The Study of Copper Leaching from Conichalcite and Chalcopyrite Using Alternative Lixiviants

Author(s):  
Junmo Ahn ◽  
Isabel F. Barton ◽  
Doyun Shin ◽  
Jaeheon Lee
Keyword(s):  
Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 230
Author(s):  
Pengcheng Ma ◽  
Hongying Yang ◽  
Zuochun Luan ◽  
Qifei Sun ◽  
Auwalu Ali ◽  
...  

Bacteria–mineral contact and noncontact leaching models coexist in the bioleaching process. In the present paper, dialysis bags were used to study the bioleaching process by separating the bacteria from the mineral, and the reasons for chalcopyrite surface passivation were discussed. The results show that the copper leaching efficiency of the bacteria–mineral contact model was higher than that of the bacteria–mineral noncontact model. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) were used to discover that the leaching process led to the formation of a sulfur film to inhibit the diffusion of reactive ions. In addition, the deposited jarosite on chalcopyrite surface was crystallized by the hydrolysis of the excess Fe3+ ions. The depositions passivated the chalcopyrite leaching process. The crystallized jarosite in the bacteria EPS layer belonged to bacteria–mineral contact leaching system, while that in the sulfur films belonged to the bacteria–mineral noncontact system.


2005 ◽  
Vol 23 (3) ◽  
pp. 255-266 ◽  
Author(s):  
J. O'Brien ◽  
T. Curtin ◽  
T.F. O'Dwyer

Zeolite beta, a large-pore zeolite, was investigated in this study with a view to examining it as a potential adsorbent for the removal of aniline from aqueous solutions. Two different metal-loaded zeolites were prepared by exchanging H-beta zeolite (SiO2/Al2O3 = 75:1) with copper. The influence of exchanged copper on the uptake level was assessed. The effect of varying the silica-to-alumina ratio of the H-beta zeolite on the aniline uptake level was also examined, using three different H-beta zeolites with ratios of 25:1, 75:1 and 150:1 as adsorbents. The sorption experiments indicated an uptake level of ca. 110–120 mg/g for each zeolite and this level was also adsorbed by the copper-modified H-beta zeolites (SiO2/Al2O3 = 75:1). In all cases, the adsorption process followed the Langmuir model for adsorption and the level of aniline adsorbed was largely unaffected by a change in temperature or the presence of extra framework copper. The stability of the exchanged copper on these zeolites was then examined by measuring the quantity of copper leached from each zeolite into solution as a function of pH. Minimum copper leaching was observed in the pH range 5–11. This provided a stable pH working range for the adsorbent materials.


Holzforschung ◽  
2014 ◽  
Vol 68 (4) ◽  
pp. 477-486 ◽  
Author(s):  
Myung Jae Lee ◽  
Sedric Pankras ◽  
Paul Cooper

Abstract Canadian refractory wood species treated with micronized copper (MCu) wood preservative become mottled and streaky in appearance. To overcome this issue, the MCu system was modified by adding small amounts of monoethanolamine (Mea). The modified systems were evaluated to clarify the role of Mea in terms of leaching, corrosion, and mold resistance of MCu systems. The mottled and streaky surface on treated spruce was prevented at Mea/Cu molar ratios between 0.7 and 1.5. Copper leaching remained modest and was only slightly higher than that of MCu alone up to a Mea/Cu molar ratio of 1.2. However, adding even a small amount of Mea to the MCu formulation increased fastener corrosion compared with MCu. Protonated Mea increased as more Mea was added and was identified as the main corrosion-causing electrolyte in the system.


Minerals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 79 ◽  
Author(s):  
Linlin Tong ◽  
Qianfei Zhao ◽  
Ali Kamali ◽  
Wolfgang Sand ◽  
Hongying Yang

The efficient extraction of copper as a valuable metal from waste printed circuit boards (WPCBs) is currently attracting growing interest. Here, we systematically investigated the impact of bacteria on the efficiency of copper leaching from WPCBs, and evaluated the effect of graphite on bioleaching performance. The HQ0211 bacteria culture containing Acidithiobacillus ferrooxidans, Ferroplasma acidiphilum, and Leptospirillum ferriphilum enhanced Cu-leaching performance in either ferric sulfate and sulfuric acid leaching, so a final leaching of up to 76.2% was recorded after 5 days. With the addition of graphite, the percentage of copper leaching could be increased to 80.5%. Single-factor experiments confirmed the compatibility of graphite with the HQ0211 culture, and identified the optimal pulp density of WPCBs, the initial pH, and the graphite content to be 2% (w/v), 1.6, and 2.5 g/L, respectively.


2010 ◽  
Vol 69 (2) ◽  
pp. 263-269 ◽  
Author(s):  
Andreas Treu ◽  
Erik Larnøy ◽  
Holger Militz

2009 ◽  
Vol 71-73 ◽  
pp. 409-412
Author(s):  
Wen Qing Qin ◽  
Yan Sheng Zhang ◽  
Shi Jie Zhen ◽  
Jun Wang ◽  
Jian Wen Zhang ◽  
...  

The effects of several variables on the column bioleaching of copper sulphide ore have been investigated. The copper ore contained chalcopyrite as the main sulfide minerals and bornite and chalcocite as the minor minerals. The experiment was carried out using bench-scale column leach reactors designed in Key Lab of Biometallurgy of Ministry of Education, which were inoculated with the pure mesophile bacteria (Acidithiobacillus ferrooxidans) and thermophile bacteria (Sulfobacillus), respectively, and the mixed bacteria which contain both iron- and sulfur-oxidizing bacteria. The results show that the mixed cultures were more efficient than the pure cultures alone and the maximum copper recovery 53.64% was achieved using the mixed cultures after 85 days. The leaching rate of chalcopyrite tended to increase with the increased dissolved ferric iron concentration. The effect of particle size on the rate of the copper leaching was also investigated, and it was shown that the copper bioleaching rate decreases as the amount of fines increase, which limits the permeability, thus decreases leaching rate. Jarosite and elemental sulphur formed in the column were characterized by the X-ray and EDS.


Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1213
Author(s):  
Rod Stirling ◽  
Gabrielle Boivin ◽  
Adnan Uzunovic ◽  
Stacey Kus ◽  
John N. R. Ruddick

Wood is vulnerable to significant color changes when used in exterior applications. Some copper-based wood preservatives use colorants to minimize this color change. This paper examines the ability of a peroxide post-treatment to turn wood impregnated with micronized basic copper carbonate (CuCO3·Cu(OH)2) (MBCC) a stable brown color. MBCC-treated wood, with and without peroxide post-treatment, along with associated controls were evaluated for color change, erosion and black-stain fungal resistance after exposure to artificial photo-degradation. The impact of the peroxide treatment on copper leaching was assessed in a laboratory experiment, and the impact on copper reactivity was assessed by electron parametric resonance (EPR) spectroscopy. Peroxide post-treatment of wood pressure impregnated with MBCC was shown to reduce color change by more than 50% compared to controls. Erosion due to photo-degradation and colonization by black-stain fungi were lower in samples treated with MBCC than in untreated controls and were relatively unaffected by peroxide post-treatment. The peroxide post-treatment was associated with increased amounts of mobile copper. This led to increased susceptibility to leaching and to a more than 60% increase in the amount of copper than had reacted with the wood.


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