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Tungsten 2025年第1期7卷 80-87页

作者： Fang-Qian Wang Yin Zhang Wei-Wei Wang Mei-Qian Fu Hong-Bing Mo Wei-Dong Yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates vanadium

vanadium(Ⅳ)solvent extraction enhancement in high acidity using di-(2-ethylhexyl)phosphoric acid with[Cl^(-)]present:an experimental and theoretical study

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Frontiers of Chemical Science and Engineering 2023年第1期17卷 56-67页

作者： Hong Liu Yi-Min Zhang Jing Huang Tao Liu School of Resource and Environmental Engineering Wuhan University of Science and TechnologyWuhan 430081China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control Wuhan University of Science and TechnologyWuhan 430081China Hubei Collaborative Innovation Center for High Efficient Utilization of vanadium Resources Wuhan University of Science and TechnologyWuhan 430081China Hubei Provincial Engineering Technology Research Center of High Efficient Cleaning Utilization for Shale vanadium Resource Wuhan University of Science and TechnologyWuhan 430081China

Separation of vanadium from black shale leaching solution at low pH is very meaningful,which can effectively avoid the generation of alkali neutralization slag and the resulting vanadium *** this study,coordination mechanism of vanadium in acid leaching solution at low pH was investigated with the intervention of chloride *** the conditions of pH 0.8,di-(2-ethylhexyl)phosphoric acid concentration of 20%,phase ratio of 1:2,and extraction time of 8 min,the vanadium extraction could reach 80.00%.The Fourier transform infrared and electrospray ionization results reveal that,despite the fact that the chloride ion in the leachate could significantly promote vanadium extraction,the chloride ion does not enter the organic phase,indicating an intriguing *** Cl^(-)-V,SO_(4)^(2-)-V,and H_(2)O-V,the V-Cl bond is longer and the potential difference between coordinate ions and vanadium is ***,Vo^(2+)gets easily desorbed with chloride ions and enter the organic *** the same time,the hydrogen ions of di-(2-ethylhexyl)phosphoric acid also enter the water phase more easily,which reduces the pH required for the extraction reaction.

关键词： vanadium black shale solvent extraction high acidity extraction

vanadium(V)reduction by using a by-product of the yellow phosphorus industry

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Chinese Journal of Chemical Engineering 2023年第10期62卷 150-158页

作者： Baibin Yang Shihong Chen Haowen Ren Yang Qiu Chong Chen Yong Guo Chunhui Luo Qiang Zhao Wei Yang School of Chemical Engineering Sichuan UniversityChengdu 610065China State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource&HydropowerSichuan UniversityChengdu 610065China

Release of vanadium(V)from industry has threatened the environment and human *** this paper,a removal method of vanadium(V)is proposed using a by-product of the yellow phosphorus industry(phosphorus-iron)as a reducing *** thermodynamics analysis shows that the Gibbs free energy is always negative from 0 to 100℃,indicating a spontaneous *** of the phosphorus-iron slag/sulfuric acid dosage and temperature on the removal efficiency is comprehensively studied,and the kinetics parameters are calculated based on a quasi-first order reaction kinetics *** indicate that vanadium(V)can be entirely reduced by using phosphorus-iron slag,the frequency factor and apparent activation energy are 3.23×10^(9)min^(-1)and 64.50 ***^(-1) for vanadium(V)*** on above results,a lab-scale reactor is constructed and achieves a removal efficiency of~100%and a treatment capacity of 200 ml vanadium(V)solution(2 g.L^(-1))within 3 *** work demonstrates the feasibility of vanadium(V)reduction using phosphorus-iron slag as a reducing agent in applications.

关键词： vanadium Phosphorus-iron slag Thermodynamics Kinetics Reduction

vanadium recovery from clay vanadium mineral using an acid leaching method

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Rare Metals 2008年第2期27卷 116-120页

作者： LI Haoran FENG Yali LIANG Jianglong LUO Xiaobing DU Zhuwei State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China

A technique including direct acid leaching, vanadium precipitation with alkaline, sodium hydroxide releaching, impurity removing by adjusting pH value, precipitation vanadium with ammonium chloride, and vanadium pentoxide by roasting steps was proposed according to the characteristic of Xichuan clay vanadium mineral. The factors influencing leaching vanadium such as temperature and the concentration of sulfuric acid were investigated and optimized. The experimental results indicate that the extract ratios of V205 can reach 94% and 92% at a sodium chlorate ratio of 3% and a manganese dioxide ratio of 3%, respectivdy. A completely chemical precipitation method was adopted to decontaminate and enrich the vanadium in the acid leaching solution. The X-ray diffraction （XRD） pattern and the purity analysis of vanadium pentoxide indicate that the purity of final vanadium pentoxide can reach 99% and meet the standard specifications. The total recovery can reach about 75%. The technique has the characteristics of simplicity, less investment, and more environment safety as compared with the traditional salt roasting method.

关键词： clay vanadium mineral vanadium extraction acid leaching vanadium pentoxide

vanadium and molybdenum concentrations in particulate from Palermo （Italy）： analytical methods using voltammetry

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Frontiers of Environmental Science & Engineering 2015年第4期9卷 605-614页

作者： Diana AMORELLO Santino ORECCHIO Department of Biological Chemical and Pharmaceutical Sciences and Technologies Palermo University Palermo 1-90128 Italy

The main purpose of this work was to develop a reliable method for the determination of vanadium （V） and molybdenum （Mo） in atmosphere particles or aerosols because they can not be readily measured using conventional techniques. For this research, 30 particulate samples were collected from five different stations located at Palermo, Italy. We used the catalytic adsorptive stripping voltammetry and differential pulsed voltammetry to measure V and Mo in atmospheric particulate, respectively. The represented method includes advantages of high sensitivity, high selectivity, simplicity, reproducibility, speed and low costs. The quantification limits for V and Mo are, respectively, 0.57 and 0.80 ng·m^-3. The precision, expressed as relative standard deviation （RSD %）, was about 2% for both metals. The mean recoveries of added V and Mo were about 99.5% and ranged from 97% to 101%. vanadium concentrations in particulate samples collected in Palermo area ranged from 0.57 to 7.7 ng·m^-3, while Mo concentrations were in the range 0.8–51 ng·m^-3. In many cases the concentrations of two elements in the particulate samples fall below the detection limits. The mean concentrations for V and Mo in particulate samples, collected in Palermo area, were respectively 3.1 and 5.9 ng·m^-3.

关键词： vanadium molybdenum particulate voltammerry Palermo

A new process of extracting vanadium from stone coal

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 381-388页

作者： Yan-hua Liu Chao Yang Pei-you Li Shi-qi Li Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China Beijing Nengtai Environmental Protection Group Corp Beijing 100022 China

A new process of extracting vanadium from the stone coal vanadium ore in Fangshankou, Dtmhuang area of Gansu Province, China was introduced. Various leaching experiments were carried out, and the results show that the vanadium ore in Fangshankou is difficult to process due to its high consumption of acid and the high leaching rate of impurities. However, the leaching rate can be up to 80% and the content of V2O5 in the residue can be between 0.22%-0.25% in the process of ore fme grinding→oxidation roasting→mixing and ripening→aqueous leaching→P2O4 solvent extraction→sulfuric acid stripping→oxidation and precipitation→decomposition by heat. Also, the quality of flaky V205 produced by this process can meet the requirements of GB3283--87. The total leaching rate of vanadium is 70%. Also, three types of wastes are easy to treat. The vanadium extraction process is better in relation to the aspect of environmental protection than the sodium method.

关键词： stone coal vanadium extraction leaching solvent extraction V2O5

Catalytic-kinetic spectrophotometric determination of vanadium (V) based on the Celestine blue-bromate-vanadium (V)-citric acid reaction

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Rare Metals 2011年第4期30卷 348-358页

作者： Ramazan Gürkan Olcay Gürkan Department of Chemistry Faculty of Sciences University of Cumhuriyet Sivas Fen Lisesi Emek mah. 64. Basari Sok. TR-58010 Merkez Sivas TURKEY

A novel sensitive and relatively selective kinetic method is presented for the determination of V（V） based on its catalytic effect on the oxidation reaction of Celestine blue by potassium bromate in the presence of citric acid as an activator. The reaction was monitored spectropho- tometrically by measuring the decrease in absorbance of Celestine blue at a maximum absorption wavelength of 540 nm between 0.5 and 9 min （the fixed-time method） in an H3PO4 medium at 45℃. The effect of various parameters such as concentrations of H3PO4, citric acid, potassium bromate and Celestine blue, ionic strength, reaction temperature and time on the rate of V（V） catalyzed reaction was studied. The method is free from the most interferences, especially from large amounts of V（IV）. The decrease in absorbance is proportional to the concentration of V（V） over the entire concentration range tested （0.025-1.25 ***^-1） with a detection limit of 6.80 tag.L^-1 （according to statistical 3Sblank/k criterion） and a coefficient of variation （CV） of 1.78% （for ten replicate measurements at 95% confidence level）. The proposed method suffers from a few interferences such as Cr（VI） and Hg（Ⅱ） ions. The method was successfully applied to the determination of V（V） in river water, lake water, tap water, natural drinking water samples and a certified standard reference material such as SRM-1640 with satis- factory results. The vanadium contents of natural water samples were detected by using both linear calibration curve and standard addition curve methods. The recoveries of spiked vanadium （V） into the certified standard water sample were found to be quantitative, and the reproducibility was satisfactory. It was observed that the results of the SRM 1640 were in good agreement with the certified value.

关键词： catalytic effect vanadium spectrophotometry bromates Celestine blue citric acid

Mechanisms of aid-leaching reagent calcium fluoride in the extracting vanadium processes from stone coal

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Rare Metals 2013年第1期32卷 57-62页

作者： Fei Wang Yi-Min Zhang Jing Huang Tao Liu Yi Wang Xiao Yang Jie Zhao College of Resources and Environmental Engineering Wuhan University of Science and Technology

The mechanisms of aid-leaching reagent calcium fluoride in the extracting vanadium processes were researched by comparing the blank extraction with the extraction with calcium fluoride as aid-leaching reagent. The leaching experiments were carried out under the conditions of 95 ~C, 6 h, 1.5 ml.g-1, 15 vol % H2SO4, and 5 % calcium fluoride （mass ratio of CaF2 to stone coal）. The concentrations of hydrogen ion were adjusted from initial 1.82 and 4.79 mol.L-1 to the pH of 1.80 4- 0.05 by 200 g.L-1 lime milk, respectively. The solvent extraction experiments were carded out under the organic phase using 15 vol% D2EHPA, 5 vol% TBP, and 80 vol% sulfonated kerosene and O/A phase ratio of 1/4. The leaching rate of vanadium and six-stage countercurrent solvent extraction rate of vanadium can be remarkably improved from 66.71 to 92.97 % and 81.15 to 98.81%, respectively, when calcium fluoride was added as aid-leaching reagent. In the leaching process, fluorine can enhance the breakage of the structure of vanadium-bearing minerals. Meanwhile, fluoride ion can combine with iron ion to generate acid-insoluble iron fluoride hydrate （Fe2Fs.7H20） and consume all ferric ions and a portion of ferrous ions. In adjusting pH value process, the massive impurities are decreased to form KA1SO4 and FeA1Fs. In solvent extraction process, fluorine can prevent the formation of ferric hydroxide colloids and eliminate the formed unstable ferric hydroxide colloids and the silicon-containing colloids to promote the sufficient contact between the aqueous phase and the organic phase and the sufficient reaction.

关键词： vanadium Stone coal Aid-leaching reagent Calcium fluoride Mechanisms

Roasting and leaching behaviors of vanadium and chromium in calcification roasting–acid leaching of high-chromium vanadium slag

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 515-526页

作者： Jing Wen Tao Jiang Mi Zhou Hui-yang Gao Jia-yi Liu Xiang-xin Xue School of Metallurgy Northeastern University Liaoning Key Laboratory for Recycling Science of Metallurgical Resources

Calcification roasting–acid leaching of high-chromium vanadium slag(HCVS)was conducted to elucidate the roasting and leaching behaviors of vanadium and *** effects of the purity of Ca O,molar ratio between Ca O and V_2O_5(n(Ca O)/n(V_2O_5)),roasting temperature,holding time,and the heating rate used in the oxidation–calcification processes were *** roasting process and mechanism were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and thermogravimetry–differential scanning calorimetry(TG–DSC).The results show that most of vanadium reacted with Ca O to generate calcium vanadates and transferred into the leaching liquid,whereas almost all of the chromium remained in the leaching residue in the form of(Fe_(0.6)Cr_(0.4))_2O_*** trends of the vanadium and chromium leaching ratios were always opposite because of the competitive reactions of oxidation and calcification between vanadium and chromium with Ca ***,Ca O was more likely to combine with vanadium,as further confirmed by thermodynamic *** the HCVS with Ca O added in an n(Ca O)/n(V_2O_5)ratio of 0.5 was roasted in an air atmosphere at a heating rate of 10°C/min from room temperature to 950°C and maintained at this temperature for 60 min,the leaching ratios of vanadium and chromium reached91.14%and 0.49%,respectively;thus,efficient extraction of vanadium from HCVS was achieved and the leaching residue could be used as a new raw material for the extraction of ***,the oxidation and calcification reactions of the spinel phases occurred at 592and 630°C for n(Ca O)/n(V_2O_5)ratios of 0.5 and 5,respectively.

关键词： high-chromium vanadium slag calcification roasting roasting behaviors leaching behaviors vanadium extraction

Leaching behavior and mineralogical evolution of vanadium released from sodium roasted-acid leaching tailing of vanadium slag

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Journal of Iron and Steel Research International 2022年第5期29卷 772-782页

作者： Bao Liu Jin Li Qian-qian Ren Shuang Cai Xue Yang Ya-nan Zeng Jun-guo Li College of Metallurgy and Energy North China University of Science and TechnologyTangshan063210HebeiChina

The sodium roasted-acid leaching tailing(SRALT)of vanadium slag with a certain amount of vanadium exhibits potential environmental *** investigate the leaching behavior of vanadium from the SRALT,neutral batch leaching tests were *** evolution of vanadium concentration,pH,redox potential(Eh),dissolved oxygen,and conductivity as a function of time was *** diagrams of V–H2O system with different vanadium concentrations were obtained to identify the ionic speciation of vanadium in leachate.X-ray diffraction,X-ray photoelectron spectroscopy,field emission-scanning electron microscopy,and thermogravimetry–differential scanning calorimetry analysis were conducted to investigate the mineralogical evolution of the SRALT during the leaching *** was found that the major minerals of the original SRALT are titanomagnetite,spinel,olivine,and *** valence states of V existing in the original SRALT are V^(3+)and V^(5+).The pH and Eh values of the obtained leachates are 10.00–10.58 and(−43)–(+67)mV,*** this pH and Eh region,the released vanadium is mainly present as HVO_(4)^(2−).The FeOOH and CaCO_(3)would form during the leaching *** HVO_(4)^(2−)would be mainly adsorbed by the FeOOH and slightly incorporated into the CaCO_(3),resulting in the decline in the vanadium *** vanadium concentration above 27 mg L^(−1)and the dissolved oxygen value below 5.0 mg L^(−1)can be obtained after a short leaching *** a V(V)-releasing and oxygen-depleting substance,the leaching toxicity of the SRALT should not be ignored.

关键词： vanadium vanadium slag Tailing Leaching toxicity Mineralogical analysis