which is consistent with the U–Pb ages of zircons in the wallrock porphyries (300–302 Ma). This further indicates simultaneous diagenesis accompanied by mineralization. The Sr–Nd isotopic compositions (initial 87Sr/86Sr: 0.703404–0.703552; initial 143Nd/144Nd: 0.512585–0.512655; εNd[t]: +6.56 to +7.90) and young T2DM model ages (421–531 Ma) of the Hongyuan porphyries suggest that these rocks were derived from partial melting of the basaltic lower crust. We propose that mantle‐derived fluids rose up and mixed with fluids from the lower crust under an extensional tectonic setting, forming mantle‐like Sr–Nd–He–Ar isotopic compositions. The pre‐mineralization stage of the Hongyuan reduced PMCD is marked by quartz‐molybdenite ± K‐feldspar ± pyrite veins or veinlets and miarolitic cavities in the intensively potassic alteration zone. These veins formed at high temperatures (400–476°C) and high salinities (47.5–56.6 wt.%). The syn‐mineralization stage is the main metallogenic stage represented by numerous quartz‐molybdenite ± pyrrhotite veins associated with moderate to high temperatures (248°C–424°C) and low to high salinities (1.57–50.1 wt.%). The post‐mineralization stage is characterized by low temperatures (104–270°C) and low salinities (0.35–8.81 wt.%). Fluid immiscibility, mixing with meteoric water, ore fluid‐wall rock interactions, and decreasing temperature and salinity have played important roles during molybdenum mineralization. [ABSTRACT FROM AUTHOR]

The Hannivka molybdenum deposit is located in the northeastern side of the Kryvyi Rih structure, within the East Hannivka monocline. Molybdenum mineralization is confined to the contact zone of granitoids of the Demuryne complex with metabasites of the Novokryvorizka suite. The main volume of molybdenum mineralization is concentrated in the exocontact, in metabasites, and only 10-15% in endocontact granitoids. The molybdenum-bearing zone is represented by schistose, moderately quartzized and biotitized fine-grained metabasalts, which contain quartz, epidote-quartz, epidote, sometimes feldspar-quartz veins and veinlets and moderate (0.5-3%) sulfide mineralization. The volume of vein material ranges from 0.5 to 3-5%. The geological-morphological type of mineralization is defined as linear stockwork. Leading processes responsible for the development of molybdenite are quartzization and biotitization, namely silicic-alkaline metasomatism. Using JSM-6700F і JXСА-733 electron microscopes, the following ore minerals have been diagnosed and studied: magnetite, ilmenite, molybdenite, loellingite, arsenopyrite, pyrrhotite, pyrite, chalcopyrite, sphalerite. Based on their structural positions and relationships, several successive ore stages have been identified: early oxide (ilmenite-magnetite), main sulfide with molybdenite, potentially gold-bearing arsenide-sulfoarsenide-sulfide and late sulfide. Molybdenite is localized in zalbands of thin (1-3 mm, occasionally up to 2 cm) quartz veinlets, sometimes in the form of boudinaged structures, lenses and pockets reaching sizes up to 4 cm, as well as in host metabasalts and plagiogranites. Conditionally, three morphological types of molybdenite can be distinguished: a) medium-sized elongated tabular, platy, and foliated crystals ranging in size from 0.1 mm to 1.5-2 mm, which are oriented subparallel to the vein structures and rock foliation; b) fine-grained (from 10-20 µm to 0.1 mm) elongated flakes uniformly or randomly oriented; c) isometric crystals of hexagonaltabular habitus with sizes ranging from 0.1 to 0.7 mm. Outlined are several areas that require further investigation: epitaxial growths of molybdenite and silicates and the conditions of their formation, the time of formation of molybdenite and ore-generating granitoids. [ABSTRACT FROM AUTHOR]

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The Lower Urgen molybdenum deposit (44,856 t Mo @ 0.141%), situated in the northern Great Xing'an Range, is a newly discovered porphyry molybdenum deposit. Mineralization is characterized by veinlet-disseminated- and vein-type quartz–sulfide orebodies primarily occurring in the cupola of the Early Cretaceous granite porphyry stock. In this study, we present a detailed description of the ore geology, molybdenite Re-Os dating, H-O-S-Pb isotopic compositions, and fluid inclusion (FI) analyses including petrography, laser Raman, and microthermometry to precisely constrain the timing of ore formation, the origin of ore-forming fluids and materials, as well as the metal precipitation mechanism. Molybdenite Re-Os dating yielded two model ages of 141.2 ± 1.5 and 147.7 ± 1.7 Ma, coeval with the regional Late Jurassic–Early Cretaceous molybdenum metallogenesis. The hydrothermal process can be divided into three stages: the quartz–molybdenite(–pyrite) stage, quartz–polymetallic sulfide stage, and quartz–carbonate stage. Four types of FIs were distinguished for quartz, including two-phase liquid-rich (L-type), saline (S-type), CO2-rich (C1-type), and CO2-bearing (C2-type) FIs. Microthermometric data showed that the homogenization temperatures and salinities from the early to late stages were 240–430 °C, 5.0–11.9, and 30.1–50.8 wt% NaCl equiv.; 180–280 °C and 3.0–9.1 wt% NaCl equiv.; and 120–220 °C and 0.2–7.9 wt% NaCl equiv., respectively, suggesting a decreasing trend. H-O isotopic compositions indicate that the ore-forming fluids were initially of magmatic origin with the increasing incorporation of meteoric water. S-Pb isotopic compositions indicate that the ore-forming materials originated from granitic magmas, and the mineralization is genetically related to the ore-bearing granite porphyry stock in the deposit. Fluid immiscibility and fluid–rock interaction are collectively responsible for the massive deposition of molybdenite in stage 1, whereas fluid mixing and immiscibility played a critical role in the deposition of polymetallic sulfide in stage 2. [ABSTRACT FROM AUTHOR]

Copyright of Multipurpose Utilization of Mineral Resources / Kuangchan Zonghe Liyong is the property of Multipurpose Utilization of Mineral Resources Editorial Office 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.)

Copyright of Journal of Northeastern University (Natural Science) is the property of Dongbei Daxue Xuebao 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 optical and electrical properties of monolayer MoS2 and MoS2 adsorbed with chlorine under uniaxial strain is investigated by using DFT-D2 Grimme approach. As a result of mechanical strain, bandgap of semiconducting monolayer MoS2 and chlorine adsorbed MoS2 decreases (in a zig-zag manner), which leads to transition from direct to indirect bandgap material and a semiconductor to metal transition. The red shift mechanism, in which the absorption peak relocated to the lower energy regions of electromagnetic spectrum, was seen in MoS2 structures subjected to strains of 0.6%, 0.8%, and 1% and also in Cl adsorbed MoS2 structures subjected to strains of 0.1%, 0.2%, 0.4%, 0.6%, 0.8%, and 1%. Blue shift phenomenon is observed in the remaining strained structures of MoS2 where the applied values of strain are 0.1%, 0.2% and 0.4%, causing the absorption peaks to shift towards the higher energy values. By application of uniaxial strain on all the structures, absorption boost as well as spread over the entire visible spectrum (380–780 nm) and a very limited absorption is observed in UV band (below 350 nm). There is a good correlation between dielectric constant and refractive index of all adsorbed nanostructures. Additionally, all strained structures are highly efficient across the visible spectrum, making them ideal for optoelectronics and solar harvesting. [ABSTRACT FROM AUTHOR]

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Life on Earth depends on N2‐fixing microbes to make ammonia from atmospheric N2 gas by the nitrogenase enzyme. Most nitrogenases use Mo as a cofactor; however, V and Fe are also possible. N2 fixation was once believed to have evolved during the Archean‐Proterozoic times using Fe as a cofactor. However, δ15N values of paleo‐ocean sediments suggest Mo and V cofactors despite their low concentrations in the paleo‐oceans. This apparent paradox is based on an untested assumption that only soluble metals are bioavailable. In this study, laboratory experiments were performed to test the bioavailability of mineral‐associated trace metals to a model N2‐fixing bacterium Azotobacter vinelandii. N2 fixation was observed when Mo in molybdenite, V in cavansite, and Fe in ferrihydrite were used as the sole sources of cofactors, but the rate of N2 fixation was greatly reduced. A physical separation between minerals and cells further reduced the rate of N2 fixation. Biochemical assays detected five siderophores, including aminochelin, azotochelin, azotobactin, protochelin, and vibrioferrin, as possible chelators to extract metals from minerals. The results of this study demonstrate that mineral‐associated trace metals are bioavailable as cofactors of nitrogenases to support N2 fixation in those environments that lack soluble trace metals and may offer a partial answer to the paradox. [ABSTRACT FROM AUTHOR]

Rhenium, a unique and valuable metal with exceptional properties which is vital in various industrial applications, primarily found in conjunction with minerals like molybdenite and chalcopyrite, predominantly in western countries. Despite its rarity, understanding its geological distribution, geochemical characteristics, atomic structure, and behavior is essential. This paper provides a concise overview of the geological and geographical occurrences of rhenium, shedding light on its formation within both igneous and sedimentary environments. Additionally, it examines its economic significance, emphasizing its critical role in industries like aerospace, electronics, and petrochemicals due to its high-temperature resistance, corrosion resistance, and electrical conductivity enhancement. This comprehensive exploration highlights the importance of rhenium as a byproduct of mining, contributing significantly to technological advancements and innovation across various sectors. [ABSTRACT FROM AUTHOR]

In recent years, transition metal dichalcogenides have received great attention since they can be prepared as two‐dimensional semiconductors, presenting heterodesmic structures incorporating strong in‐plane covalent bonds and weak out‐of‐plane interactions, with an easy cleavage/exfoliation in single or multiple layers. In this context, molybdenite, the mineralogical name of molybdenum disulfide, MoS2, has drawn much attention because of its very promising physical properties for optoelectronic applications, in particular a band gap that can be tailored with the material's thickness, optical absorption in the visible region and strong light–matter interactions due to the planar exciton confinement effect. Despite this wide interest and the numerous experimental and theoretical articles in the literature, these report on just one or two specific features of bulk and layered MoS2 and sometimes provide conflicting results. For these reasons, presented here is a thorough theoretical analysis of the different aspects of bulk, monolayer and bilayer MoS2 within the density functional theory (DFT) framework and with the DFT‐D3 correction to account for long‐range interactions. The crystal chemistry, stiffness, and electronic, dielectric/optical and phonon properties of single‐layered, bilayered and bulk molybdenite have been investigated, to obtain a consistent and detailed set of data and to assess the variations and cross correlation from the bulk to single‐ and double‐layer units. The simulations show the indirect–direct transition of the band gap (K–K′ in the first Brillouin zone) from the bulk to the single‐layer structure, which however reverts to an indirect transition when a bilayer is considered. In general, the optical properties are in good agreement with previous experimental measurements using spectroscopic ellipsometry and reflectivity, and with preliminary theoretical simulations. [ABSTRACT FROM AUTHOR]

A simple, rapid, cost‐effective and non‐enzymatic amperometric sensor for sensitive and simultaneous determination of uric acid (UA), dopamine (DA), and ascorbic acid (AA) was developed based on a new combination of carbon black (CB) and molybdenite (MLN) modified glassy carbon electrode (GCE). The synergistic effect of CB and MLN can increase electrode's conductivity, accelerate the electrochemical catalytic reaction and enhance the oxidation currents of UA, DA and AA. Cyclic voltammetry demonstrated the sensor to perform excellently in the electrochemical oxidation of AA, DA and UA, respectively. The oxidation potentials are well separated (oxidation peaks at −50 mV, 200 mV and 350 mV vs. Ag/AgCl) for AA, DA and UA with the detection limits of 5 μmol/L, 8.7 μmol/L and 9 μmol/L (S/N=3), respectively. The MLN‐CB/GCE sensor also demonstrated superior electrochemical properties including good stability, selectivity and reproducibility. In addition, the prepared sensor for UA allowed the determination of UA in highly diluted body fluids (urine), and the analytical results obtained by the present sensor were in good agreement with those obtained by conventional spectrophotometry. [ABSTRACT FROM AUTHOR]

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This short communication presents residence time distribution (RTD) measurements and modeling in a 16 m3 Siemens flotation cell, as the first RTD characterization in an industrial-scale pneumatic cell. The Siemens cell was installed as a pre-rougher machine in a Cu-Mo selective plant. This plant recovered molybdenite as an enriched product, depressing copper-bearing minerals. Irradiated non-floatable solid and Br82 in water solution were employed as solid and liquid tracers, respectively. The tracers were instantly injected into the Siemens cell, and the inlet and outlet concentrations were directly measured by external non-invasive detectors. From the flotation literature, three model structures for the RTDs were evaluated, including perfect mixing, one large perfect mixer and one small perfect mixer in series (LSTS), and N perfectly mixed reactors in series. A transport delay was incorporated for all models. The LSTS representation was more consistent with the experimental data, showing that the Siemens cell RTDs presented significant deviations with respect to perfect mixing and plug-flow regimes. From the industrial measurements, mean residence times of 4.1–5.2 min were estimated. [ABSTRACT FROM AUTHOR]

Copyright of Uzbek Chemical Journal / O'Zbekiston Kimyo Jurnali is the property of Institute of General & Inorganic Chemistry of Academy of Sciences of Republic of Uzbekistan 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.)

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The Banjing tungsten deposit, which has been discovered recently, is located in the northernmost part of the Dabu pluton, southern Jiangxi Province, China. In this study, zircon LA‐ICP‐MS U–Pb dating of the fine‐grained porphyritic biotite granite indicate that it was formed in the early Yanshanian (159.4 ± 2.5 Ma–161.6 ± 0.8 Ma). Whole‐rock geochemical studies have shown the fine‐grained porphyritic biotite granite has SiO2 of 75.82%–76.84%, Al2O3 12.50%–12.87%, MgO 0.07%–0.20%, and CaO 0.64%–1.09%, with A/CNK of 1.017–1.038. It has a total rare earth elements content of 93.9–118.9 ppm with strong negative Eu anomalies (δEu = 0.021–0.081). The biotite granite is enriched in Rb, Th, U, Nd and depleted in Ba, Sr, Nb, Ti. These data suggest the Dabu pluton belongs to S‐type granite. This pluton has ISr of 0.71212–0.72929 and εNd(t) from −9.60 to −10.62 with Nd model ages concentrated in 1732–1838 Ma. These isotopic data in combination with zircon Hf isotopes suggest the biotite granite originated from partial melting of the Middle Proterozoic metamorphic supracrustal rocks in South China, with a minor contribution from juvenile crust. Meanwhile, this study has obtained Re–Os isochron ages of the intrusion‐related and quartz vein‐type molybdenum mineralization are 156.3 ± 2.7 Ma and 157.0 ± 1.1 Ma in the Banjing tungsten deposit, respectively. Sericite from the greisen‐type tungsten‐molybdenum ore has an 40Ar–39Ar plateau age of 156.4 ± 1.0 Ma, interpreted as the formation age of this deposit. Collectively, the Banjing tungsten deposit is considered as a product of the early Yanshanian large‐scale peak mineralization in South China, which was formed in an extensional intracontinental environment caused by the subduction of the Palaeo‐Pacific Plate. [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.)

Modern trends in technological improvement for producing high-quality rhenium-containing molybdenum concentrates are aimed at developing environmentally friendly solutions com-pared to traditional ones, involving a reduction in consumption or complete replacement of toxic substances and the use of plant reagents and microorganisms and make it possible to eliminate energy-intensive processes of steaming and roasting. It is known that up to 25%–30% of Mo, Cu and Re goes to rough flotation tailings and is lost in wastes. Those losses are a consequence of the ore composition variability, chalcopyrite–molybdenite ratio, an increase in the proportion between primary copper sulfide and finely disseminated molybdenite and the recovery of floating pyrite. High rates of valuable metal recovery into bulk concentrate can be achieved by using new compositions of flotation reagents that selectively change the hydrophobic properties of the target minerals. The application of new reagent compositions, including novel chemicals—dithiopyrylmethane (DTM), composite reagent (CR) and conventional butyl xanthate (ButX)—was theoretically and experimentally substantiated for the effective rhenium extraction in the processing of hard-to-beneficiate complex molybdenum ores. It is identified that DTM forms a complex DTM–Re compound and chemically adsorbed on rhenium-containing molybdenite providing an increase in Re recovery into the bulk Cu–Mo–Re concentrate by 17%, reducing by two times the loss of rhenium with flotation tailings, and the subsequent 97.6% Re extraction of the molybdenum concentrate by autoclave leaching. [ABSTRACT FROM AUTHOR]

The effect of ethyl thioglycolate organic small molecule inhibitors on chalcopyrite molybdenite flotation behaviour is investigated via single mineral micro-flotation tests, zeta potential tests, and X-ray photoelectron spectroscopy (XPS) analysis. Results of the flotation test indicate that ethyl thioglycolate organic small-molecule inhibitors can effectively separate Cu and Mo and selectively inhibit chalcopyrite under weak alkaline conditions. Infrared spectroscopy and XPS analysis show that hydrophilic functional groups C=O and -COOH in the ethyl thioglycolate organic small molecules can chemically adsorb onto the chalcopyrite surface. Moreover, ethyl thioglycolate has no obvious effect on zeta potential of molybdenite. Therefore, ethyl thioglycolate can effectively separate chalcopyrite and molybdenite. [ABSTRACT FROM AUTHOR]

Flotation kinetic models can be applied to describe the flotation process and to predict mineral recoveries. However, the size composition of the target minerals in the feed ore fluctuates considerably, resulting in insufficient accuracy with flotation kinetic models. There have been many studies that focus on the investigation of flotation kinetics with different particle sizes, while the optimization methods for flotation kinetic models based on particle size effects have not been reported. In this paper, flotation tests, optical microscope observations, and particle size analysis were used to identify the reasons for the decrease in accuracy of the flotation kinetic model due to changes in the composition of molybdenite particle size. Additionally, an optimization method for the flotation kinetic model was developed based on the particle size effect. The test results show that the accuracy of the flotation kinetic model for fixed particle size minerals is very high, but the predicted results for flotation recoveries of different particle size mineral mixtures have large deviations. The poor accuracy might be due to the autogenous carrier effect caused by the particle size composition fluctuating considerably. The optimization method for the flotation kinetic model is based on the particle size effect. The model can accurately describe the flotation process of molybdenite with different size compositions of molybdenite and predict the flotation recovery of molybdenite. [ABSTRACT FROM AUTHOR]

Copyright of Gold (1001-1277) is the property of Gold Magazine Editorial Office 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.)

Compositional features of a total of 1887 gold alluvial particles from six localities to the south of Loch Tay in central Scotland were interpreted to establish different types of source mineralization. Populations of gold particles from each locality were grouped according to alloy and inclusion signatures. Inclusion suites provided the primary discriminant with gold from Group 1 localities showing a narrow range of simple sulphide and sulphoarsenide inclusion species, whereas a wide range of minerals including molybdenite, bornite and various Bi and Te- bearing species were identified in gold from Group 2 localities. Whilst the range of Ag in alloys in all populations was similar, higher incidences of measurable Hg and Cu were detected in Group 1 and Group 2 gold samples respectively. The application of compositional templates of gold from other localities worldwide indicated that Group 1 gold is orogenic and Group 2 gold is a mixture of porphyry and epithermal origin; a result that is sympathetic to the spatial relationships of sample localities with local lithologies. This approach both provides an enhanced level of understanding of regional gold metallogeny where in situ sources remain undiscovered, and permits clearer targeting of deposit types during future exploration. [ABSTRACT FROM AUTHOR]

As a novel technique with a wide range of applications, microbial fuel cell (MFC) could simultaneously remove organic contaminants and heavy metals in complex wastewater, despite striking differences in physicochemical properties of these contaminant. But its wastewater treatment efficiency is restricted by its lower generation performance. However, approaches for the modification of MFCs' cathode with appropriate catalyst could effectively overcome this limitation. Herein, a new-type efficient cathode catalyst was invented through modifying natural molybdenite via one-step oxidation method. In this case, molybdenite had many changes in morphology (wave-shaped bending, fragmentation and decrescent diameter) during oxidation modification process, and oxidation-modified molybdenite could provide much more active sites for the cathode. After applying this novel cathode catalyst, the electric generation capacity of MFC system increased by 5.08 times, and its simultaneous degradation efficiency of methyl blue (MB) and Cr (VI) increased by 3.35 times (compared with graphite cathode MFC). This study provides a novel low-carbon and environmentally friendly way to prepare high efficiency cathode catalyst materials and provides a new idea of simultaneous purification for organic and metallic pollutants from complex wastewater. [ABSTRACT FROM AUTHOR]