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可见光和银离子对p型和n型黄铜矿生物浸出的影响机理

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Transactions of Nonferrous Metals Society of China 2024年第2期34卷 655-668页

作者：赵春晓王军刘洋廖蕤杨宝军邱冠周中南大学资源加工与生物工程学院生物冶金教育部重点实验室长沙410083

研究可见光和银离子(Ag^(+))对嗜酸氧化亚铁硫杆菌浸出p型和n型黄铜矿(黄铜矿A和黄铜矿B)的不同影响及机理。通过霍尔效应试验、生物浸出试验、X射线衍射、扫描电子显微镜和X射线光电子能谱对黄铜矿的半导体性质、生物浸出行为、表面形... 详细信息

研究可见光和银离子(Ag^(+))对嗜酸氧化亚铁硫杆菌浸出p型和n型黄铜矿(黄铜矿A和黄铜矿B)的不同影响及机理。通过霍尔效应试验、生物浸出试验、X射线衍射、扫描电子显微镜和X射线光电子能谱对黄铜矿的半导体性质、生物浸出行为、表面形貌、主要物相和表面物种进行分析。实验结果表明,黄铜矿A比黄铜矿B具有更高的载流子浓度和更大的载流子迁移率,因此其溶出速率更快。生物浸出24 d后,当光照和Ag^(+)同时存在时,黄铜矿A的铜浸出率为91.05%,比黄铜矿B的铜浸出率(73.19%)高17.86%。显然,可见光和Ag^(+)对黄铜矿A生物溶解过程的促进作用强于黄铜矿B,这主要归因于黄铜矿A具有更高的载流子迁移率。此外,在光照影响下,黄铜矿表面电荷转移加快,导致Ag2S积累增多(特别是黄铜矿A),从而导致钝化层致密结构被破坏,钝化效果降低,黄铜矿溶解加速。

关键词：嗜酸氧化亚铁硫杆菌霍尔效应半导体性质光照黄铜矿生物浸出

Grain Growth Kinetics of BaTiO3 Nanocrystals During Calcining Process

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Chinese Journal of Chemical Physics 2008年第3期21卷 295-300页

作者： Xiao-lan Song Xi He Hai-ping Yang Yi-xin Qu guan-zhou qiu School of Resources Processing and BioenEineerinE Central South University Changsha 410083China College of Chemical Engineering Beijing University of Chemical Technology Beiging 100029China

BaTiO3 nanocrystals were synthesized by sol-gel method using barium acetate （Ba（CH3COO2） and tetrabutyl titanate （Ti（OC4H9）4） as raw materials. Xerogel precursors and products were characterized by means of thermogravimetric/differential scanning calorimetry （TG/DSC）, X-ray diffraction （XRD） and transmission electron microscope （TEM）. The influence of the calcination temperature and duration on the lattice constant, the lattice distortion, and the grain size of BaTiO3 nanocrystals was discussed based on the XRD results. The grain growth kinetics of BaTiO3 nanocrystals during the calcination process were simulated with a conventional grain growth model which only takes into account diffusion, and an isothermal model proposed by Qu and Song, which takes into account both diffusion and surface reactions. Using these models, the pre-exponential factor and the activation energy of the rate constant were estimated. The simulation results indicate that the isothermal model is superior to the conventional one in describing the grain growth process, implying that both diffusion and surface reactions play important roles in the grain growth process.

关键词： BaTiO3 nanocrystal Sol-gel method Grain growth kinetics

嗜酸氧化亚铁硫杆菌作用下含黄铁矿废石的生物溶解和动力学

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Transactions of Nonferrous Metals Society of China 2024年第7期34卷 2342-2353页

作者：洪茂鑫王军杨宝军刘洋廖甤于世超刘仕统汤安妮王炜邱冠周中南大学资源加工与生物工程学院长沙410083 中南大学生物冶金教育部重点实验室长沙410083 生态环境部华南环境科学研究所广州510655

使用生物淋洗处理黄铁矿废石,从源头上缓解其产生酸性矿山废水(AMD)的风险。生物淋洗结果显示,在嗜酸氧化亚铁硫杆菌(***)的作用下,40天内可以从黄铁矿废石中去除近82%的铁和硫。动力学研究结果表明,废石中黄铁矿的去除主要受化学反应... 详细信息

使用生物淋洗处理黄铁矿废石,从源头上缓解其产生酸性矿山废水(AMD)的风险。生物淋洗结果显示,在嗜酸氧化亚铁硫杆菌(***)的作用下,40天内可以从黄铁矿废石中去除近82%的铁和硫。动力学研究结果表明,废石中黄铁矿的去除主要受化学反应和内扩散控制。X射线衍射(XRD)和X射线光电子能谱(XPS)的结果表明,在***细菌介导下,生物源黄钾铁矾能够钝化废石中残余的黄铁矿。对渣样进行二次生物浸出,试验发现溶液pH没有明显下降,且仅有8 mg/L和160mg/L的铁从两个黄铁矿废石渣样中溶出,表明渣样的酸和铁释放能力得到削弱。

关键词：酸性矿山废水黄铁矿生物浸出矿山废弃物黄钾铁矾生物钝化

Flotation behavior and mechanism of rutile with nonyl hydroxamic acid

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Rare Metals 2016年第5期35卷 419-424页

作者： Jun Wang Hong-Wei Cheng Hong-Bo Zhao Wen-Qing Qin guan-zhou qiu School of Minerals Processing and Bioengineering Central South University

The flotation and surface interaction of rutile with nonyl hydroxamic acid were investigated in this work. The results show that the adsorption density and flotation recovery of rutile have similar tendency, especially the maximum recovery and adsorption occur at pH about 7.5. In terms of Fourier transform infrared（FTIR） spectroscopic analysis, chemical adsorption is identified on the surface of rutile, where a chelate of O,O-five-membered rings with Ti^4＋ on the surface of rutile may form. Adsorption measurements, Zeta potential test, IR spectrum analyses, and solution chemistry calculations illustrate that the adsorption on the rutile surface involves both physical and chemical adsorption, while chemical adsorption is dominant.

关键词： Rutile Flotation Nonyl hydroxamic acid Chelate

Mechanism of vanadic titanomagnetite solid-state reduction

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Rare Metals 2020年第11期39卷 1348-1352页

作者： Shui-Shi Liu Yu-Feng Guo guan-zhou qiu Tao Jiang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083China

The influence mechanism of vanadic titanomagnetite solid-state reduction was studied in this *** microscopy(OM),scanning electron microscope(SEM),and X-ray diffraction(XRD)were used to characterize the structure and phases of the *** results show that the dense structure is not the reason that limits the reducibility of Panxi vanadic *** rate of 93%was achieved when it was reduced at 1100℃for 100 *** pre-oxidation,Fe_(9)TiO_(15)and Fe_(2)O_(3)are the main phases of ***-oxidation could destroy the dense structure of vanadic titanomagnetite and increase the specific surface area of ***,reducibility of vanadic titanomagnetite is not improved obviously by pre-oxidation,with metallization rate increasing only 1%under the same reduction conditions,and the generated metallic iron grains are *** transformation of vanadic titanomagnetite at different reduction temperatures shows that the presence of FeTi_(2)O_(5)is the main reason that limits the reducibility of Panxi vanadic titanomagnetite.

关键词： Vanadic titanomagnetite Pre-oxidation Solid-state reduction Reduction process

Reduction roasting–magnetic separation of vanadium tailings in presence of sodium sulfate and its mechanisms

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Rare Metals 2016年第12期35卷 954-960页

作者： Yu-Lei Sui Yu-Feng Guo Andrew Yakovlevich Travyanov Tao Jiang Feng Chen guan-zhou qiu School of Minerals Processing and Bioengineering Central South University Institute of Environmental Technology and Engineering National University of Science and Technology ‘‘MISi S’’

Reduction roasting with sodium sulfate fol- lowed by magnetic separation was investigated to utilize vanadium tailings with total iron grade of 54.90 wt% and TiO2 content of 17.40 wt%. The results show that after reduction roasting-magnetic separation with sodium sul- fate dosage of 2 wt% at roasting temperature of 1150℃ for roasting time of 120 min, metallic iron concentrate with total iron grade of 90.20 wt%, iron recovery rate of 97.56 % and TiO2 content of 4.85 wt% is obtained and high-titanium slag with TiO2 content of 57.31 wt% and TiO2 recovery rate of 80.27 % is also obtained. The results show that sodium sulfate has a catalytic effect on the reduction of tailings in the novel process by thermody- namics, scanning electron microscopy （SEM） and X-ray diffraction （XRD） and reacts with silica and alumina in the tailings to form sodium silicate and sodium aluminosili- cate. Migration of elements and chemical reactions destroy the crystal structures of minerals and promote the reduction of vanadium tailings, resulting in that iron grains grow to large size so that metallic iron concentrate with high total iron grade and low TiO2 content is obtained.

关键词： Vanadium tailings Reduction roasting Sodium sulfate Fe-Ti separation

Bioleaching of chalcopyrite and bornite by moderately thermophilic bacteria: an emphasis on their interactions

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International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 777-787页

作者： Hong-bo Zhao Jun Wang Xiao-wen Gan Wen-qing Qin Ming-hao Hu guan-zhou qiu School of Minerals Processing & Bioengineering Central South University Key Lab of Bio-hydrometallurgy of the Ministry of Education

Interactions between chalcopyrite and bornite during bioleaching by moderately thermophilic bacteria were investigated mainly by X-ray diffraction, scanning electron microscopy, and electrochemical measurements performed in conjunction with bioleaching experiments. The results showed that a synergistic effect existed between chalcopyrite and bornite during bioleaching by both Acidithiobacillus caldus and Leptospirillum ferriphilum and that extremely high copper extraction could be achieved when chalcopyrite and bornite coexisted in a bioleaching system. Bornite dissolved preferentially because of its lower corrosion potential, and its dissolution was accelerated by the galvanic current during the initial stage of bioleaching. The galvanic current and optimum redox potential of 390-480 m V vs. Ag/Ag Cl promoted the reduction of chalcopyrite to chalcocite(Cu2S), thus accelerating its dissolution.

关键词： chalcopyrite bornite bioleaching interactions redo

Transformation and separation of metallic iron in reduced ilmenite during corrosion process

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Journal of Iron and Steel Research International 2020年第12期27卷 1372-1381页

作者： Fu-qiang Zheng Xia Liu Yu-feng Guo Shuai Wang Feng Chen Ling-zhi Yang Tao Jiang guan-zhou qiu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Hunan Qingzhiyuan Environmental Protection Technology Co. Ltd.Changsha 410083HunanChina

The effects of corrosion temperature, oxygen flow rate and corrosion time on the transformation of metallic iron were systematically studied, and the effects of mineral phases of Fe-bearing products on Ti-Fe separation were investigated. The reaction mechanism of metallic iron in corrosion process was proposed. The results showed that corrosion temperature played a key role in determining the transformation of metallic iron in reduced ilmenite during corrosion process. Under suitable corrosion conditions, Fe-bearing mineral in reduced ilmenite could be converted to amorphous ferric hydroxide, lepidocrocite,hematite and magnetite, respectively, and lepidocrocite was the most easily separated Fe-bearing mineral from corrosion products owing to the significant density difference between lepidocrocite and Ti-rich materials. The Ti-rich material with 77.81 wt.% TiO2 and Fe-bearing product with 52.69 wt.% total Fe were obtained by gravity separation. The Ti recovery ratio and Fe recovery ratio were 91.16% and 86.27%, respectively.

关键词： Reduced ilmenite Corrosion Ti-rich material Fe-bearing mineral Lepidocrocite Metallic iron

Biotech key to unlock mineral resources value

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Transactions of Nonferrous Metals Society of China 2022年第7期32卷 2309-2317页

作者： guan-zhou qiu Xue-duan LIU School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Biometallurgy of Ministry of Education Central South UniversityChangsha 410083China

This work aims to describe the history of biometallurgy in China,introduce the development and application of biometallurgy technologies in exploitation of mineral resources,and identify the main challenges and future *** the earliest biometallurgy activities in China were documented in 6th−7th century BC,fundamental research and biometallurgy applications started relatively late in this *** development,from phenotypic to genotypic characterization of biometallurgy microorganisms,as well as from theoretical to practical applications,has been made in China since the *** integrated applications of biometallurgy technology in copper,gold,and uranium extraction ensured China’s economic reserves of strategic mineral *** more efficient microorganisms and strengthening the micro-interface reactions will be an effective way to improve the biometallurgy *** technologies can also be adapted to recovery of valuable metal from marine minerals and e-wastes and environmental protection including carbon sequestration and heavy metal polluted soil/sediment bioremediation.

关键词： biotechnology biometallurgy bioleaching mineral resources nonferrous metals