PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2024
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IF 6.9
Linquan Dai,Bo Feng,Mengyan Tang,Yuangan Chen
It is challenging to separate between molybdenite and chalcopyrite due to their comparable hydrophobic characteristics. Inorganic depressants were previously used to separate two minerals, but the results were unsatisfactory and polluted the environment. In this study, the molybdenite and chalcopyrite were separated using a highly effective and ecologically safe depressant, 2,4-Diamino-6-hydroxypyrimidine (DAHP). According to the single mineral experiment, chalcopyrite is totally depressed while molybdenite has superior floatability. The efficacy of DAHP as the depressant was validated by further artificially mixed mineral flotation experiments, indicating the possibility of separating chalcopyrite and molybdenite. The adsorption capacity experiment results showed that the adsorption capacity of DAHP on the surface of chalcopyrite was greater than that on the surface of molybdenite. Zeta potential experiment results show that DAHP is adsorbed on the surface of chalcopyrite and molybdenite through static electrostatic interactions . X-ray photoelectron spectroscopy (XPS) experiment results show that DAHP is mainly adsorbed on chalcopyrite surface through –NH 3 + group, which hinders the adsorption of kerosene. The electrostatic contact between DAHP and molybdenite has the least effect on kerosene adsorption. This study shows that DAHP has the potential to separate chalcopyrite and molybdenite as an efficient and environmentally friendly depressant.
研究领域:
矿物加工工程
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2024
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IF 5.3
Yong Zeng,Yingdi Dong,Xiongxing Zhang,Zhongbao Hua,Xiqing Wu,Wei Sun,Haisheng Han,Li Wang,Honghu Tang
In the flotation separation of Mo-Pb bulk concentrate and the purification process of Pb-containing molybdenite concentrate, depressants are typically added to depress galena or molybdenite, aiming to obtain high-quality flotation products. Previous studies have focused on the depression of galena. In this study, gallic acid (GA) was utilized as a molybdenite depressant during Mo-Pb flotation separation. Single mineral flotation experiments showed that pH notably influenced galena and molybdenite flotation with GA, particularly at pH 10, displaying the most substantial recovery difference. Mixed mineral flotation experiments revealed GA’s selective depression on molybdenite. At the optimal dosage of GA, the Mo recovery was reduced by 76.62 percentage points, while the Pb recovery remained unaffected. The depression and separation mechanisms of GA were investigated using contact angle, infrared spectroscopy, Zeta potential, inductively coupled plasma optical emission spectrometer (ICP-OES), X-ray photoelectron spectroscopy (XPS) analysis, first-principles calculations analysis, and interface interaction free energy calculations. The results indicate that GA treatment significantly reduces the hydrophobicity of molybdenite surfaces; however, it slightly enhances the hydrophobicity of galena surfaces. At pH 10, the primary species in GA solution is HGA 3- . It adsorbs on PbO species of the galena surface as Pb-GA complexes and tends to detach from the surface at high adsorption capacity, resulting in galena not being depressed by GA. Differently, GA adsorbs on the molybdenite surface through hydrophobic attraction force, rendering it hydrophilic. Additionally, after treatment with potassium butyl xanthate (PBX), the hydrophobicity of GA-treated galena is significantly enhanced, while the hydrophobicity of GA-treated molybdenite is not restored. This is because PBX can adsorb stably on GA-treated galena, but its adsorption on GA-treated molybdenite is hindered by the pre-adsorbed GA.
研究领域:
矿物加工工程
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化学工程
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材料科学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Jie Wu,Siyi Li,Bingqiao Yang,Hui Shao,Shaoxian Song,Feifei Jia,Mildred Quintana
Improving the flotation efficiency of molybdenite fines is a challenging job worldwide. In this work, sodium 2-Mercaptobenzothiazole (MBT) was explored as a potential collector to recover molybdenite fines efficiently. The flotation behaviors were estimated by micro-flotation tests. The interaction mechanism was probed by contact angle, Scanning Electron Microscope and Energy Dispersive Spectrometer (SEM-EDS), Zeta potential, X-ray Photoelectron Spectroscopy (XPS), adsorption capacity and density functional theory (DFT) calculation. The flotation tests revealed that MBT effectively improved the floatability of molybdenite fines at pH of 2 – 12, which exhibited stronger collecting ability than kerosene in the flotation of molybdenite fines. Contact angle, Zeta potential and adsorption capacity results revealed MBT enhanced the hydrophobicity of molybdenite surfaces, thus improving the flotation of molybdenite. SEM-EDS and adsorption energy results suggested MBT was more favorable to adsorb on edges (-268.87 kJ/mol) than that on faces (-40.09 kJ/mol). XPS and DFT calculation further demonstrated that N 2p and S 3p orbitals within MBT complexed with Mo 4d orbitals of two Mo atoms on edges to form a bidentate model. MBT had a good prospect of substituting kerosene in the flotation of molybdenite fines.
研究领域:
矿物加工
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化学工程
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材料科学
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产品关联
DOI
高影响因子
MINERALS ENGINEERING
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2021
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IF 4.765
Xun Wang,Bing Zhao,Jie Liu,Yimin Zhu,Yuexin Han
In the present study, dithiouracil was employed as the chalcopyrite depressant to selectively change the properties of chalcopyrite surface and separate molybdenite from chalcopyrite. Micro-flotation experiments were carried out to investigate the separation efficiency of dithiouracil on the flotation separation of molybdenite from chalcopyrite. Furthermore, the depression mechanism of dithiouracil was explored at molecular level via zeta potential measurements, fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) analyses. The results showed that dithiouracil strongly depressed chalcopyrite flotation while had less impact on molybdenite flotation, and a satisfactory separation result was acquired by using dithiouracil. Zeta potential measurements and FTIR analyses illustrated that dithiouracil was chemisorbed on chalcopyrite surface. Furthermore, XPS and ToF-SIMS measurements confirmed that dithiouracil could react with Cu atoms on chalcopyrite surface through forming a four membered chelating ring. This paper indicated that dithiouracil can be employed as a high-performance chalcopyrite depressant for the Cu-Mo flotation separation.
研究领域:
矿物加工工程
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表面化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2026
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IF 5.1
Wei Chen,Yuhan Long,Qiqiao Liu,Yuhang Che,Ying Wang,Qing Sun,Hao Chen
Separating talc from molybdenite is notoriously difficult in practice, mainly because both minerals share a strong natural hydrophobicity and readily undergo hetero-coagulation. To overcome the shortcomings of conventional depressants, such as poor selectivity and molecular entanglement, this study developed a novel heterocyclic depressant, (Z)-5,6,7,8-tetrahydro-1,2,3-oxy-sulfur-azacyclic octanedione (TOD). TOD combines a carbon chain backbone with sulfonate groups, which allows it to selectively depress talc through a dual mechanism: hydrophobic engagement and specific chelation of magnesium ions. Density functional theory (DFT) and molecular dynamics simulation (MDS) results reveal that TOD adsorbs on the basal plane of talc via hydrophobic attraction and concurrently chelates Mg sites along the edges. In situ optical microscopy and Extended Derjaguin-Landau-Verwey-Overbeek (EDLVO) theory further support that TOD disrupts hydrophobic attraction between molybdenite and talc particles, markedly reducing their tendency to adhere. Contact angle, zeta potential, Fourier transform infrared spectrometer (FTIR), and adsorption measurements consistently demonstrate that TOD adsorbs preferentially onto the talc basal plane. This adsorption significantly reduces talc’s hydrophobicity and drops its surface potential below –35 mV, shifting the talc–molybdenite system from aggregation toward dispersion. In micro-flotation tests with sodium isobutyl xanthate as collector, TOD created a 39.26% recovery gap between talc and molybdenite, demonstrating strong selective depression and promising potential for industrial application.
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Longyu Zhang,Weijun Peng,Wei Wang,Yijun Cao,Mengyao Qi,Yukun Huang
Electrochemical oxidation (EO) has received widespread attention as a green and non-polluting oxidation treatment. In this paper, we used EO to pretreat pyrite and molybdenite, and then flotation was adopted to separate them. The flotation behavior of the pyrite and molybdenite was studied by micro-flotation tests, and the mechanism for the flotation separation of them was explored via XPS, zeta potential, water contact angle and electrochemistry, etc. The flotation results showed that the floatability of pyrite declined sharply after EO treatment, while that of molybdenite was not affected. In the flotation experiments of artificially mixed ores with various mass ratios, the recoveries of pyrite and molybdenite in the concentrates varied considerably. The mechanism analysis showed that pyrite had a drastic decrease in floatability due to the generation of hydrophilic products of Fe(OH) 3 , FeOOH and Fe 2 (SO 4 ) 3 covered on its surface in the EO process. Additionally, the oxidation products further hindered the adsorption of the collector of sodium butylxanthate on the pyrite surface. However, the generated MoO 4 2- and SO 4 2- of molybdenite were rapidly dissolved in the pulp during the EO process, allowing its original surface and floatability to be maintained. Therefore, EO pretreatment could generate a great variance in surface properties of pyrite and molybdenite, resulting in an efficient separation of pyrite and molybdenite via subsequent flotation. The work provided a green and environmentally-friendly alternative method to achieve efficient separation of pyrite and molybdenite.
研究领域:
矿物加工工程
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环境科学
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材料化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Yanchun Huang,Leiduo Lai,Weifang Huang,Hongyu Zhou,Jun Li,Chao Liu,Bo Lai,Naiwen Li
In this study, natural molybdenite (MoS 2 ) was applied to activate peroxymonosulfate (PMS) for the removal of atrazine (ATZ) and its degradation mechanism was investigated. Molybdenite exhibits superior catalytic performance. The best condition for atrazine degradation efficiency (>99%) was obtained with molybdenite concentration of 0.4 g/L, PMS concentration of 0.1 mM, and ATZ concentration of 12 μM within 10 min under experimental conditions. Electron paramagnetic resonance (EPR) test and chemical probe test further proved that HO • and SO 4 •− played important roles in the molybdenite/PMS system, and SO 4 •− was dominant. Meanwhile, Electron paramagnetic resonance (EPR) and X-ray photoelectron spectroscopy (XPS) tests showed that sulfur vacancies and edge sulfur played important roles in the system. Edge sulfur was conducive to Mo 4+ exposure, while sulfur vacancy facilitated electron transfer and reduced Mo 6+ back to Mo 4+ . Combined with DFT calculation, the role of sulfur in the degradation process was verified. Besides, five ATZ degradation pathways were proposed. Finally, the degradation ability of the molybdenite/PMS system for different pollutants and in actual water bodies was also explored. This work provided ideas for exploring the degradation of organic contaminants by natural minerals.
研究领域:
环境科学
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化学
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产品关联
DOI
PubMed
高影响因子
POWDER TECHNOLOGY
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2019
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IF 3.413
Hu Sun,Guanghui Li,Junjie Yu,Jun Luo,Mingjun Rao,Zhiwei Peng,Tao Jiang
The existing methods for MoO 3 production from high-grade molybdenite concentrates normally suffer from the inefficiency of oxidation and complexity of the overall process. In this work, a novel method for MoO 3 production from alumina-silica-added molybdenite concentrate pellets by simultaneous oxidizing-volatilizing was proposed, validated and compared with other methods. Molybdenite concentrate mixed with additives was fabricated into spherical balls and roasted in air. Molybdenum disulfide was rapidly oxidized, volatilized and thus separated from pellets, wherein additives were sintered to be mullite as porous framework to keep the strength of single pellet, and in turn to support the stacked pellets. With mass ratio of additives to ore 1:2, ratios of S removal and Mo recovery from pellets reached over 99.9% and 97.2% respectively at 1050 °C within 20 min, and the condensed material was identified to be valuable MoO 3 with purity over 99.9%. The excellent performance of MoO 3 separation was attributed to the construction of firm pellet layers and favorable diffusion conditions inside pellets.
研究领域:
冶金学
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材料加工
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无机化学
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提取冶金
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
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2026
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IF 6
Yudi Yan,Siyi Li,Bingqiao Yang,Weijun Peng,Kholov Kholmahmad Isroilovich,Safarov Sayfidin Shahobidinovich,Feifei Jia
The composite collector surpassed single collector on molybdenite fines flotation. • PEG600MO chemisorbed on edge and promoted the adsorption of emulsified kerosene. • PEG600MO and emulsified kerosene co-adsorbed on face to enhance its hydrophobicity. • The synchronous interfacial regulation was realized using the composite collector. The efficient recovery of fine molybdenite particles remains a significant challenge in mineral processing, largely attributed to the remarkably enhanced hydrophilicity as particle size reduces. Conventional non-polar collectors show limited effectiveness in floating such fine fractions. In the present study, a novel composite collector made of poly ethylene glycol 600 monooleate (PEG600MO) and emulsified kerosene was designed to boost the flotation of molybdenite particles smaller than 20 μm, relying on the synchronous interfacial modulation of both faces and edges. Flotation test results indicated that this composite collector outperformed individual collectors, significantly improving the flotation efficiency of fine molybdenite particles. The results of contact angle, electrokinetic measurements, Fourier transform infrared spectroscopy (FTIR), adsorption capacity and electrochemical tests demonstrated that PEG600MO was inclined to adsorb on molybdenite edges, promoting emulsified kerosene to adsorb on edges through hydrophobic interactions, meanwhile PEG600MO and emulsified kerosene co-adsorbed on faces physically. The differential adsorption of various components significantly improved the hydrophobicity of both faces and edges. X-ray photoelectron spectroscopy (XPS) results confirmed that the hydroxyl groups in PEG600MO underwent chemical interactions with Mo atoms on molybdenite. This work developed an effective composite collector and offered a new perspective on the design of flotation reagents for the efficient recovery of fine molybdenite particles.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2025
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IF 5.2
Mengyao Qi,Pengyu Wang,Xinyu Li,Weijun Peng,Yehao Huang,Wei Wang,Yijun Cao,Longyu Zhang,Yukun Huang
Flotation, an efficient and widely used industrial process, is a cornerstone of mineral processing. Reagents are critical to flotation efficiency, with depressants playing a decisive role in the separation of sulfide ore with similar flotability. This study involved the design and synthesis of a small organic molecule. Highly active aromatic organic acids were selected as reactants, and quantum chemical calculations were conducted to evaluate the stability of the synthesized products and their adsorption strength on the molybdenite surface. Infrared and nuclear magnetic resonance spectroscopy were employed to characterize the structure and purity of the compounds. The small molecular organic was used as a flotation depressant for molybdenite, and its ability to separate molybdenite from chalcopyrite was evaluated through a flotation experiment. This molecule achieved excellent flotation separation of molybdenite, offering a new approach for designing, developing, and applying innovative flotation reagents.
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2025
·
IF 5
Qiqiao Liu,Wei Chen,Ying Wang,Zihan Ye,Sheng Liu,Jiang Yu,Guangyi Liu
The molybdenite is a typical layered sulfide mineral with extremely high natural hydrophobicity and therefore it is extracted by flotation technology. However, molybdenite is usually depressed by the flotation regulator lime and needs activization. In this study, we introduced 10 kinds of N-heterocycles to systematically study the structure–activity relationship of the N-heterocyclic flotation activators for the lime inhibited molybdenite, mainly through flotation tests, surface detection and DFT calculation. The flotation results showed that the lime almost irreversibly depressed the molybdenite flotation when using kerosene as collector alone, and adding these N-heterocyclic reagents effectively helped molybdenite regain its high flotability. When lime was used as 120 mg/L and kerosene at 30 mg/L, the activator effect could be ranked as: 3MI ≈ 2Phl ≈ 5 MB ≈ 5MI ≈ TTA > IND ≈ BTA ≈ Bzlm ≈ 5PhTH > 2MZ, which was decided by the recovery increment. The surface detection indicated that the depression mechanism of the lime was mainly through the adsorption of the CaOH + , Ca 2+ , Ca(OH) 2 on the basal plane of molybdenite crystal, thus the chelating affinity of the N-heterocyclic reagents towards the lime components decided its activation ability. The DFT calculation suggested that the N-heterocycles was also able to interact with the Mo sites exposed by surface oxidation on the basal plane, thus the reactivity towards the Mo as well as the steric configuration also determined the activator effect. Therefore, the chelating ability of the activator towards the lime components/exposed Mo sites and the steric configuration of the rest alkyl group both contribute to the structure–activity relationship.
研究领域:
矿物加工
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表面化学
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浮选技术
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计算化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2023
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IF 5.2
Mengyan Tang,Yuangan Chen,Bo Feng,Kirsten Claire Corin
Separating chalcopyrite and molybdenite is difficult owing to their similarly high floatability. Accordingly, this paper considers the depressant 2-Amino-5-mercapto-1,3,4-thiadiazole (AMT), in order to separate chalcopyrite and molybdenite and investigate the relevant mechanism of AMT depression. Single-mineral flotation tests showed that when kerosene was used as the collector and AMT as the depressant, molybdenite showed excellent flotation while chalcopyrite was completely depressed. Mixed mineral flotation tests showed that separation of these two minerals could be achieved when AMT was applied as the depressant. Combining the test results of adsorption, Zeta potential , and XPS, the mechanism of AMT depression is suggested. Therefore, the adsorption mechanism of AMT on the chalcopyrite and molybdenite can be revealed. The adsorption of AMT on the chalcopyrite surface is unquestionably greater than that on the molybdenite surface. The results suggest that AMT is chemisorbed on chalcopyrite surfaces through the Cu-S bonds. By contrast, physisorption on molybdenite surfaces is through electrostatic action. Thus, selective depression of chalcopyrite can be achieved with the use of AMT. This study promises a more environmentally friendly flotation separation process for chalcopyrite and molybdenite.
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）