Evaluation of flotation collectors for copper sulfides and pyrite, I. Common sulfhydryl collectors

1987 ◽  
Vol 21 (1-2) ◽  
pp. 105-127 ◽  
Author(s):  
P.K. Ackerman ◽  
G.H. Harris ◽  
R.R. Klimpel ◽  
F.F. Aplan
Catalysts ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 899
Author(s):  
Murendeni P. Ravele ◽  
Opeyemi A. Oyewo ◽  
Damian C. Onwudiwe

Pure-phase Cu2−xS (x = 1, 0.2) nanoparticles have been synthesized by the thermal decomposition of copper(II) dithiocarbamate as a single-source precursor in oleylamine as a capping agent. The compositions of the Cu2−xS nanocrystals varied from CuS (covellite) through the mixture of phases (CuS and Cu7.2S4) to Cu9S5 (digenite) by simply varying the temperature of synthesis. The crystallinity and morphology of the copper sulfides were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), which showed pure phases at low (120 °C) and high (220 °C) temperatures and a mixture of phases at intermediate temperatures (150 and 180 °C). Covellite was of a spherical morphology, while digenite was rod shaped. The optical properties of these nanocrystals were characterized by UV−vis–NIR and photoluminescence spectroscopies. Both samples had very similar absorption spectra but distinguishable fluorescence properties and exhibited a blue shift in their band gap energies compared to bulk Cu2−xS. The pure phases were used as catalysts for the photocatalytic degradation of tetracycline (TC) under visible-light irradiation. The results demonstrated that the photocatalytic activity of the digenite phase exhibited higher catalytic degradation of 98.5% compared to the covellite phase, which showed 88% degradation within the 120 min reaction time using 80 mg of the catalysts. The higher degradation efficiency achieved with the digenite phase was attributed to its higher absorption of the visible light compared to covellite.


2006 ◽  
Vol 295 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Zhaodong Nan ◽  
Xue-Ying Wang ◽  
Zongbin Zhao

Geophysics ◽  
1981 ◽  
Vol 46 (9) ◽  
pp. 1278-1290 ◽  
Author(s):  
L. E. Reed

In June 1974, a diamond drill operated for Selco Mining Corp. intersected zinc‐copper sulfides in Brouillan Township in northwestern Québec. To date, two bodies have been outlined. These bodies were discovered during a ground follow‐up of a Mark VI Input® electromagnetic (EM) survey. The Input survey covered an area selected on the basis of regional geology and local outcrops of acid volcanic rocks. Conductors were identified that appeared to be associated with potentially favorable geology. They were selected for ground follow‐up. One was the discovery zone. The airborne responses over the zone were less encouraging than those often observed over highly conductive massive sulfides. The low apparent conductivity‐thickness (5 mhos) was suggestive of conductive overburden. However, the character of the profiles suggested a bedrock source. Ground geophysical confirmation identified a drill target. Subsequent to the discovery, more intensive geophysical surveys, both ground and airborne, were carried out. The best EM response suggested a confined source within a much larger mineralized halo. Weaker ground EM response from the halo correlated with the early channel response of the Input system. An airborne EM survey conducted in 1958 over the same area identified both conductive zones. However, they were not followed up. Only with later advances in exploration philosophy, geologic appreciation, and instrumentation were the conductive zones recognized as viable exploration targets.


2017 ◽  
Vol 123 ◽  
pp. 39-45 ◽  
Author(s):  
Lu Jia ◽  
Huiming Ji ◽  
Junyun Lai ◽  
Jian Wang ◽  
Huayu Chen ◽  
...  

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