MATERIALS & DESIGN
·
2018
·
IF 4.525
Liwang Liu,Hong Li,Zirui Liu,Ya-Hong Xie
By hot-injection method with altering the dose of oleylamine (OAm) in a reaction system, CuInS 2 (CIS) nanocrystal with tunable structure and band gap is synthesized. Through various measurements, including X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), it is demonstrated experimentally that when the dose of OAm is relatively high (2.0 and 2.5 ml in this work), the combination phase of pseudo-chalcopyrite/wurtzite are obtained with a surprising existence of nanotwins. Besides, the molar fraction of wurtzite is larger in the sample using 2.5 ml OAm in the reaction system. However, when the dose of OAm becomes low, (0, 1.0 and 1.5 ml), pure zinc-blende CIS pyramidal quantum dots (QDs) can be prepared. This indicates that oleylamine promotes the formation of wurtzite structure. In addition, the band gap is larger with increasing of OAm, following the quantum refinement effects. This work serves as a facile method of synthesizing CIS nanocrystal with tunable structure and band gap, which will be possibly applied in the fabrication of their optoelectronic devices.
研究领域:
材料科学
·
纳米技术
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
Geochemistry
·
2024
·
IF 2.6
Guanghui Li,Zheyi Zhang,Qian Wei,Fen Jiao,Congren Yang,Wei Li,Wenqing Qin
In this study, a new process of pre-flotation decarbonization‑lead flotation‑zinc flotation was proposed to recover valuable metals from a lead‑zinc ore in Guizhou by beneficiation and to determine a reasonable and economic beneficiation process. The results of the study demonstrate that the novel process aids in the flotation of lead and zinc ores in two ways: (1) pre-decarbonization using MIBC (methyl isobutyl carbinol) and kerosene synergistically achieved the lowest loss of lead recovery of 1.94 % and zinc recovery of 1.14 % in the decarbonized product. (2) the successful separation and retrieval of lead and zinc metals were accomplished via a preferential flotation technique, using several combinations of reagents. This procedure yielded a lead recovery rate of 87.64 % and a zinc recovery rate of 94.09 %.
研究领域:
矿物加工工程
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2019
·
IF 3.413
Bin Luo,Quanjun Liu,Jiushuai Deng,Li Yu,Hao Lai,Chao Song,Shimei Li
Beneficiation of zinc from low-grade oxidized zinc ores has become the focus of recent studies. Sulfidation is an important process to recover zinc from oxidized zinc ores in flotation . Although some studies have reported on the sulfidation-flotation of smithsonite, the effect of sulfide ions on sulfide film thickness remains unknown when the oxidized zinc ores start floating and achieve excellent flotation. In this work, the influence of sulfur ions on smithsonite flotation in a dodecylamine system were investigated by micro-flotation experiments, inductively coupled plasma-atomic emission spectrometry (ICP-AES), zeta potential measurements, X-ray photoelectron spectroscopy (XPS), and time-of-flight secondary ion mass spectrometry (TOF-SIMS). Micro-flotation experiment results show that smithsonite starts floating after treatment with a low S concentration of 5 × 10 −5 mol/L, while excellent flotation was obtained following treatment with a high S concentration of 5 × 10 −4 mol/L. Compared to the low S solution, excellent hydrophobicity of smithsonite was obtained owing to the adsorption of more sulfide ions, making the mineral surface potential more negative, and forming a thicker heterogeneous zinc-sulfide film that primary consists of zinc monosulfide and zinc polysulfide . The zinc-sulfide film thickness on the smithsonite surface was approximately 7.79 nm when the smithsonite started floating, while excellent floatation was obtained as the zinc-sulfide film thickness reached about 12.13 nm.
研究领域:
矿物加工工程
·
冶金工程
✓ 已验证
DOI
高影响因子
Minerals
·
2019
·Vol. 9
·期 8
·463
·
IF 2.25
Yuqing Huang,Wanzhong Yin,Rongdong Deng,Dingquan Xing,Feng Rao
The conventional sulfidation-xanthate flotation process that consists of sulfidization with sodium sulfide, activation by heavy-metal ions, and collection with xanthate is not sufficiently efficient for treating hemimorphite, and the dosages of the sulfurizing reagent and metal ions are large. In this study, the sulfidation flotation (Pb2++ Na2S + Pb2++ xanthate) of hemimorphite was strengthened by pretreating with Pb2+before sulfidation. Microflotation test results indicated that the recovery of hemimorphite increased by 5–10% after pretreatment with Pb2+. The comprehensive results of adsorption experiments, scanning electron microscopy–energy-dispersive X-ray spectroscopy, atomic force microscopy, and X-ray photoelectron spectroscopy indicated that a large amount of Pb2+was adsorbed on the hemimorphite surface and entered the lattice, forming Zn(4−x)PbxSi2O7(OH)2·H2O. The newly formed component had an increased amount of surface sulfidation active sites and had the effect of induced crystallization, making the surface more effective for sulfidation. After the Pb2+was added to the pulp, a large number of uniform and dense PbS species were formed on the hemimorphite surface, increasing the number of adsorption sites for xanthate and reducing the competitive adsorption of residual S2−on the xanthate.Keywords:hemimorphite;flotation;strengthening sulfidation;pretreatment;lead ion
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2023
·
IF 4.8
Jiahui Wu,Longhua Xu,Donghui Wang,Kai Xue,Xinzhang Shi,Lin Peng,Jiushuai Deng
Removing calcite is a tricky problem in smithsonite flotation because of its better floatability. 1-Hydroxyethylidene-1,1-diphosphonic acid (HEDP), a scale inhibitor in water treatment industry, was chosen as a calcite depressant. This study validated the effectiveness of HEDP in separating smithsonite from calcite by flotation using sodium oleate (NaOL) as the collector, and obtained a 70% recovery difference in a single mineral flotation. Artificial mixed mineral flotation obtained a concentrate with a grade of 44% and a recovery of more than 80%. Zeta potential, Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) tests were conducted to obtained some crucial information on the adsorption of NaOL and HEDP, demonstrating that the adsorption of HEDP on calcite surfaces was stronger than smithsonite. The intense adsorption of HEDP on calcite surfaces was attributed to chelation with surface calcium sites. Quantum chemical calculations suggested that the selectivity of HEDP was closely related to the phosphate groups. HEDP was chemically adsorbed on calcite surface by complexing with calcium sites to form six-membered ring chelate. Partial oxygen atoms of phosphate groups dominated in the reaction with calcium sites, and the deprotonation of phosphate groups enhanced the reactivity.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2022
·
IF 10.508
Linxi Wang,Xudong Qian,Yang Ren,Hairui Lei,Xiaofei Hu,Dongdong Chen,Jiongzhao Li,Xiaogang Peng
The CdS shells are epitaxially grown onto monodisperse zinc-blende CdSe core nanocrystals in octadecene mixed with fatty amines, with the volume fraction of fatty amines in the epitaxy solution (VNH2) varying between 0 and 100%. The shape─except the nanoplatelets from the reactions with medium VNH2 (especially 20% VNH2)─and surface ligands of the resulting CdSe/CdS core/shell nanocrystals from all reactions can be unified through a two-step surface treatment. The internal lattice defects originated from zinc-blende/wurtzite stacking fault(s), i.e., wurtzite lattice domain(s) in the CdS shells and twin fault(s) in the zinc-blende region, can be systematically controlled by varying the VNH2 and remain unaltered during the surface treatments. Both twin faults and wurtzite CdS lattice domains neither affect the electronic structure of the core/shell nanocrystals nor create internal electronic defects for the nanocrystals. Photoluminescence decay dynamics of the dot-shaped core/shell nanocrystals with solely twin faults can be mono-exponential and near-unity radiative decay, but photoluminescence of those with wurtzite CdS domains would always decay with double-exponential even if the photoluminescence quantum yield is unity. The results here imply that the most common lattice defects related to the stacking faults for II–VI and III–V semiconductor nanocrystals can be managed for achieving high-quality optical properties.
研究领域:
材料科学
·
纳米技术
·
半导体物理
·
光学性质
✓ 已验证
DOI
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2022
·
IF 3.752
Qian WEI,Liu-yang DONG,Cong-ren YANG,Xue-duan LIU,Fen JIAO,Wen-qing QIN
Lime (CaO) and sodium humate (NaHA) were used as the combined depressant for arsenopyrite pre-treated by CuSO 4 and butyl xanthate. Micro-flotation tests show that the combined depressant CaO and NaHA achieved the selective depression of arsenopyrite. Closed-circuit lab-scale test results indicate that the synergistic effect of CaO+NaHA achieved a satisfactory flotation separation of sphalerite and arsenopyrite, for which the Zn grade and recovery of Zn concentrate were 51.21% and 92.21%, respectively. Contact angle measurements, adsorption amount measurements and X-ray photoelectron spectroscopy analysis indicate that the dissolved calcium species (mainly as Ca 2+ ) were adsorbed on the mineral surfaces, thereby promoting NaHA adsorption. Moreover, the surface of the arsenopyrite absorbed more amount of calcium species and NaHA than that of the sphalerite, thereby accounting for the strong hydrophilic surface of arsenopyrite. The adsorption of NaHA on arsenopyrite was mainly chemical adsorption through its carboxyl groups and Ca atoms, whereas that on sphalerite surface was relatively weak.
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2018
·
IF 2.707
Yanfei Chen,Guofan Zhang,Mengtao Wang,Qing Shi,Dezhi Liu,Qi Li
Sulphidisation xanthate flotation is a common process in dealing with zinc oxide minerals and sulphidisation is the key procedure in the zinc mineral recovery. In this study, the effect of Ca 2+ on the sulphidisation flotation of smithsonite was investigated by flotation tests. The results show that the presence of Ca 2+ impairs the sulphidisation flotation of smithsonite. Adsorption studies and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS) analysis illustrate that at pH 9.5, where the sulphidisation process is routinely performed, the positively charged Ca(OH) 2(s) , Ca(OH) 2(s) , and CaOH + produced due to hydrolysis and precipitation of Ca 2+ will preferentially adsorb onto smithsonite surface, preventing the adsorption of sulfur ions. Thus, the insufficient sulphidisation on smithsonite surface cannot promote the mineral flotation performance. Interestingly, sodium carbonate can eliminate adverse effect of Ca 2+ by charge reversal. For its reactivity with Ca 2+ , the formation of negatively charged calcium carbonate ceases the adsorption of calcium onto smithsonite surface as a consequence of electrostatic repulsion. As thus, the sulphidisation flotation of smithsonite is regained.
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Minerals
·
2025
·Vol. 15
·期 1
·82
·
IF 2.2
Longqian Ni,Jinfang Lv,Lingyu Kong,Longwei Qin
Sphalerite often co-exists with dolomite, a carbonate mineral containing calcium and magnesium. In the flotation process of sphalerite, dolomite entering into the concentrate will have a considerable negative impact on the subsequent smelting. Therefore, the effects of sodium silicate on the flotation separation of sphalerite and dolomite and its mechanism were investigated in this study. It was found that alkaline conditions and the addition of sodium silicate were conducive to the flotation separation of sphalerite and dolomite. Under alkaline conditions, sodium silicate improved the hydrophobicity of sphalerite and the slurry turbidity. The yield stress and apparent viscosity were significantly reduced when dolomite was present in slurry. In addition, the surface electrical properties of dolomite shifted from positive to negative with an increase in the dosage of sodium silicate at pH 11, leading to electrostatic repulsion between sphalerite and dolomite. EDLVO results indicated that the total interaction energy between dolomite and sphalerite particles was repulsive when sodium silicate was present. This study provided a theoretical basis for the flotation separation of sphalerite and dolomite.
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2024
·
IF 5.5
Linquan Dai,Bo Feng,Yutao Guo
Background Sphalerite and galena often exist in mixed form and are difficult to separate effectively. The effect of surface oxidation behavior regulation on the depression of calcium lentisulfonate (CLS) was studied in galena and sphalerite. Methods Flotation experiment, contact angle experiment, X-ray photoelectron spectroscopy (XPS) analysis and microcalorimetric experiment were used to study the effect and mechanism of modulation of surface oxidation behaviour on CLS on the depression of galena flotation. Significant findings The results show that CLS can depress both galena and sphalerite. The oxidizing agent H 2 O 2 oxidizes galena significantly faster than sphalerite. The treatment with H 2 O 2 induces the formation of more oxidation products, such as PbSO 4, on the surface of galena, enhances the adsorption of CLS and makes the surface of galena hydrophilic, thus reducing the recovery of galena in the flotation process. On the other hand, the treatment of the activator ethylenediaminetetraacetic acid (EDTA) reduces the amount of oxidation products ZnSO 4 on the sphalerite surface, and CLS loses the active site that can be adsorbed on the galena surface, making the galena surface hydrophilic. In view of the huge hydrophobicity difference between sphalerite and galena, flotation separation is achieved.
研究领域:
矿物加工工程
·
材料科学与工程
✓ 已验证
产品关联
DOI
高影响因子
ADSORPTION SCIENCE & TECHNOLOGY
·
2021
·
IF 4.232
Bo Yang,Xian Xie,Xiong Tong,Lingyun Huang
Terpenic oil (TO) is commonly used as a flotation frother for the selective separation of sulfide minerals. As a frother, most reports have mainly focused on its effect on froth stability and froth entrainment, whereas its influence on the floatability of sulfide minerals has received little attention. In this work, the influence of TO on the flotation behavior of sphalerite was investigated by using microflotation tests, contact angle and zeta potential measurements, and FT-IR and SEM-EDS analyses. Microflotation tests conducted in a modified Hallimond tube indicated that compared with the collector potassium butyl xanthate (KBX), the flotation recovery of sphalerite was significantly increased when TO was added to the pulp, but the recovery of Cu-activated sphalerite with the addition of TO was lower than that with the addition of KBX. Contact angle measurements demonstrated that the contact angle of sphalerite was distinctly increased by the addition of TO, but the contact angle of sphalerite treated with TO was lower than that treated with KBX after Cu activation. Zeta potential measurements demonstrated that the zeta potential of sphalerite particles was slightly decreased when treated with TO, and the isoelectric point (IEP) was decreased from 3.3 to 3.1 due to the interaction of TO with sphalerite particles. FT-IR and SEM-EDS confirmed that TO could be adsorbed on the sphalerite surface on the formation of the oil film due to its low solubility, thereby increasing the surface hydrophobicity of the sphalerite. In addition, the TO absorbed on the surface acts as a bridging role and promotes the hydrophobic agglomeration of sphalerite particles. These results suggest that except for froth entrainment, the influence of TO on the flotation behavior of sphalerite may be another reason for the misreporting of sphalerite in concentrates.
研究领域:
矿物加工工程
·
材料科学与工程
✓ 已验证
DOI
高影响因子
HYDROMETALLURGY
·
2019
·
IF 3.465
Yisheng Zhang,Hongbo Zhao,Yanjun Zhang,Hongwei Liu,Huaqun Yin,Jiushuai Deng,Guanzhou Qiu
Sulphide minerals commonly existing in the form of polymetallic ores are the essential objects in the fields of acid mine drainage and biohydrometallurgy. Although interactions between different minerals have been studied extensively, there are no research reports on the interactions between marmatite and chalcocite. Hence, the interactions between marmatite and chalcocite in biotic/abiotic leaching and electrochemical systems were investigated. Electrochemical tests show that the open circuit potential of marmatite is 39 mV lower than that of chalcocite. Theoretically, marmatite should react as an anode in this galvanic couple, thus dissolving faster. However, leaching results suggest that the introduction of marmatite promotes chalcocite dissolution but its own dissolution was impeded, despite a slight acceleration observed during the early stage in abiotic systems. The results of this study reveal that the solution factors including oxidation-reduction potential, iron concentrations, and microbial concentrations might have significant effects that are more potent than the galvanic effect. The unpredictable inhibition of marmatite dissolution might be attributable to the existence of excess Cu 2+ liberated from the chalcocite. A further deduction proposed that a synergistic dissolution of marmatite and chalcocite can be achieved by adjusting their mass ratios to attain a suitable Cu 2+ concentration.
研究领域:
矿物学
·
生物冶金学
✓ 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）