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Bioleaching of Ni-Cu Sulfide with Acidophilic Thermophile Acidianus brierleyi
极度嗜热菌Acidianus brierleyi浸出镍铜硫化矿精矿

ZHAO Yue-feng,FANG Zhao-heng,

过程工程学报 , 2003,
Abstract: 考察了极度嗜热菌Acildianus brierleyi在摇瓶中浸出金川镍铜硫化矿的工艺条件及添加物对浸出过程的影响.结果表明,初始pHl.2—1.6、细菌接种量10%-20%、低矿浆浓度、细矿石粒度(-48μm)有利于浸出过程的进行;在68℃、初始pH1.6、接种量10%、矿浆浓度5%条件下,4.5d后镍和铜可分别浸出99.78%和86.30%;添加酵母(0.005%-0.02%)及硫酸铁(1—5g/L可强化镍和铜的浸出.
Cyclic Voltammetry Analysis of Bioleaching of Low Grade Chalcopyrite by Thermophilic Acidianus brierleyi

LIU Dai-yun,WEI Zhen-dong,HUA Mei,LIU Hui-yong,

过程工程学报 , 2010,
Abstract: 电解液中含与不含布氏酸菌时,采用循环伏安法研究了黄铜矿-碳糊电极与电解液之间的电化学行为,并探讨了温度、阴极电位、Fe2+和Cu2+对循环伏安曲线的影响. 结果表明,低品位黄铜矿在0.45 V出现生成多硫化合物的氧化峰,在-0.25和-0.43 V出现生成Cu5FeS4和Cu2S的还原峰. 温度升高促进黄铜矿氧化分解,65℃时的峰电流为35℃时的2倍. 添加适量Fe2+和Cu2+能促进黄铜矿的氧化分解.
Bioleaching of chalcopyrite and bornite by moderately thermophilic bacteria: an emphasis on their interactions  [PDF]
Hong-bo Zhao,Jun Wang,Xiao-wen Gan,Wen-qing Qin,Ming-hao Hu,Guan-zhou Qiu
- , 2015, DOI: https://doi.org/10.1007/s12613-015-1134-7
Abstract: 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 mV vs. Ag/AgCl promoted the reduction of chalcopyrite to chalcocite (Cu2S), thus accelerating its dissolution.
Characteristics of Bioleaching of Zijin Copper Ore by Acidianus brierleyi

LI Cong-ying,MENG Chun,LIN Hui,CHEN Shou-qing,SUN Jie,GUO Yang-hao,ZOU Lai-chang,

过程工程学报 , 2004,
Abstract: 研究了布氏酸菌浸出紫金山铜矿过程的特性.考察了初始pH、接种量和矿浆浓度对浸出率的影响,表明布氏酸菌浸出的最佳操作条件为pH2.0、接种量10%、矿浆浓度5%.探讨了布氏酸菌的浸出机理,紫金山铜矿的浸出是细菌直接氧化和Fe^3 化学氧化复合作用的结果.布氏酸菌(65℃)对紫金山铜矿的浸出能力强,是氧化亚铁硫杆菌(31℃)的1.7倍,具有良好的工业应用前景.
Dissolution characteristics of sericite in chalcopyrite bioleaching and its effect on copper extraction  [PDF]
Ying-bo Dong,Hao Li,Hai Lin,Yuan Zhang
- , 2017, DOI: https://doi.org/10.1007/s12613-017-1416-3
Abstract: The effects of sericite particle size, rotation speed, and leaching temperature on sericite dissolution and copper extraction in a chalcopyrite bioleaching system were examined. Finer particles, appropriate temperature and rotation speed for Acidithiobacillus ferrooxidans resulted in a higher Al3+ dissolution concentration. The Al3+ dissolution concentration reached its highest concentration of 38.66 mg/L after 48-d leaching when the sericite particle size, temperature, and rotation speed were ?43 μm, 30°C, and 160 r/min, respectively. Meanwhile, the sericite particle size, rotation speed, and temperature can affect copper extraction. The copper extraction rate is higher when the sericite particle size is finer. An appropriately high temperature is favorable for copper leaching. The dissolution of sericite fitted the shrinking core model, 1–(2/3)α–(1–α)2/3 = k 1 t, which indicates that internal diffusion is the decision step controlling the overall reaction rate in the leaching process. Scanning electron microscopy analysis showed small precipitates covered on the surface of sericite after leaching, which increased the diffusion resistance of the leaching solution and dissolved ions.
Community structure and dynamics of moderately thermophilic microorganisms during bioleaching of low-grade chalcopyrite by column reactor

WANG Yu-Guang,ZHAO Wei,SU Li-Jun,LIU Fei-Fei,WU Chang-Bin,ZHOU Hong-Bo,

微生物学通报 , 2011,
Abstract: In this study, a mixed culture of moderately thermophilic microorganisms was enriched from several acid mine drainage samples collected from copper mines in China at 45 °C. The pH and copper concentration in the leachate were monitored during bioleaching low-grade chalcopyrite by column reactor, and community structure and dynamics were investigated by restriction fragment length polymorphism (RFLP). The results show that variation of pH was more obvious, and pH value was always higher than 1.8 in the bioleaching process. And 13.6% of copper was recovered within 60 days. RFLP results show that microbial community was dominated by L. ferriphilum in the initial stage, which occupied 81% of total prokaryotes. With the bioleaching process continues, the proportion of L. ferriphilum decreased slowly, which only had a proportion of 13% in the final stage. The proportion of S. thermotolerans and A. caldus were increase gradually, and the proportion was 32% and 23% respectively in the middle stage. S. thermotolerans was the dominant microorganism in the final stage, and the proportion was up to 79%. The research results could promote to understand bioleaching characteristics and behavior of moderately thermophilic microorganisms and provide referential experience for industrial application.
Biotic communities of the marine ecosystem in Meizhou Bay
Ren Jiuchang,Cai Xiaoming,
Ren Jiuchang
,Cai Xiaoming,Chen Bin,Li Peng,Chen Zhengjin,Li Jianshen

环境科学学报(英文版) , 1996,
Abstract: The current situation of biotic communities in Meizhou Bay is presented in this paper.The species composition,seasonal variation,and distribution of phytoplankton,zooplankton, red tide organisms,fishes,and benthos in Meizhou Bay were investigated,and the content of chlorophyll a and primary production and their seasonal variation were also determined.The water quality of Meizhou Bay was monitored by measuring the density of Escherichia coli. Results reveal that there is a great variety of species in Meizhou Bay and the water in Meizhou Bay is oligotrophic.But the individual numbers of various organisms are very low, especially those of algae.Moreover,there are more than 40 species of red tide organisms and there exist opportunities of red tides between May and November.All these demand cautious be taken in the future development of this area although it has great environment capacity.
Influence of acidophilic heterotrophic bacteria on metal resistance and bioleaching by Acidithiobacillus ferrooxidans
嗜酸异养菌对自养菌Acidithiobacillus ferrooxidans金属离子抗性和生物浸出的影响

LIU Hong-wei,DAI Yan-xi,HUANG Wei,YIN Hua-qun,LIANG Yi-li,Shen Li,LIU Xue-duan,

微生物学通报 , 2012,
Abstract: Objective] to investigate the influence of acidophilic heterotrophic bacteria on Acidithiobacillus ferrooxidans in extremely acidic environment such as acid mine drainage (AMD) and bioleaching system. Methods] a co-culture consists of Aph. acidophilum and At. ferrooxidans was separately exposed to four metal ions (Cd2+, Cu2+, Ni2+ and Mg2+) to test its stability. This co-culture was also applied to bioleaching of pyrite and low grade chalcopyrite. Results] In the metal resistance experiment, heterotrophic bacteria Aph. acidophilum facilitated the ferrous iron oxidation by At. ferrooxidans and improved its efficiency of energy utilization. The maximum tolerant concentration (MTC) of At. ferrooxidans to Cu2+ was improved from 2.0 g/L to 5.0 g/L by Aph. acidophilum, and the cell density of co-culture in 5.0?g/L Cu2+ was almost the same with purely cultured At. ferrooxidans in 2.0 g/L Cu2+. In addition, the MTC of co-cultured At. ferrooxidans to Mg2+ was also improved from 12.0 g/L to 17.0 g/L by Aph. acidophilum. In bioleaching experiment, the pyrite bioleaching efficiency of co-culture increased by 22.70% as compared with that of purely cultured At. ferrooxidans. While in the low grade chalcopyrite bioleaching system with few iron, the bioleaching efficiency of both At. ferrooxidans and its co-culture with Aph. acidophilum were lower than 33%. In the low grade chalcopyrite bioleaching system with pre-added 2 g/L Fe2+, the bioleaching efficiency of At. ferrooxidans and its co-culture with Aph. acidophilum were raised to 41.27% and 52.22%, respectively. Conclusion] Results in this study demonstrated that At. ferrooxidans and Aph. acidophilum in co-culture could maintain their physiological stability and sustain their ecological function under environmental stress. The bioleaching results suggested that acidophilic heterotrophic bacteria Aph. acidophilum should be applied to the bioleaching system with high iron concentration, in which it could collaborate with iron oxidation bacteria to improve the bioleaching efficiency.
Enhancement of Au–Ag–Te contents in tellurium-bearing ore minerals via bioleaching  [PDF]
Nag-Choul Choi,Kang Hee Cho,Bong Ju Kim,Soonjae Lee,Cheon Young Park
- , 2018, DOI: https://doi.org/10.1007/s12613-018-1569-8
Abstract: The purpose of this study was to enhance the content of valuable metals, such as Au, Ag, and Te, in tellurium-bearing minerals via bioleaching. The ore samples composed of invisible Au and Au paragenesis minerals (such as pyrite, chalcopyrite, sphalerite and galena) in combination with tellurium-bearing minerals (hessite, sylvanite and Tellurobismuthite) were studied. Indigenous microbes from mine drainage were isolated and identified as Acidithiobacillus ferrooxidans, which were used in bioleaching after adaption to copper. The effect of the microbial adaption on the bioleaching performance was then compared with the results produced by the non-adaptive process. The microbial adaption enhanced the Au–Ag–Te contents in biological leaching of tellurium-bearing ore minerals. This suggests that bioleaching with adapted microbes can be used both as a pretreatment and in the main recovery processes of valuable metals.
Nonlinear dissolution reaction of chalcopyrite
Kaixuan Tan,Xincai Hao,Tagen Dai
Chinese Science Bulletin , 1999, DOI: 10.1007/BF03182892
Abstract: The dissolution experiments of chalcopyrite in 2 mol/L NaCl solutions at 70°C show that the dissolution rate of chalcopyrite oscillates non-periodically with reaction time while in acid solutions (pH = 1.45–2.45) and far from Cu saturation concentration, and Cu concentration oscillates chaotically in solution of weak to intermediate acidity (pH = 3.66–7.0). In nonequilibrium and open systems, the nonlinear coupling between the dissolution of chalcopyrite and formation of cuprous chloride complexes and precipitation of hemitite caused by Cl , H+ and O2 is the internal mechanism of oscillatory changes of dissolution rate, and the nonlinear coupling between the dissolution of chalcopyrite and precipitation of atacamite induced by Cl and H+ has caused the chaotic oscillation of Cu concentration. There are consistence and difference between reaction rate oscillation and Cu concentration oscillation. However, both of them suggest that the dissolution of chalcopyrite in NaCl solution is a nonlinear reaction process.
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