The Experts below are selected from a list of 10452 Experts worldwide ranked by ideXlab platform
Wenqing Qin - One of the best experts on this subject based on the ideXlab platform.
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bioleaching of a low grade nickel copper cobalt Sulfide Ore
Hydrometallurgy, 2011Co-Authors: Congren Yang, Yansheng Zhang, Jun Wang, Wenqing Qin, Shaoshi Lai, Fen Jiao, Liuyi Ren, Tian Zhuang, Ziyong ChangAbstract:Abstract The bioleaching behavior of copper and nickel from a low-grade nickel, copper, and cobalt-bearing Sulfide Ore was investigated. A recovery of 94% Ni, 62% Co and 70% Cu was achieved in 68 days of flask leaching including 18 days of acid pre-leaching and 50 days of bioleaching. However, a recovery of 46% Ni, 39% Co and 13% Cu was achieved in 139 days of column leaching including 19 days of acid pre-leaching and 120 days of bioleaching which indicates that nickel and cobalt have the same leaching behavior. Potassium, sodium and iron(III) ions in the leach solution formed jarosite within the Ore bed with some nickel and copper ions incorporated into the jarosite precipitates thereby diminishing the overall metal recovery. Magnesium was preferentially leached by acid from the gangue minerals leaving a magnesium depleted silicate skeleton, but discrepancies in the residue analysis indicate that magnesium re-deposits into the silicate skeleton during bioleaching.
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heap bioleaching of a low grade nickel bearing Sulfide Ore containing high levels of magnesium as olivine chlorite and antigorite
Hydrometallurgy, 2009Co-Authors: Wenqing Qin, Jun Wang, Shijie Zhen, Zhongqiang Yan, Maurice Campbell, Kai Liu, Yansheng ZhangAbstract:Abstract This work investigates the heap bioleaching of a low-grade nickel Sulfide Ore containing rather high levels of olivine, chlorite and antigorite (MgO 30–35%) present in the main gangue minerals. A 500-ton heap bioleaching system was developed and the microorganisms used in the test were a mixture of mesophiles, Acidithiobacillus ferrooxidans ( DQ321745 ), Acidithiobacillus thiooxidans ( EF059760 ) and Leptospirillum ferrooxidans (DSM2391). The inoculum used was obtained from a three-stage progressive scale-up (from 25 L to 500 L and finally to 10 m 3 ) culture. Industrial grade concentrated sulfuric acid and acid wastewater (pH 0.0–0.3) produced from off-gas treating during the smelting process were also used during bioleaching. A nickel (84.6%) and cobalt (75.0%) extraction was achieved after 350 days of heap leaching, including 80 days of acid pre-leaching and 270 days of bioleaching. The economical feasibility model predicted that the process was feasible.
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column bioleaching of a low grade nickel bearing Sulfide Ore containing high magnesium as olivine chlorite and antigorite
Hydrometallurgy, 2009Co-Authors: Yansheng Zhang, Jun Wang, Shijie Zhen, Zhongqiang Yan, Maurice Campbell, Wenqing QinAbstract:Abstract This work investigates the bioleaching of Jinchuan low grade nickel-bearing Sulfide Ore containing rather high levels of olivine, chlorite and antigorite (MgO 30–35%) present in the main gangue minerals using a mixed mesophiles which are composed of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. It aims to test the technical feasibility to recover valuable metals from Jinchuan low-grade nickel-bearing Sulfide Ore by bioleaching process. The tolerance of the mixed bacteria to Mg 2+ could be improved markedly from 10 g/L to 25 g/L after nearly 2 years adaptation. A nickel recovery of 91% and a cobalt recovery of 81% were achieved in 312 days column leaching process including 60 days acid pre-leaching stage and 252 days bioleaching stage.
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simulated small scale pilot heap leaching of low grade copper Sulfide Ore with selective extraction of copper
Transactions of Nonferrous Metals Society of China, 2008Co-Authors: Wenqing Qin, Yansheng Zhang, L I Weizhong, Jun WangAbstract:Abstract The bioleaching of low-grade copper Sulfide Ore and the selective extraction of copper were investigated. Lix984 dissolved in kerosene was used as extractant. The results show that it is possible to selectively leach copper from the Ores by heap leaching. The copper concentration of leaching liquor after 250 d is 2.17 g/L, and the copper concentration is 0.27 g/L after solvent extraction. The leach liquor was subjected to solvent extraction, scrubbing and selective stripping for the enrichment of copper and the removal of impurities. The pregnant copper sulfate solution produced from the stripping cycle is suitable for copper electro-winning.
Yansheng Zhang - One of the best experts on this subject based on the ideXlab platform.
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bioleaching of a low grade nickel copper cobalt Sulfide Ore
Hydrometallurgy, 2011Co-Authors: Congren Yang, Yansheng Zhang, Jun Wang, Wenqing Qin, Shaoshi Lai, Fen Jiao, Liuyi Ren, Tian Zhuang, Ziyong ChangAbstract:Abstract The bioleaching behavior of copper and nickel from a low-grade nickel, copper, and cobalt-bearing Sulfide Ore was investigated. A recovery of 94% Ni, 62% Co and 70% Cu was achieved in 68 days of flask leaching including 18 days of acid pre-leaching and 50 days of bioleaching. However, a recovery of 46% Ni, 39% Co and 13% Cu was achieved in 139 days of column leaching including 19 days of acid pre-leaching and 120 days of bioleaching which indicates that nickel and cobalt have the same leaching behavior. Potassium, sodium and iron(III) ions in the leach solution formed jarosite within the Ore bed with some nickel and copper ions incorporated into the jarosite precipitates thereby diminishing the overall metal recovery. Magnesium was preferentially leached by acid from the gangue minerals leaving a magnesium depleted silicate skeleton, but discrepancies in the residue analysis indicate that magnesium re-deposits into the silicate skeleton during bioleaching.
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heap bioleaching of a low grade nickel bearing Sulfide Ore containing high levels of magnesium as olivine chlorite and antigorite
Hydrometallurgy, 2009Co-Authors: Wenqing Qin, Jun Wang, Shijie Zhen, Zhongqiang Yan, Maurice Campbell, Kai Liu, Yansheng ZhangAbstract:Abstract This work investigates the heap bioleaching of a low-grade nickel Sulfide Ore containing rather high levels of olivine, chlorite and antigorite (MgO 30–35%) present in the main gangue minerals. A 500-ton heap bioleaching system was developed and the microorganisms used in the test were a mixture of mesophiles, Acidithiobacillus ferrooxidans ( DQ321745 ), Acidithiobacillus thiooxidans ( EF059760 ) and Leptospirillum ferrooxidans (DSM2391). The inoculum used was obtained from a three-stage progressive scale-up (from 25 L to 500 L and finally to 10 m 3 ) culture. Industrial grade concentrated sulfuric acid and acid wastewater (pH 0.0–0.3) produced from off-gas treating during the smelting process were also used during bioleaching. A nickel (84.6%) and cobalt (75.0%) extraction was achieved after 350 days of heap leaching, including 80 days of acid pre-leaching and 270 days of bioleaching. The economical feasibility model predicted that the process was feasible.
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column bioleaching of a low grade nickel bearing Sulfide Ore containing high magnesium as olivine chlorite and antigorite
Hydrometallurgy, 2009Co-Authors: Yansheng Zhang, Jun Wang, Shijie Zhen, Zhongqiang Yan, Maurice Campbell, Wenqing QinAbstract:Abstract This work investigates the bioleaching of Jinchuan low grade nickel-bearing Sulfide Ore containing rather high levels of olivine, chlorite and antigorite (MgO 30–35%) present in the main gangue minerals using a mixed mesophiles which are composed of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. It aims to test the technical feasibility to recover valuable metals from Jinchuan low-grade nickel-bearing Sulfide Ore by bioleaching process. The tolerance of the mixed bacteria to Mg 2+ could be improved markedly from 10 g/L to 25 g/L after nearly 2 years adaptation. A nickel recovery of 91% and a cobalt recovery of 81% were achieved in 312 days column leaching process including 60 days acid pre-leaching stage and 252 days bioleaching stage.
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simulated small scale pilot heap leaching of low grade copper Sulfide Ore with selective extraction of copper
Transactions of Nonferrous Metals Society of China, 2008Co-Authors: Wenqing Qin, Yansheng Zhang, L I Weizhong, Jun WangAbstract:Abstract The bioleaching of low-grade copper Sulfide Ore and the selective extraction of copper were investigated. Lix984 dissolved in kerosene was used as extractant. The results show that it is possible to selectively leach copper from the Ores by heap leaching. The copper concentration of leaching liquor after 250 d is 2.17 g/L, and the copper concentration is 0.27 g/L after solvent extraction. The leach liquor was subjected to solvent extraction, scrubbing and selective stripping for the enrichment of copper and the removal of impurities. The pregnant copper sulfate solution produced from the stripping cycle is suitable for copper electro-winning.
Shijie Zhen - One of the best experts on this subject based on the ideXlab platform.
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heap bioleaching of a low grade nickel bearing Sulfide Ore containing high levels of magnesium as olivine chlorite and antigorite
Hydrometallurgy, 2009Co-Authors: Wenqing Qin, Jun Wang, Shijie Zhen, Zhongqiang Yan, Maurice Campbell, Kai Liu, Yansheng ZhangAbstract:Abstract This work investigates the heap bioleaching of a low-grade nickel Sulfide Ore containing rather high levels of olivine, chlorite and antigorite (MgO 30–35%) present in the main gangue minerals. A 500-ton heap bioleaching system was developed and the microorganisms used in the test were a mixture of mesophiles, Acidithiobacillus ferrooxidans ( DQ321745 ), Acidithiobacillus thiooxidans ( EF059760 ) and Leptospirillum ferrooxidans (DSM2391). The inoculum used was obtained from a three-stage progressive scale-up (from 25 L to 500 L and finally to 10 m 3 ) culture. Industrial grade concentrated sulfuric acid and acid wastewater (pH 0.0–0.3) produced from off-gas treating during the smelting process were also used during bioleaching. A nickel (84.6%) and cobalt (75.0%) extraction was achieved after 350 days of heap leaching, including 80 days of acid pre-leaching and 270 days of bioleaching. The economical feasibility model predicted that the process was feasible.
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column bioleaching of a low grade nickel bearing Sulfide Ore containing high magnesium as olivine chlorite and antigorite
Hydrometallurgy, 2009Co-Authors: Yansheng Zhang, Jun Wang, Shijie Zhen, Zhongqiang Yan, Maurice Campbell, Wenqing QinAbstract:Abstract This work investigates the bioleaching of Jinchuan low grade nickel-bearing Sulfide Ore containing rather high levels of olivine, chlorite and antigorite (MgO 30–35%) present in the main gangue minerals using a mixed mesophiles which are composed of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. It aims to test the technical feasibility to recover valuable metals from Jinchuan low-grade nickel-bearing Sulfide Ore by bioleaching process. The tolerance of the mixed bacteria to Mg 2+ could be improved markedly from 10 g/L to 25 g/L after nearly 2 years adaptation. A nickel recovery of 91% and a cobalt recovery of 81% were achieved in 312 days column leaching process including 60 days acid pre-leaching stage and 252 days bioleaching stage.
Jun Wang - One of the best experts on this subject based on the ideXlab platform.
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bioleaching of a low grade nickel copper cobalt Sulfide Ore
Hydrometallurgy, 2011Co-Authors: Congren Yang, Yansheng Zhang, Jun Wang, Wenqing Qin, Shaoshi Lai, Fen Jiao, Liuyi Ren, Tian Zhuang, Ziyong ChangAbstract:Abstract The bioleaching behavior of copper and nickel from a low-grade nickel, copper, and cobalt-bearing Sulfide Ore was investigated. A recovery of 94% Ni, 62% Co and 70% Cu was achieved in 68 days of flask leaching including 18 days of acid pre-leaching and 50 days of bioleaching. However, a recovery of 46% Ni, 39% Co and 13% Cu was achieved in 139 days of column leaching including 19 days of acid pre-leaching and 120 days of bioleaching which indicates that nickel and cobalt have the same leaching behavior. Potassium, sodium and iron(III) ions in the leach solution formed jarosite within the Ore bed with some nickel and copper ions incorporated into the jarosite precipitates thereby diminishing the overall metal recovery. Magnesium was preferentially leached by acid from the gangue minerals leaving a magnesium depleted silicate skeleton, but discrepancies in the residue analysis indicate that magnesium re-deposits into the silicate skeleton during bioleaching.
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heap bioleaching of a low grade nickel bearing Sulfide Ore containing high levels of magnesium as olivine chlorite and antigorite
Hydrometallurgy, 2009Co-Authors: Wenqing Qin, Jun Wang, Shijie Zhen, Zhongqiang Yan, Maurice Campbell, Kai Liu, Yansheng ZhangAbstract:Abstract This work investigates the heap bioleaching of a low-grade nickel Sulfide Ore containing rather high levels of olivine, chlorite and antigorite (MgO 30–35%) present in the main gangue minerals. A 500-ton heap bioleaching system was developed and the microorganisms used in the test were a mixture of mesophiles, Acidithiobacillus ferrooxidans ( DQ321745 ), Acidithiobacillus thiooxidans ( EF059760 ) and Leptospirillum ferrooxidans (DSM2391). The inoculum used was obtained from a three-stage progressive scale-up (from 25 L to 500 L and finally to 10 m 3 ) culture. Industrial grade concentrated sulfuric acid and acid wastewater (pH 0.0–0.3) produced from off-gas treating during the smelting process were also used during bioleaching. A nickel (84.6%) and cobalt (75.0%) extraction was achieved after 350 days of heap leaching, including 80 days of acid pre-leaching and 270 days of bioleaching. The economical feasibility model predicted that the process was feasible.
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column bioleaching of a low grade nickel bearing Sulfide Ore containing high magnesium as olivine chlorite and antigorite
Hydrometallurgy, 2009Co-Authors: Yansheng Zhang, Jun Wang, Shijie Zhen, Zhongqiang Yan, Maurice Campbell, Wenqing QinAbstract:Abstract This work investigates the bioleaching of Jinchuan low grade nickel-bearing Sulfide Ore containing rather high levels of olivine, chlorite and antigorite (MgO 30–35%) present in the main gangue minerals using a mixed mesophiles which are composed of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. It aims to test the technical feasibility to recover valuable metals from Jinchuan low-grade nickel-bearing Sulfide Ore by bioleaching process. The tolerance of the mixed bacteria to Mg 2+ could be improved markedly from 10 g/L to 25 g/L after nearly 2 years adaptation. A nickel recovery of 91% and a cobalt recovery of 81% were achieved in 312 days column leaching process including 60 days acid pre-leaching stage and 252 days bioleaching stage.
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simulated small scale pilot heap leaching of low grade copper Sulfide Ore with selective extraction of copper
Transactions of Nonferrous Metals Society of China, 2008Co-Authors: Wenqing Qin, Yansheng Zhang, L I Weizhong, Jun WangAbstract:Abstract The bioleaching of low-grade copper Sulfide Ore and the selective extraction of copper were investigated. Lix984 dissolved in kerosene was used as extractant. The results show that it is possible to selectively leach copper from the Ores by heap leaching. The copper concentration of leaching liquor after 250 d is 2.17 g/L, and the copper concentration is 0.27 g/L after solvent extraction. The leach liquor was subjected to solvent extraction, scrubbing and selective stripping for the enrichment of copper and the removal of impurities. The pregnant copper sulfate solution produced from the stripping cycle is suitable for copper electro-winning.
Hailin Yang - One of the best experts on this subject based on the ideXlab platform.
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enhanced contact mechanism for interaction of extracellular polymeric substances with low grade copper bearing Sulfide Ore in bioleaching by moderately thermophilic acidithiobacillus caldus
Journal of Environmental Management, 2019Co-Authors: Zhuangzhuang Huang, Shoushuai Feng, Yanjun Tong, Hailin YangAbstract:In order to enhance the "contact mechanism" governing the interaction of extracellular polymeric substances (EPS) with low-grade copper-bearing Sulfide Ore for the bioleaching of copper, moderately thermophilic Acidithiobacillus caldus was subjected to exogenous intervention with iron and sulfur. The enhancement of the contact mechanism was systematically investigated by evaluating the attached cells/EPS dynamics, intracellular adenosine triphosphate (ATP), cell functional groups, gene transcriptional level, and Ore characteristics. Confocal laser scanning microscopy (CLSM) revealed that exogenous intervention with iron and sulfur led to the production of a denser EPS layer and faster adsorption of the attached cells to the Ore based on differential fluOrescence staining, which indicated enhancement of the "contact mechanism". The increased intracellular ATP content of the attached cells in the exogenous substrate system provided the required energy for the adsorption processes associated with the "contact mechanism". Fourier-transform infrared spectroscopic (FTIR) analysis of the attached cells and the Ore showed a dramatic shift of the NH and COS peaks (associated with EPS formation), whereas the FTIR peaks of SO and SO42- associated with sulfur metabolism were also significantly influenced. MOreover, reverse transcription polymerase chain reaction (RT-PCR) analysis revealed that the expression of genes related to cellular energy metabolism (nuoB, nuoC, atpE, atpF), sulfur metabolism (sor, sqr, sdo, soxA), biofilm formation (pgaA, pgaB), and cell colonization (acfA, acfB, acfC, acfD) was up-regulated after exogenous intervention, verifying enhancement of the "contact mechanism" at the transcriptional level. In addition, scanning electron microscopy (SEM) indicated mOre obvious adsorption traces on the Ore surface. X-ray diffraction (XRD) indicated the presence of mOre complex derivatives, such as Fe3(SO4)4, FeSO4, Fe2(SO4)3, and Cu2S, which is suggestive of mOre active iron/sulfur metabolism with addition of the exogenous iron and sulfur. Overall, a model for bioleaching of low-grade copper-bearing Sulfide Ore by moderately thermophilic A. caldus was constructed. The results of this investigation should provide a guide for similar industrial bioleaching processes.
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Specific mechanism of Acidithiobacillus caldus extracellular polymeric substances in the bioleaching of copper-bearing Sulfide Ore
2019Co-Authors: Shoushuai Feng, Zhuangzhuang Huang, Yanjun Tong, Hailin YangAbstract:This study aimed to reveal the specific mechanism of extracellular polymeric substances (EPS) in the bioleaching of copper-bearing Sulfide Ore by moderately thermophilic bacterium Acidithiobacillus caldus. The bioleaching performance of blank control (BC), planktonic cell deficient (PD), attached cell deficient (AD), and EPS deficient (ED) systems were compared, to investigate the specific functions of “non-contact” and “contact” (including direct contact and, EPS-mediated contact) mechanisms. The detailed mechanics of bioleaching were studied using μx of cell growth, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The μx of cell growth demonstrated that EPS favors planktonic and attached cell growth. SEM observation revealed that intensive micro-pOres on slag benefitted from the “EPS-mediated contact” mechanism. XRD identification indicated that additional chemical derivatives were produced via “EPS-mediated contact” mechanism, because of the active iron/sulfur metabolism. FTIR analysis revealed that the absorption peaks of C-O-S, sulfate, and S = O, which are closely associated with sulfur metabolism, have significant influences of EPS secretion. Taken together, the “EPS-mediated contact” mechanism contributed to almost half of the “contact” mechanism efficiency and a quarter of the total bioleaching efficiency. The proposed specific mechanism of EPS can deepen our understanding of similar bioleaching processes.
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Overview of the specific function of the “EPS-mediated contact” mechanism in the bioleaching of copper-bearing Sulfide Ore by the moderately thermophilic Acidithiobacillus caldus.
2019Co-Authors: Shoushuai Feng, Zhuangzhuang Huang, Yanjun Tong, Hailin YangAbstract:Overview of the specific function of the “EPS-mediated contact” mechanism in the bioleaching of copper-bearing Sulfide Ore by the moderately thermophilic Acidithiobacillus caldus.
