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Efficient recovery of tungsten from scheelite concentrates using a sulfur-phosphorus mixed acid leaching system

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Tungsten 2024年第4期6卷 821-832页

作者： Jiang-Tao Li Li-Li Gao Zhong-Wei Zhao xu-heng liu Xing-Yu Chen School of Metallurgy and Environment Central South UniversityChangsha410083China Key Laboratory of Hunan Province for Metallurgy and Material Processing of Rare Metals Changsha410083China

In recent years,a new process for leaching scheelite concentrates with sulfur-phosphorus mixed acid has been successfully *** process suffers from the elimination of the retarding effect of calcium sulfate,the selective extraction of tungsten from the H_(3)PW_(12)O_(40)-H_(2)SO_(4)-H_(3)PO_(4)mixture solution,and the removal of introduced ***,in this paper,we investigated the inhibition measures of a calcium sulfate-blocking membrane,the selective extraction of tungsten by ion exchange,and the removal of phosphorus by the magnesium ammonium salt *** results showed that the addition of calcium sulfate whisker seeds and a higher H_(3)PO_(4)concentration inhibited spontaneous diffuse nucleation,promoted crystal growth,and avoided the formation of a dense blocking *** 98 wt.%of the scheelite concentrate was digested by H_(2)SO_(4)-H_(3)PO_(4).The selective adsorption of PW_(12)O_(40)^(3-)was realized using D301 resin,and the extraction efficiency of tungsten exceeded 99.9%.After desorption with ammonia water,PW_(12)O_(40)^(3-)was depolymerized into WO_(4)^(2-)and PO_(4)^(3-).99.9 wt.%of phosphorus was removed in the form of MgNH_(4)PO_(4)by the magnesium ammonium salt method,and the residual phosphorus concentration in the solution was lower than 10 mg·L^(-1).After purification,the highest-grade ammonium paratungstate product was prepared by evaporative crystallization.

关键词： Scheelite concentrates Sulfur-phosphorus mixed acid Calcium sulfate Ion exchange Tungsten

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

Comparative kinetic analysis of conventional and ultrasound-assisted leaching of scheelite by sodium carbonate

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Transactions of Nonferrous Metals Society of China 2018年第4期28卷 775-782页

作者： Jin-hong YANG Li-hua HE xu-heng liu Wen-tao DING Yun-feng SONG Zhong-wei ZHAO School of Metallurgy and Environment Central South UniversityChangsha 410083China

For further comprehending the mechanism of the intensification of ultrasound for extraction,the difference of leaching kinetics between the ultrasound-assisted and conventional sodium carbonate leaching of scheelite was studied,and the corresponding kinetic equations were *** results indicate that the obtained apparent activation energy with or without ultrasound is same 72 kJ/mol,and both reactions are controlled by surface chemical *** comparing the leaching kinetics of scheelite by Na2CO3,NaOH and Na3PO4 reactants with or without ultrasound,a general conclusion for scheelite hydrometallurgy is *** the process with the formation of compact product layer,the intensification of the tungsten extraction with ultrasound mainly reflects in the stripping and elimination of product layer,corresponding to the transformation of kinetic controlling step from diffusion controlling step and reduction of apparent activation *** the one without compact product layer or with a loose and porous product layer,the intensification mainly embodies in the increase of frequency factor,and the controlling step and apparent activation energy of the reaction always remain constant.

关键词： scheelite kinetics ultrasound ultrasonic chemistry activation energy

Effect of Mg doping on electrochemical performance of Li_3V_2(PO_4)_3/C cathode material for lithium ion batteries

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Transactions of Nonferrous Metals Society of China 2015年第7期25卷 2266-2271页

作者：罗韵泽何利华刘旭恒中南大学冶金与环境学院长沙410083

Li3Mg（2x）V（2-2x）（PO4）3/C（x=0,0.05,0.1,0.2） composites were synthesized by carbothermic reduction,using a self-made MgNH4PO4/MgHPO4 compound as Mg-doping agent.X-ray diffraction（XRD）,scanning electron microscope（SEM）,electrochemical performance tests were employed to investigate the effect of Mg doping on Li3V2（PO4）3/C *** results showed that a proper quantity of Mg doping was beneficial to the reduction of charge transfer resistance of Li3V2（PO4）3/C compound without changing the lattice structure,which led to larger charge/discharge capacity and better cycle performance especially at high current ***3Mg（2x）V（2-2x）（PO4）3/C sample with x=0.05 exhibited a better performance with initial charge/discharge capacity of146/128 mA·h/g and discharge capacity of 115 mA·h/g at 5C,while these two figures were 142/118 mA·h/g and 90 mA·h/g respectively for samples without Mg doping,indicating that a proper amount of doped Mg can improve the electrochemical performance of LVP *** of these proved that,as a trial Mg dopant,the synthesized MgNH4PO4/MgHPO4 compound exhibited well doping effect.

关键词： lithium vanadium phosphate Mg-doping cathode materials carbothermic reduction

Research and development trends of hydrometallurgy:An overview based on Hydrometallurgy literature from 1975 to 2019

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Transactions of Nonferrous Metals Society of China 2020年第11期30卷 3147-3160页

作者： Li-pan JIA Jiang-jiang HUANG Ze-long MA xu-heng liu Xing-yu CHEN Jiang-tao LI Li-hua HE Zhong-wei ZHAO School of Metallurgy and Environment Central South UniversityChangsha 410083China Hunan Key Laboratory for Metallurgy and Material Processing of Rare Metals Changsha 410083China

Modern hydrometallurgy has been developing for more than 100 years and the related articles keep piling *** on a bibliometric analysis of the articles in Hydrometallurgy,the most authoritative journal in the field of hydrometallurgy,we try to catch the research and development trends from a global ***,keywords burstness shows that rare earth,recycling,lithium,ionic liquid,and thorium are the hotspots in recent years,and the economic and technological reasons behind them were discussed in ***,the proportion of biohydrometallurgy grows fast from 5%to 13%and the related articles are almost all about *** are some new directions such as direct preparation of materials in hydrometallurgical processes and ion-imprinted ***,the advanced instrument analysis methods such as XAFS(X-ray absorption fine structure),gene sequencing,and micro-CT promote the deep understanding of hydrometallurgy ***,the cooperation network and contribution of the main institutes were mapped.

关键词： development trends leaching solvent extraction biohydrometallurgy electro-hydrometallurgy CiteSpace

Measurement of binary phase diagram of Cu_2S-MoS_2 system

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Transactions of Nonferrous Metals Society of China 2013年第1期23卷 271-275页

作者：陈星宇赵中伟郝明明刘旭恒中南大学冶金科学与工程学院长沙410083 中南大学稀有金属冶金与材料制备湖南省重点实验室长沙410083

A novel method,bath smelting process,was developed to treat molybdenite concentrate aiming at the existing problems of traditional *** understand the dissolving behavior of MoS2 in white matte,the binary phase diagram of Cu2S-Mo2S was measured by the cooling curve *** result shows that this system is a simple binary eutectic with a eutectic temperature of（1117.0±3.0）℃ and a eutectic composition of（1.70±0.20）% MoS2 in mass *** the MoS2 addition exceeds 4.48%,MoS2 and Cu2S can form the ternary compound containing CuMo2S3 or *** the temperature range of copper smelting,1200-1300℃,molybdenite can dissolve in the cuprous *** 1200℃,the solubility of molybdenite can reach 14.8%.

关键词： binary system Cu2S-MoS2 bath smelting process solubility eutectic molybdenite

Extraction of lithium from salt lake brine by aluminum-based alloys

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Transactions of Nonferrous Metals Society of China 2015年第10期25卷 3484-3489页

作者：李艳红赵中伟刘旭恒陈星宇钟茂礼中南大学冶金与环境学院长沙410083

Salt lake brine was reacted with activated aluminum-based alloys and lithium was *** effects of aluminum-based alloys on precipitating lithium were investigated and the reasonable alloy used to extract lithium from brine was *** effects of the mole ratio of Al to Li and Ca content of Al-Ca alloy,the initial concentration of lithiumion ion in solution,reaction temperature and reaction time on the adsorption rate of lithium were studied,and the optimized process parameters were *** results show that the mole ratio of Al to Li and Ca content of Al-Ca alloy and reaction temperature have great influences on the precipitation rate of *** precipitation rate of lithium reaches 94.6% under the optimal condition,indicating that Al-Ca alloy is suitable for the extraction of lithium from salt lake brine.

关键词： salt lake brine lithium extraction aluminum matrix composite Al-Ca alloy

Electrochemical behavior of Li^+,Mg^(2+),Na^+ and K^+ in LiFePO_4/FePO_4 structures

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Transactions of Nonferrous Metals Society of China 2013年第4期23卷 1157-1164页

作者：赵中伟司秀芬梁新星刘旭恒何利华中南大学冶金科学与工程学院长沙410083 稀有金属冶金与材料制备湖南省重点实验室长沙410083

Besides Li＋ and Mg2＋, the electrochemical behavior of Na^＋ and K＋ in LiFePO4/FePO4 structures was studied since they naturally coexist with Li＋ and Mg2＋ in brine. The cyclic voltammogram （CV） results indicated that Na＋ exhibits some reversibility in LiFePO4/FePO4 structures. Its reduction peak appears at -0.511 V, more negative than that of Li＋（-0.197 V）, meaning that a relatively positive potential is beneficial for decreasing Na＋ insertion. The reduction peak of K＋ could not be found clearly, indicating that K＋ is difficult to insert into the FePO4 structure. Furthermore, technical experiments using real brine with a super high Mg/Li ratio （493） at a cell voltage of 0.7V showed that the final extracted capacity of Li＋, Mg2＋ and Na＋ that can be attained in 1 g LiFePO4 is 24.1 mg, 7.32 mg and 4.61 mg, respectively. The Mg/Li ratio can be reduced to 0.30 from 493, and the Na/Li ratio to 0.19 from 16.7, which proves that, even in super high Mg/Li ratio brine, if a cell voltage is appropriately controlled, it is possible to separate Li^＋ and other impurities effectively.

关键词： LiFePO4/FePO4 electrodes NaFePO4 lithium potassium brine

Immunoproteomic analysis of whole proteins from male and female adult Haemonchus contortus

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Immunoproteomic analysis of whole proteins from male and fem...