Minerals
·
2021
·Vol. 11
·期 10
·1079
·
IF 2.644
Penggang Wei,Liuyi Ren,Yimin Zhang,Shenxu Bao
The recovery of fine wolframite is low when using traditional flotation that does not use a microbubble. In this study, a microbubble was introduced into the fine wolframite flotation system; −20 μm wolframite was used as an experiment sample and octyl hydroxamic acid as the collector. The recovery of microbubble flotation reached 84.07%, which is about 12.04% higher than that of traditional flotation. A single-factor flotation experiment, high-speed camera analysis, and SEM (Scanning Electron Microscopy) analysis were used to study the influence of microbubbles on the flotation of fine wolframite. The results show that fine wolframite will more easily agglomerate under the action of microbubbles. The octyl hydroxamic acid adsorbed on the surface of wolframite treated with microbubbles is denser and more abundant.Keywords:wolframite;fine particles;microbubble;flotation
研究领域:
矿物加工工程
·
化学工程
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Xun Wang,Ruiqi Xie,Jie Liu,Yimin Zhu
Owing to the similar surface properties of scheelite and fluorite , the separation of them is very difficult by only using the traditional collectors of fatty acids. In this study, Nitrilotri(methylphosphonic acid) (ATMP) was used as a depressant to realize the efficient separation of these two minerals. The separation performance and the adsorption mechanism of ATMP on scheelite and fluorite were explored by the flotation experiments and surface analyses. Flotation results indicated that ATMP exhibited strong inhibition on the fluorite flotation but did not affect that of scheelite, and a satisfactory separation of scheelite from fluorite was achieved at the reagent regime of 60 mg/L ATMP, 40 mg/L sodium oleate (NaOL) and pH 10.0. Zeta potential measurements and AFM detections showed that the intense adsorption of ATMP onto fluorite was occurred and which could prevent the subsequent adsorption of NaOL on fluorite, while the adsorption of ATMP onto scheelite was weak and the further interaction between NaOL and scheelite was hardly influenced by it. Moreover, Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) analyses confirmed that the interaction between calcium ions exposed on fluorite surface and the phosphate groups of ATMP accounted for the chemisorption of ATMP on fluorite. As a result, ATMP can be selected as a potential depressant for separating scheelite from fluorite.
研究领域:
矿物加工工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
·
2021
·
IF 6.064
Yuxi Lu,Shuai Wang,Hong Zhong
Wolframite is often associated with calcium bearing minerals, leading to low grade, while conventional anionic collectors are hard to realize their efficient flotation separation, thus the effective structural modification of cationic collectors provides a new insight into enhancing the comprehensive development of wolframite resources. In this study, a surfactant 3-dodecyloxy propyl amidoxime (DOPA) was designed and first used as the collector in flotation separation of wolframite from fluorite and calcite. Computational calculations basically proved the correctness of predictions about the performances of DOPA. Micro-flotation tests indicated that compared to DDA and conventional anionic collector benzohydroxamic acid (BHA), DOPA possessed superior collecting ability to wolframite and excellent selectivity against fluorite and calcite at low concentration, with no frother or activator employed, which is supposed to be an efficient collector for separating wolframite from calcium bearing minerals. The separation mechanisms of DOPA between wolframite and fluorite/calcite were further probed, revealing that besides the electrostatic attraction between DOPA and wolframite, DOPA could chemisorb onto wolframite surfaces by forming five-membered ring toward the surface cation site Fe or Mn, with no significant interaction observed on fluorite/calcite surfaces, resulting to the excellent separation performance.
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
MINERALS ENGINEERING
·
2021
·
IF 4.765
Jie Liu,Xun Wang,Yimin Zhu,Yuexin Han
The selective separation of scheelite from fluorite is difficult because of their similar surface properties. In this study, diethylenetriaminepentaacetic acid (DTPA) was used as a novel depressant for the efficient removal of fluorite from scheelite, and its depression effect and mechanism were systematically investigated by conducting micro-flotation experiments and a series of surface analyses. The micro-flotation experiments showed that the floatability of fluorite was significantly reduced by DTPA, whereas that of scheelite was minimally affected. Zeta potential measurements revealed that DTPA selectively adsorbed on fluorite surface and decreased the zeta potentials, whereas the zeta potentials of scheelite were negligibly influenced by DTPA. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy further proved that the interaction between DTPA and the fluorite surface was chemisorption, and in the adsorption configuration, the carboxyl groups of DTPA chelated with Ca sites on the fluorite surface. Additionally, an electrical analysis showed that electrostatic attraction facilitated the adsorption of DTPA on the fluorite surface. The adsorption of DTPA on fluorite surface could strongly inhibit the further adsorption of NaOL on fluorite surface, and therefore significantly depressed the floatability of fluorite. In contrast, the interaction between DTPA and scheelite was very weak and was impeded by steric hindrance caused by WO 4 2- and electrostatic repulsion. Therefore, DTPA has the potential to act as a depressant for the effective separation of scheelite from fluorite.
研究领域:
矿物加工工程
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
Mineral Processing and Extractive Metallurgy Review
·
2020
·
IF 2.785
Zhiyong Gao,Jian Deng,Wei Sun,Jianjun Wang,Yunfeng Liu,Fengping Xu,Qinghong Wang
Scheelite and calcite are usually intergrown calcium minerals that are separated via froth flotation. However, their selective separation remains difficult because of their similar surface properties. 2-phosphonobutane −1, 2, 4-tricarboxylic acid (PBTCA or H5L) is widely used in water treatment due to its low phosphorus content and efficient anti-scaling performance. With its excellent calcium-chelating ability, PBTCA was used as a novel depressant to selectively separate scheelite from calcite in this study. The flotation results of single mineral, binary mixed minerals, and real ore showed that PBTCA could selectively depress calcite at pH 9.0 using sodium oleate as collector. The results of zeta potential measurements, solution chemistry calculation, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and density functional theory calculation indicated that the dominant form of PBTCA was L5-. This anion had a stronger adsorption on negatively charged calcite surfaces through electrostatic interaction. Higher Ca density and stronger Ca activity on calcite promote the adsorption of L5-. Moreover, the active O atoms in L5- could better match with two Ca sites on calcite in the interatom distance. Thus, PBTCA provides a new option for calcite depressants and has great industrial application potential.
研究领域:
矿物加工工程
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表面化学
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材料科学
✓ 已验证
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2023
·
IF 5.7
Ruiqi Xie,Zhihui Zhao,Xun Wang,Xiong Tong,Xian Xie
Background Fluorite and scheelite are main resources for fluorine and tungsten respectively, which are usually associated with each other, and the separation of them has important strategic meaning. For the first time, scheelite and fluorite were separated by using nitrilotriacetic acid (NTA) as depressant. Methods The effects of NTA on the flotation of scheelite and fluorite were investigated by flotation experiments. The selective adsorption mechanism of NTA on fluorite were revealed by atomic force microscope (AFM), zeta potential measurements, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). Significant findings NTA could achieve the efficient separation of scheelite from fluorite. Under the optimal separation conditions, the recovery of scheelite concentrate is 73.59 % and the grade of CaWO 4 is 73.19 %, and the recovery and CaF 2 grade of fluorite in tailings was 74.71 % and 79.44 % respectively. Mechanism study showed that although NTA had carboxy groups, NTA could not be adsorbed on scheelite surface due to the electrostatic repulsion and steric effect. However, NTA was strongly chemisorbed by calcium on fluorite, covering calcium groups and hiding the further adsorption of NaOL. Thus, NTA selectively disturbed NaOL adsorption and decreased the floatability of fluorite and realized the scheelite-fluorite separation.
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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Shaoyan Zhang,Jingzhong Kuang,Mingming Yu,Weiquan Yuan,Zheyu Huang
Effect of ultrasound on solution properties of sodium silicate (Na 2 SiO 3 ) was investigated in this study to separate scheelite from fluorite effectively. The effect of ultrasonicated sodium silicate solution on flotation separation of scheelite and fluorite and selective adsorption mechanism of scheelite and fluorite were also explored. Ultrasonicated Na 2 SiO 3 was found to significantly improve the scheelite grade, and the adsorption capacity and adsorption heat of Na 2 SiO 3 on fluorite surface were significantly improved, which can enhance the inhibitory effect. The ultrasonic cavitation effect promoted electrolysis of Na 2 SiO 3 in the solution, forms additional SiO 3 2− and SiO 4 4− ions, reduced surface tension of the solution, and thus reduced adhesion work between Na 2 SiO 3 and fluorite. Fourier transform infrared (FTIR) Spectroscopy and X-ray photoelectron spectroscopy (XPS) analyses showed that sodium silicate was obviously adsorbed on the surface of fluorite, elemental Si content of the fluorite surface increased considerably and to a higher level than that of the scheelite surface, and Ca 2+ binding energy shifted less noticeably on the scheelite surface than that on the fluorite surface. These results indicated that the higher adsorption strength for Na 2 SiO 3 on the fluorite surface than that on the scheelite surface hindered the adsorption of benzohydroxamic acid (BHA) on the fluorite surface and ultrasound promoted selective separation of scheelite and fluorite.
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Qifang Zheng,Liuyang Dong,Peilun Shen,Dianwen Liu
Citric acid (CA) exhibits weak inhibitory on some oxidized gangue minerals owing to its relatively few hydrophilic polar groups ( OH and COOH). This study investigate the synergistic mechanism of ferrous ions (Fe 2+ ) to enhance both the selective adsorption capacity and stability of CA. The separation of scheelite and cassiterite through a flotation process was successfully achieved using a Fe 2+ /CA mixed depressant. Micro-flotation test results revealed that with the addition of Fe 2+ /CA, 84.60 % of scheelite and 23.64 % of cassiterite were recovered in the foam concentrate, with grades of 66.26 % and 17.73 %, respectively. Fe 2+ /CA had a strong depressing effect on cassiterite, resulting in a 69.30 % decrease in its recovery and a 20.33 % decrease in its grade. This indicates the effective separation of scheelite from cassiterite. Fe 2+ /CA exhibited a high adsorption affinity for the cassiterite surface, which mainly comprised L 3– , Fe 2+ , and FeOH + components. Additionally, the FeOH + complex, formed from the pre-reaction between Fe 2+ and CA, exhibited significant chemical adsorption at the Sn active sites, thereby depressing cassiterite. The high-intensity adsorption peaks at cracks and the significant increase in the normalized intensity of FeOH + on the cassiterite surface indicated that the FeOH + complex had stronger adsorption on cassiterite and selectively depressed cassiterite. This enhanced both the selective adsorption capacity and stability of CA on the cassiterite surface. The Fe 2+ /CA mixed depressant achieved efficient flotation separation of scheelite and cassiterite.
研究领域:
矿物加工工程
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2012
·Vol. 95
·期 10
·3214-3219
·
IF 2.272
Haoyi Wu,Yihua Hu,Fengwen Kang,Nana Li,Guifang Ju,Zhongfei Mu,Zhongfu Yang
Praseodymium (Pr 3+ ) with rich f energy levels can generate various visible emissions, but the luminescence of Pr 3+ in a CaWO 4 matrix has not yet been studied. In this article, the phosphors of Pr 3+ -doped CaWO 4 were synthesized via a high temperature solid-state reaction, and the photoluminescence (PL) and afterglow properties of Pr 3+ in the CaWO 4 matrix were investigated. The phase identifications of the samples show that an impure monoclinic phase appears when the Pr 3+ concentration is high. The results of PL exhibit the usual Pr 3+ characteristic emissions as well as an emission that is produced by the charge transfer from 5 d of W 6+ to 2 p of O 2− under a shortwave ultraviolet excitation. An intermediate energy transfer occurs during the charge transfer which induces the afterglow. The quenching point of Pr 3+ in CaWO 4 is 2 mol%, corresponding to the critical energy transfer distance of ~20 Å. The quenching mechanism in the Pr 3+ -doped CaWO 4 is the dipole-dipole interaction. The Ca 2+ vacancies ( V Ca ) are the defects that induce the traps and capture holes from O 2− . The thermal energy of holes liberation from V Ca to O 2− results in the charge transfer accompanied by an energy transfer to Pr 3+ , and consequently generates the afterglow. The experimental results also show that the afterglow characteristics of Pr 3+ are prolonged by incorporating Pr 3+ in the CaWO 4 matrix.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Longfu Dai,Jian Liu,Da Li,Jiamei Hao,Hulin Gao
The hydroxamic acid reagents are extremely pervasive in the collector of scheelite flotation. The high flotation cost is caused by its large dosage and high price. A novel auxiliary collector 4-methodybenzoicacid (4-MBA) was used in combination with benzohydroxamic acid (BHA) to optimize the flotation reagents system for scheelite in the study. A single 4-MBA has weak collection capacity for scheelite. Nevertheless, the combination of 4-MBA and BHA optimized the flotation system of scheelite by ensuring its recovery and reducing the reagent consumption. The results of solution surface tension and contact angle measurements showed that the surface tension of the mixed reagent solution is a relatively lower and the hydrophobicity of the scheelite surface is a relatively higher in the BHA and 4-MBA mixed reagent system. Additionally, a synergistic effect between BHA and 4-MBA on Pb 2+ activated scheelite is revealed by the Zeta potential measurements, infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The addition of 4-MBA promoted the physical and chemical adsorption of BHA. The results of molecular dynamics simulation (MDS) further explained that the collector adsorption layer of the surface of scheelite (1 1 2) is more compact under BHA and 4-MBA mixed reagent system, which prevents the vertical entry of water phase and improves the hydrophobicity of scheelite. Finally, the bench-scale flotation experiment verified that the addition of 4-MBA enhanced scheelite flotation with BHA, and decrease the flotation cost of scheelite.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
DOI
高影响因子
Minerals
·
2022
·Vol. 12
·期 5
·530
·
IF 2.818
Chenhu Zhang,Haijun Wu,Wei Sun,Yuehua Hu,Chengyong Wang,Shan Zhu,Peng Chen
The recovery of scheelite from calcium-bearing carbonate ores by foam flotation is challenging due to its low separation efficiency. This study investigated the effect of pentasodium diethylenetriaminepentaacetate (PD) on the surface properties of scheelite and fluorite. For this purpose, we performed micro-flotation tests and carried out zeta potential measurements, as well as Fourier transform infrared (FT-IR) and X-ray photoelectron (XPS) spectroscopic measurements, in order to analyze the surface properties of these minerals. The addition of PD as a novel depressor significantly improved the effect of fluorite and sodium oleate (NaOl) on the flotation-based scheelite recovery and separation from fluorite. PD was spontaneously adsorbed onto fluorite through electrostatic and chemical adsorption. By contrast, PD did not appear on the scheelite because of the reaction conditions, surface site, and steric hindrance. X-ray photoelectron spectroscopy measurements and a solution chemistry analysis were used for the determination of the PD-selective adsorption mechanism and key factors derived from multi-layer adsorption onto fluorite, which completely hindered that of NaOl.Keywords:scheelite;fluorite;selective flotation;pentasodium diethylenetriaminepentaacetate
研究领域:
矿物加工工程
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表面化学
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2024
·
IF 4.9
Guangsheng Zeng,Wei Weng,Shuiping Zhong,Xiaopeng Chi,Jiaozhong Cai,Wen Tan,Junnan Chen
The novel amidoxime-based collectors, 4-pyridylamidoxime (PA), 3-ethyl-4-pyridylamidoxime (EPA), and 3-methyl-5- tert -butyl-4-pyridylamidoxime (MBPA), were introduced in the lead-free flotation separation of wolframite from quartz and calcite. Compared with PA, EPA, and the traditional collector benzohydroxamic acid (BHA), MBPA exhibited a better separation and recovery capacity to wolframite ore. 4.0 × 10 -4 mol/L MBPA recovered more than 80 % wolframite, ∼24 % calcite, and ∼ 26 % quartz at pH 8.0 without Pb 2+ ions. Under the same conditions, BHA only floated out less than 35 % wolframite. The adsorption amount results exhibited a stronger adsorption ability of MBPA than BHA on wolframite surface. Further, the results of zeta-potential, FTIR, XPS and density functional theory (DFT) calculation revealed that MBPA could chemisorb on wolframite surface to form −N-Fe and −O-Fe bonds. MBPA had stronger electron-donating ability and weaker electron-accepting ability than BHA, which exhibited higher reaction activity. It was clear that MBPA was an excellent collector in the lead-free flotation separation of wolframite from calcite and quartz.
研究领域:
矿物加工工程
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材料化学
✓ 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）