APPLIED SURFACE SCIENCE
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2021
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IF 6.707
Shangyong Lin,Chengwen Wang,Runqing Liu,Wei Sun,Gaogui Jing
Researchers in most of the published works paid a great attention in the effects of pH on the flotation behavior of minerals, where most of which ignored the influences of pH on the surface properties. Herein, the detailed surface analyses of several typical sulfide minerals, namely, molybdenite, bismuthinite, and pyrite, were conducted to identify the effect of pH on the mineral surface property. As observed, all these minerals exhibited excellent hydrophobicity under highly acid conditions. The surface chemical composition of molybdenite and bismuthinite remained relatively steady as pH increased, but the decrease in surface hydrophobicity of bismuthinite was more serious than that of molybdenite under the alkaline conditions. Pyrite was more affected by the pH value. At pH below 4.0, FeS 2 was the dominate species at pyrite surface. With the increase in alkalinity , the pyrite was gradually oxidized and the surface became hydrophilic. As the pH further increased to12.0, the hydrophobicity of pyrite almost vanished due to the deposition of hydrophilic oxidation products (e.g., Fe 2 (SO 4 ) 3 , Fe(OH) 3 , and FeOOH) on its surface. The differences in the surface characteristics of molybdenite, bismuthinite, and pyrite at different pH values can be used to design the flotation process for separation of these sulfide minerals.
研究领域:
矿物学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2023
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IF 8.4
Wei Jin,Shenghai Yang,Chaobo Tang,Yun Li,Cong Chang,Yongming Chen
Traditional bismuthinite concentrate precipitation smelting has problems of low recovery of valuable metals (e.g., Bi, Cu, Mo, and Ag), high fuel consumption, and high cost of SO2 flue gas treatment. Therefore, in this study, an eco-friendly alkaline smelting process was proposed to extract metallic bismuth and recover valuable metals. The phase equilibrium composition of the Bi2S3-Na2CO3-C system was revealed by thermodynamic simulations at different temperatures and reductant contents. Based on reaction product characterizations and thermodynamic simulations, the following reaction mechanism and suitable bismuth extraction path were confirmed: Bi2S3 first reacted with Na2CO3 to form Bi2O3 and Na2S, and the intermediate (Bi2O3) was then reduced to metallic Bi by both C and CO. Under optimized conditions (Wbismuthinite/WNa2CO3/Wcoke = 200:300:20, 900 °C, 150 min), up to 96.56% Bi, 75.07% Pb, and 85.11% Ag were enriched in crude bismuth, respectively, while 93.57% Cu, 70.23% Fe, 96.63% Mo, and 94.34% W entered the salt slag. More than 99.9% W and Mo were recovered as Na2WO4 and Na2MoO4, respectively, from the salt slag by water leaching. In the leaching residue, chalcopyrite, pyrite, and elemental sulfur could be recovered by flotation.
研究领域:
冶金学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
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2023
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IF 4.8
Shangyong Lin,Hongliang Zhang,Xiangsong Meng,Ruolin Wang,Wei Sun,Haisheng Han,Chenyang Zhang
Molybdenite and bismuthinite are valuable components arising from Mo–Bi sulfide ore, and their recoveries are considerably limited by separation efficiency. Herein, calcium hypochlorite (Ca(ClO) 2 ) was first introduced as bismuth depressant for efficient separation of molybdenite and bismuthinite, and its depression mechanisms were investigated through a series of analytical techniques supplemented with solution chemistry and thermodynamic calculations. Flotation results showed that Ca(ClO) 2 had a stronger depressing ability than conventional depressant sodium sulfide and exhibited superior selectivity for bismuthinite against molybdenite. At pH around 8.0, the high-selective separation of Mo–Bi bulk concentrate was realized, where more than 96% of molybdenite was recovered and over 98% of bismuthinite was depressed. Solution chemistry and thermodynamic analysis indicated that the bismuthinite surface was preferentially oxidized by Ca(ClO) 2 to SO2- 4 and Bi 3+ . The former dissolved into solution and existed as stable ions, whereas the Bi 3+ further interacted with Cl − and was hydrolyzed as BiOCl precipitates. Surface analysis demonstrated that the deposition of BiOCl on the bismuthinite surface not only made its surface rougher but also enhanced its surface hydrophilicity. In comparison, the surface of molybdenite was slightly oxidized and it remained hydrophobic as confirmed from scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and contact angle results. The difference in surface characteristics resulted in the selective adsorption of collector on the surface of molybdenite rather than that of bismuthinite, thus improving the floatability of molybdenite and drastically deteriorating the floatability of bismuthinite. This work suggests that Ca(ClO) 2 could be a promising depressant for bismuthinite in the flotation separation of Mo–Bi sulfide ore.
研究领域:
矿物加工工程
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材料科学与工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）