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Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,metallurgy and Materials 2025年第2期32卷 335-345页

作者： Feng Zhang Chenyang Zhang Linlin Wu Wei Sun Hongliang Zhang Jianhua Chen Yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group co.ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis

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International Journal of Minerals,metallurgy and Materials 2025年第1期32卷 58-69页

作者： Jie Wang Wei Wang Xuheng Chen Junfang Bao Qiuyue Hao Heng Zheng Runsheng Xu School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China Key Laboratory for Ferrous metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Institue of Ironmaking Technology Baosteel Central Research InstituteShanghai 201999China State Key Laboratory of Advanced metallurgy University of Science and Technology BeijingBeijing 100083China

The utilization of iron coke provides a green pathway for low-carbon *** uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was ***,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric *** findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and *** provides more adsorption sites for co_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron *** the heating rate in non-isothermal gasification can enhance the reactivity of iron *** metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon *** kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore ***,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.

关键词： low-carbon ironmaking iron coke gasification structural evolution kinetic model

Preparation of co/S co-doped carbon catalysts for excellent methylene blue degradation

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International Journal of Minerals,metallurgy and Materials 2025年第1期32卷 169-181页

作者： Haixu Li Haobo He Tiannan Jiang Yunfei Du Zhichen Wu Liang Xu Xinjie Wang Xiaoguang Liu Wanhua Yu Wendong Xue School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China beijing Jinyu Tongda Refractory Technologies co. Ltd.Beijing 100085China

S and co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)*** effects of two different mixing routes were identified on the MB degradation ***,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with ***,the degradation parameters,including pH and MOF-AEP dosage,were ***,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.

关键词： advanced oxidation process alcohol solvent evaporation hydrogen bond S and co co-doped carbon catalysts wastewater remediation

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(beijing)Materials Sci.&Tech.co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

Tribological characteristics of C/C-SiC braking composites under dry and wet conditions

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中国有色金属学会会刊：英文版 2008年第5期18卷 1071-1075页

作者：李专肖鹏熊翔朱苏华 State Key Laboratory of powder metallurgy Central South University Hunan Boyun New Material co.ltd

C/C-SiC braking composites,based on reinforcement of carbon fibers and matrices of carbon and silicon carbide,were fabricated by warm compaction and in situ reaction *** tribological characteristics of C/C-SiC braking composites under dry and wet conditions were investigated by means of MM-1000 type of friction testing *** influence of dry and wet conditions on the tribological characteristics of the C/C-SiC composites was *** dry condition,C/C-SiC braking composites show superior tribological characteristics,including high coefficient of friction (0.38),good abrasive resistance (thickness loss is 1.10 μm per cycle) and steady *** main wear mechanism is plastic deformation and abrasion caused by *** wet condition,frictional films form on the worn *** coefficient of friction (0.35) could maintain mostly,and the thickness loss (0.70 μm per cycle) reduces to a certain ***,braking curves are steady and adhesion and oxidation are the main wear mechanisms.

关键词： C/C-SiC 焊接条件摩擦特征制动复合材料

Plasmon-induced local electric field improved hydrogen evolution reaction on Ag/Mo_(2)C nanosheets

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Nano Research 2025年第1期18卷 270-277页

作者： HuangJingWei Li Xin Zi Jun Wu Xinli Wang Li Zhu Qiyou Wang Jianfu Han Junwei Fu Hongmei Li Kai Huang Yu Chen Min Liu School of Physics State Key Laboratory of Powder MetallurgyHunan Joint International Research Center for Carbon Dioxide Resource UtilizationCentral South UniversityChangsha 410083China School of metallurgy and Environment Central South UniversityChangsha 410083China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Nano-Institute Munich Faculty of PhysicsLudwig-Maxilimians-Universität MünchenMünchen 80539Germany Hunan Institute of Advanced Sensing and Information Technology Xiangtan UniversityXiangtan 411105China

Electrocatalytic water splitting offers a promising way for hydrogen production with near-zero ***,such as molybdenum carbides(Mo_(2)C),are promising materials for hydrogen evolution reaction(HER)but still suffer from poor intrinsic water activation ***,we developed a plasmon-induced local electric field(PILEF)strategy to solve this ***(Ag)nanoparticles decorated Mo_(2)C nanosheets(Ag/Mo_(2)C)were successfully prepared by electrostatic *** visible light excited the PILEF on Ag/Mo_(2)C remarkably reducing the activation energy by 92.7 kJ·mol^(-1)from 147.3 kJ·mol^(-1)of Mo_(2)C to 54.6 kJ·mol^(-1).As a result,the plasmonic Ag/Mo_(2)C significantly enhances~2.3-fold of the current density from 2.8 mA·cm^(-2)of Mo_(2)C to 6.5 mA·cm^(-2)at-3 V *** and reduces the overpotential by 104 mV from 403 mV of dark state to 299 mV of light state at the current density of 10 mA·cm^(-2),achieving better performance than reported *** research demonstrates that PILEF enhances HER activities,offering a potential strategy for boosting the intrinsic activities of catalysts.

关键词： sliver particles plasmon effect field effect hydrogen evolution reaction(HER) electrocatalysis

Synthesis of nanostructured Mg_2FeH_6 hydride and hydrogen sorption properties of complex

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Transactions of Nonferrous Metals Society of China 2010年第12期20卷 2281-2288页

作者：李松林汤盛龙刘燚彭书科崔建民 State Key Laboratory of powder metallurgy Central South University powder metallurgy corporation ltd. Laiwu Iron and Steel Group

Reactive mechanical alloying(RMA)was carried out in a planetary ball mill for the synthesis of ternary hydride Mg2FeH6 for hydrogen *** formation mechanism of Mg2FeH6 in RMA process and the sorption properties of the products were *** results show that Mg2FeH6 has a yield ratio around 80%,and a grain size below 10 nm in the powder synthesized by milling 3Mg+Fe mixture for 150 h under the hydrogen pressure of 1 *** synthesized powder possesses a high hydrogen capacity and good sorption kinetics,and absorbs 4.42%(mass fraction)of hydrogen within 200 s at 623 K under the hydrogen pressure of 4.0 *** releasing hydrogen at 653 K under 0.1 MPa,it desorbs 4.43%(mass fraction)of hydrogen within 2 000 *** addition of Ti increases the hydrogen desorption rate of the complex in the initial 120 s of the desorption process.

关键词： reactive mechanical alloying(RMA) metal hydride hydrogen storage material kinetics fuel cell

Fabrication of solid-phase-sintered Si C-based composites with short carbon fibers

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International Journal of Minerals,metallurgy and Materials 2014年第11期21卷 1141-1145页

作者： Xian-hui Li Qing-zhi Yan Yong-jun Han Mei-qi Cao Chang-chun Ge Institute of Special Ceramics and powder metallurgy University of Science and Technology Beijing

Solid-phase-sintered Si C-based composites with short carbon fibers（Csf/SSi C） in concentrations ranging from 0 to 10wt% were prepared by pressureless sintering at 2100°C. The phase composition, microstructure, density, and flexural strength of the composites with different Csf contents were investigated. SEM micrographs showed that the Csf distributed in the SSi C matrix homogeneously with some gaps at the fiber/matrix interfaces. The densities of the composites decreased with increasing Csf content. However, the bending strength first increased and then decreased with increasing Csf content, reaching a maximum value of 390 MPa at a Csf content of 5wt%, which was 60 MPa higher than that of SSi C because of the pull-out strengthening mechanism. Notably, Csf was graphitized and damaged during the sintering process because of the high temperature and reaction with boron derived from the sintering additive B4C; this graphitization degraded the fiber strengthening effect.

关键词： fiber-reinforced composites silicon carbide carbon fibers solid phase sintering microstructure

Synthesis of Nano-Crystalline Diamond Film in Hot Filament Chemical Vapour Deposition by Adding Ar

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Chinese Physics Letters 2001年第2期18卷 286-288页

作者： ZHANG Yu-Feng ZHANG Fan GAO Qiao-Jun YU Da-Peng PENG Xiao-Fu LIN Zeng-Dong Department of Physics Peking UniversityBeijing 100871 beijing Institute of powder metallurgy Beijing 100078

Nano-crystalline diamond films are successfully deposited on silicon substrates via the hot filament chemical vapour deposition process using a CH_(4)/H_(2)/Ar gas *** as-grown films are analysed by using field emission scanning electron microscopy,micro-Raman spectroscopy and x-ray *** results show that the films consist of nano-diamond grains with sizes ranging from 10 to 100 nm,and argon is an important element in the formation of nano-crystalline diamonds.

关键词： crystalline films vapour