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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

Feasibility of bioleaching combined with Fenton oxidation to improve sewage sludge dewaterability

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Journal of Environmental Sciences 2015年第2期27卷 37-42页

作者： Changgeng Liu Panyue Zhang Chenghua Zeng Guangming Zeng Guoyin Xu Yi Huang School of Resources and Environmental Engineering Panzhihua University Key Laboratory of Environmental Biology and Pollution Control (Hunan University) Ministry of Education College of Environmental Science and Engineering Hunan University

A novel joint method of bioleaching with Fenton oxidation was applied to condition sewage sludge. The specific resistance to filtration（SRF） and moisture of sludge cake（MSC） were adopted to evaluate the improvement of sludge dewaterability. After 2-day bioleaching, the sludge p H dropped to about 2.5 which satisfied the acidic condition for Fenton ***, the SRF declined from 6.45 × 1010 to 2.07 × 1010s2/g, and MSC decreased from91.42% to 87.66%. The bioleached sludge was further conditioned with Fenton oxidation. From an economical point of view, the optimal dosages of H2O2 and Fe2＋were 0.12 and 0.036 mol/L,respectively, and the optimal reaction time was 60 min. Under optimal conditions, SRF,volatile solids reduction, and MSC were 3.43 × 108s2/g, 36.93%, and 79.58%, respectively. The stability and settleability of sewage sludge were both improved significantly. Besides,the results indicated that bioleaching-Fenton oxidation was more efficient in dewatering the sewage sludge than traditional Fenton oxidation. The sludge conditioning mechanisms by bioleaching-Fenton oxidation might mainly include the flocculation effects and the releases of extracellular polymeric substances–bound water and intercellular water.

关键词： Sewage sludge bioleaching Fenton oxidation Dewaterabilty

bioleaching of two different types of chalcopyrite by Acidithiobacillus ferrooxidans

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International Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 119-124页

作者： Ying-bo Dong Hai Lin Kai-bin Fu Xiao-fang Xu Shan-shan Zhou Key Laboratory of High-Efficient Mining and Safety of Metal Mines (Ministry of Education) University of Science and Technology Beijing School of Civil and Environmental Engineering University of Science and Technology Beijing

Two different types of chalcopyrite （pyritic chalcopyrite and porphyry chalcopyrite） were bioleached with AcidithiobaciUus ferrooxidans ATF6. The bioleaching of the pyritic chalcopyrite and porphyry chalcopyrite is quite different. The copper extraction reaches 46.96% for the pyritic chalcopyrite after 48-d leaching, but it is only 14.50% for the porphyry chalcopyrite. Proper amounts of initial ferrous ions can improve the efficiency of copper extraction for the two different types of chalcopyrite. The optimum dosage of ferrous ions for the pyritic chalcopyrite and porphyry chalcopyrite is different. The adsorption of ATF6 on the pyritic chalcopyrite and porphyry chalcopyrite was also studied in this paper. It is found that ATF6 is selectively adsorbed by the two different types of chalcopyrite; the higher adsorption onto the pyritic chalcopyrite than the porphyry chalcopyrite leads to the higher copper dissolution rate of the pyritic chalcopyrite. In addition, the zeta-potential of chalcopyrite before and after bioleaching further confirms that ATF6 is more easily adsorbed onto the pyritic chalcopyrite.

关键词： chalcopyrite bioleaching adsorption functional groups

bioleaching of zinc from gold ores using Acidithiobacillus ferrooxidans

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International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 368-374页

作者： Pakawadee Kaewkannetra Francisco Jose Garcia-Garcia Tze Yen Chiu Department of Biotechnology Faculty of TechnologyKhon Kaen University Corrosion and Protection Centre School of MaterialsThe University of Manchester Centre of Water Science Cranfield University

The present work investigated microbial leaching of zinc from ore using Acidithiobacillus ferrooxidans （ATCC 14859）. The ore samples, consisted of 13wt% zinc, were obtained from a gold mine in north-eastern Thailand. A shake flask study was performed on the ore samples using a rotary shaker under the following fixed conditions （250 r·min^-1, 30℃ for 16 d）. The influence of various conditions, namely medium type （with and without iron）, particle ore size （〈20, 20-40, 40-60, 60-100, and 〉100 mesh）, ore density （20 kg·m^-3, 50 kg·m^-3, and 100 kg·m^-3）, and pH of the medium （2, 2.5, 2.8, and 3）, were investigated. The microbial leaching was assessed by determining the concentration of zinc in the medium and compared with the initial sample concentration. The results show that Acidithiobacillus ferrooxidans can successfully leach zinc by as much as 6 times compared with the control experiment （without Acidithiobacillus ferrooxidans ferrooxidans）. The maximum efficiency （92.3%） for microbial leaching is obtained in iron-containing medium, 20-40 mesh ore sizes, 20 kg·m^-3 ore density at pH 2.8, and the zinc content is found in the medium at about 120 mg·m^-1.

关键词： bioleaching Acidithiobacillusferrooxidans gold ores gold mine

bioleaching of vanadium from stone coal vanadium ore by Bacillus mucilaginosus:Influencing factors and mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第8期31卷 1828-1838页

作者： Yingbo Dong Jinyu Zan Hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

Vanadium and its derivatives are used in various industries,including steel,metallurgy,pharmaceuticals,and aerospace *** China has massive reserves of stone coal resources,these resources have low ***,the effective extraction and recovery of metallic vanadium from stone coal is an important way to realize the efficient resource utilization of stone coal vanadium ***,Bacillus mucilaginosus was selected as the leaching *** vanadium leaching rate reached 35.5%after 20 d of bioleaching under optimal operating *** cumulative vanadium leaching rate in the contact group reached 35.5%,which was higher than that in the noncontact group(9.3%).The metabolites of ***,such as oxalic,tartaric,citric,and malic acids,dominated in bioleaching,accounting for 73.8%of the vanadium leaching ***,during leaching,the presence of stone coal stimulated the expression of carbonic anhydrase in bacterial cells,and enzyme activity increased by 1.335-1.905 *** activity positively promoted the production of metabolite organic acids,and total organic acid content increased by 39.31 mg·L^(-1),resulting in a reduction of 2.51 in the pH of the leaching system with stone *** effect favored the leaching of vanadium from stone *** force microscopy illustrated that bacterial leaching exacerbated corrosion on the surface of stone coal beyond 10 *** study provides a clear and promising strategy for exploring the bioleaching mechanism from the perspective of microbial enzyme activity and metabolites.

关键词： Bacillus mucilaginosus stone coal vanadium ore bioleaching carbonic anhydrase organic acids

bioleaching and biosorption behavior of vanadium-bearing stone coal by Bacillus mucilaginosus

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International Journal of Minerals,Metallurgy and Materials 2023年第2期30卷 283-292页

作者： Yingbo Dong Shijia Chong Hai Lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The recovery of vanadium(V)from stone coal by bioleaching is a promising *** bioleaching experiments and the biosorption experiments were carried out,aiming to explore the adsorption characteristics of Bacillus mucilaginosus(***)on the surface of vanadium-bearing stone coal,and the related mechanisms have been *** bioleaching at 30℃ for 28 d,the cumulative leaching rate of V reached 60.2%.The biosorption of *** on stone coal was affected by many *** the pH value of leaching system is 5.0,strong electrostatic attraction between bacteria and stone coal promoted *** in the logarithmic growth phase had mature and excellent biosorption *** initial bacterial concentration of 3.5×10^(8) CFU/mL was conducive to adhesion,with 38.9%adsorption rate and 3.6×10^(7) CFU/g adsorption *** adsorption of *** on the stone coal conformed to the Freundlich model and the pseudo-second-order kinetic *** surface carried functional groups(-CH_(2),-CH_(3),-NH_(2),etc.),which were highly correlated with the adsorption *** addition,biosorption changed the surface properties of stone coal,resulting in the isoelectric point(IEP)approaching the *** results could provide an effective reference for the adsorption laws of bacteria on minerals.

关键词： Bacillus mucilaginosus vanadium-bearing stone coal bioleaching biosorption

bioleaching of vanadium from barren stone coal and its effect on the transition of vanadium speciation and mineral phase

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 253-261页

作者： Xin Wang Hai Lin Ying-bo Dong Gan-yu Li School of Civil and Resource Engineering University of Science and Technology Beijing Beijing 100083 China School of Energy and Environmental Engineering University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083 China

This study determined the optimal conditions required to obtain maximum vanadium extraction and examined the transition of mineral phases and vanadium speciation during the bioleaching process. Parameters including the initial p H value, initial Fe^(2+) concentration, solid load, and inoculum quantity were examined. The results revealed that 48.92 wt% of the vanadium was extracted through bioleaching under optimal conditions. Comparatively, the chemical leaching yield(H_2SO_4, pH 2.0) showed a slower and milder increase in vanadium yield. The vanadium bioleaching yield was 35.11 wt% greater than the chemical leaching yield. The Community Bureau of Reference(BCR) sequential extraction results revealed that 88.62 wt% of vanadium existed in the residual fraction. The bacteria substantially changed the distribution of the vanadium speciation during the leaching process, and the residual fraction decreased to 48.44 wt%. The X-ray diffraction(XRD) and Fourier transform infrared(FTIR) results provided evidence that the crystal lattice structure of muscovite was destroyed by the bacteria.

关键词： bioleaching stone coal BCR-sequential extraction vanadium speciation mineral phase

bioleaching of copper oxide ore by P seudomonas aeruginosa

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International Journal of Minerals,Metallurgy and Materials 2013年第12期20卷 1130-1133页

作者： M.A.Shabani M.Irannajad A.R.Azadmehr M.Meshkini Department of Mining & Metallurgical Engineering Amirkabir University of Technology Iranian Academic Center for Education Culture and Research (ACECR)Branch of Amirkabir

bioleaching is an environmentally friendly method for extraction of metal from ores. In this study, bioleaching of copper oxide ore by Pseudomonas aeruginosa was investigated. Pseudomonas aeruginosa is a heterotrophic bactermm that can produce various organic acids in an appropriate culture medium, and these acids can operate as leaching agents. The parameters, such as particle size, glucose percentage in the culture medium, bioleaching time, and solid/liquid ratio were optimized. Optimum bioleaching conditions were found as follows： particle size of 150-177 μm, glucose percentage of 6%, bioleaching time of 8 d, and solid/liquid ratio of 1：80. Under these conditions, 53% of copper was extracted.

关键词： copper ore treatment copper oxides bioleaching organic acids heterotrophic bacteria Pseudomonas aeruginosa

bioleaching of copper from pre and post thermally activated low grade chalcopyrite contained ball mill spillage

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Frontiers of Environmental Science & Engineering 2013年第2期7卷 281-293页

作者： Sandeep PANDA Nilotoala PRADHAN Umaballav MOHAPATRA Sandeep K. PANDA Swagat S.RATH Danda S. RAO Bansi D. NAYAK Lala B. SUKLA Barada K. MISHRA CSIR-Institute of Minerals and Materials Technology Bhubaneswar 751013 India Department of Botany North Orissa University Baripada 757003 India Regional Center of Central Tuber Crops Research Institute Bhubaneswar 751019 India

bioleaching of a low grade chalcopyrite （ball mill spillage material） was tested for copper recovery in shake flasks. The original samples （as received） were thermally activated （600℃, 30 min） to notice the change in physico-chemical and mineralogical characteristics of the host rock and subsequently its effect on copper recovery. A mixed culture of acidophilic chemolithotrophic bacterial consortium predominantly entailing Acidithiobacillus fer- rooxidans strain was used for bioleaching studies and optimization of process parameters of both original and thermally activated samples. Mineralogical characteriza- tion studies indicated the presence of chalcopyrite, pyrite in the silicate matrix of the granitic rock. Field emission scanning electron microscopy coupled with Energy dispersive spectroscopy （FESEM-EDS） and X-ray Fluor- escence （XRF） analysis indicated mostly SiO2. With pH 2, pulp density 10% w/v, inoculum 10% v/v, temperature 30~C, 150 ***-~, 49% copper could be recovered in 30 days from the finest particle size （- 1 ~ 0.75 mm） of the original spillage sample. Under similar conditions 95% copper could be recovered from the thermally activated sample with the same size fraction in 10 days. The study revealed that thermal activation leads to volume expansion in the rock with the development of cracks, micro and macro pores on its surface, thereby enabling bacterial solution to penetrate more easily into the body, facilitating enhanced copper dissolution.

关键词： ball mill spillage thermal activation bioleaching copper