MINERALS ENGINEERING
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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
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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
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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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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
ADVANCED POWDER TECHNOLOGY
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2024
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IF 4.2
Jiali Chen,Peng Gao,Jie Liu,Yimin Zhu
Scheelite and calcite was firstly separated by new depressant Poly(sodium 4-styrenesulfonate) (PSS) with NaOL system. The recovery of scheelite was 87.18 % and the recovery of calcite was 5.57 % in single flotation experiments, the recovery and grade of WO 3 was 70.53 % and 61.08 % respectively in artificial mixed ore flotation under the optimal conditions of 10 mg/L NaOL, 10 mg/L PSS and pH of 8. Contact angle measurements, atomic force microscope (AFM) analysis, zeta potential analysis, fourier transforming infrared spectra (FT-IR) analysis and X-ray photoelectron spectroscopy (XPS) analysis were performed to uncover the reaction mechanism. The results showed that PSS could not adsorbed on scheelite by chemical reaction, and PSS had no impact on the further adsorption of NaOL onto the scheelite surface. Therefore, scheelite could still keep a high recovery with PSS. However, PSS could be strongly adsorbed on calcite by chemisorption between the Ca site of calcite and O site of PSS, which increased the hydrophilia of calcite and imped the further adsorption of NaOL. Therefore, it could selectively depress the flotation of calcite.
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
JOM
·
2019
·Vol. 71
·期 8
·2827-2833
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IF 2.305
Gong Dandan,Zhou Kanggen,Li Junjie,Peng Changhong,Chen Wei
Conversion of CaWO 4 to MgWO 4 by roasting scheelite with MgCl 2 is the key step for the subsequent alkaline extraction of tungsten from scheelite. In this study, the factors influencing the conversion efficiency of MgWO 4 during the roasting of synthetic scheelite and MgCl 2 were evaluated, and the reaction kinetics were explored by model fitting. The results indicate that the conversion efficiency increases with an increase in roasting temperature and magnesium chloride dosage, and that a decrease in mineral particle size also increases the conversion efficiency. Moreover, the roasting reaction between synthetic scheelite and MgCl 2 at 773–923 K fits well to the Avrami–Erofeev kinetic model, and the roasting reaction is controlled by both diffusion and chemical reaction. This study contributes to a better understanding of the roasting process of scheelite with MgCl 2 and the development of a new route for extracting tungsten from scheelite.
研究领域:
冶金化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2016
·Vol. 9
·期 3
·129
·
IF 2.728
Zhengyao Qu,Peng Liu,Xiaoyu Yang,Fazhou Wang,Wenqin Zhang,Chenggang Fei
In the present study, BiVO4sample was prepared under different pH 0.5–13 without capping agent. Different morphology characteristics were observed, such as sheet crystal structure, cross crystal structure and branching crystal structure. The mechanism of the formation of BiVO4nanostructure was discussed. Under acid condition, sheet crystal structure was obtained. The phenomenon could be attributed to polymerization of vanadate in the presence of H+. In the weak alkaline solution, across structure and branching type morphology was obtained. The photocatalytic efficiency for the samples ranked as pH 5 > pH 3 > pH 7 > pH 9 > pH 1 > pH 11 > pH 13 > blank, which is in good agreement with X-ray diffraction (XRD) result.E. colienvelop was damaged in the presence of BiVO4under visible light. The protrusion on envelop was diminished by BiVO4. Attenuated Total Reflection Fourier transformed Infrared Spectroscopy (ATR-FTIR) results suggested the intensity was weakened for the amide, phosphoric, –COO−group and C-H bond in lipopolysaccharides (LPS), peptidoglycan and periplasm molecules.Keywords:BiVO4;monoclinic scheelite structure;photocatalytic efficiency;E. coli;envelop
研究领域:
材料科学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Cleaner Production
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2018
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IF 5.651
Leiting Shen,Xiaobin Li,Qiusheng Zhou,Zhihong Peng,Guihua Liu,Tiangui Qi,Pekka Taskinen
To directly obtain solution of (NH 4 ) 2 WO 4 instead of Na 2 WO 4 is the key for developing a cleaner technology of ammonium paratungstate production. In this paper, ammoniacal ammonium carbonate solution was adopted for leaching tungsten from the converted product, a mixture of H 2 WO 4 and CaSO 4 obtained by treating scheelite with sulfuric acid . The research indicates that tungsten can be efficiently extracted in form of ammonium tungstate solution with WO 3 leaching yield of >99.5% under moderate leaching conditions. The WO 3 leaching yield is influenced by the transformation of calcium sulfate to calcium carbonate due to forming CaWO 4 through the secondary reaction between CaSO 4 and (NH 4 ) 2 WO 4 , whereas an excess (NH 4 ) 2 CO 3 (≥0.64 mol/L) can suppress the secondary reaction by facilitating the transformation. Additionally, the consumed ammonium carbonate can be recovered by treating the leaching residue with ammonium sulfate solution at above 70 °C. This work presents a cleaner and sustainable technique for producing ammonium paratungstate, with circulating the leaching reagents and bypassing the conversion of Na 2 WO 4 to (NH 4 ) 2 WO 4 .
研究领域:
化学工程
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材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
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2016
·
IF 3.698
Fuhua Li,Yapu Kang,Min Chen,Guoguang Liu,Wenying Lv,Kun Yao,Ping Chen,Haoping Huang
Characterized as by X-ray diffraction, scanning electron microscopy and UV–vis diffuse reflectance spectra techniques, BiVO 4 photocatalyst was hydrothermally synthesized. The photocatalytic degradation mechanisms of ibuprofen (IBP) were evaluated in aqueous media via BiVO 4 . Results demonstrated that the prepared photocatalyst corresponded to phase-pure monoclinic scheelite BiVO 4 . The synthesized BiVO 4 showed superior photocatalytic properties under the irradiation of visible-light. The photocatalytic degradation rate of IBP decreased with an increase in the initial IBP concentration. The degradation process followed first-order kinetics model. At an IBP concentration of 10 mg L −1 , while a BiVO 4 concentration of 5.0 g L −1 with pH value of 4.5, the rate of IBP degradation was obtained as 90% after 25 min. The photocatalytic degradation of IBP was primarily accomplished via the generation of superoxide radical ( O 2 • − ) and hydroxyl radicals ( • OH). During the process of degradation, part of the • OH was converted from the O 2 • − . The direct oxidation of holes (h + ) made a minimal contribution to the degradation of IBP.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2024
·Vol. 31
·期 11
·2435-2444
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IF 5.6
Tao Liming,Wang Jianjun,Liao Dejin,Jia Wenkai,Zhao Zihan,Che Wenfang,Qi Zhongxu,Sun Wei,Gao Zhiyong
Flotation is the most common method to obtain concentrate through the selective adsorption of collectors on target minerals to make them hydrophobic and floatable. In the hydrometallurgy of concentrate, collectors adsorbed on concentrate can damage ion-exchange resin and increase the chemical oxygen demand (COD) value of wastewater. In this work, we proposed a new scheme, i.e., desorbing the collectors from concentrate in ore dressing plant and reusing them in flotation flowsheet. Lead nitrate and benzohydroxamic acid (Pb-BHA) complex is a common collector in scheelite flotation. In this study, different physical (stirring or ultrasonic waves) and chemical (strong acid or alkali environment) methods for facilitating the desorption of Pb-BHA collector from scheelite concentrate were explored. Single-mineral desorption tests showed that under the condition of pulp pH 13 and ultrasonic treatment for 15 min, the highest desorption rates of Pb and BHA from the scheelite concentrate were 90.48% and 63.75%, respectively. Run-of-mine ore flotation tests revealed that the reuse of desorbed Pb and BHA reduced the collector dosage by 30% for BHA and 25% for Pb. The strong alkali environment broke the chemical bonds between Pb and BHA. The cavitation effect of ultrasonic waves effectively reduced the interaction intensity between Pb-BHA collector and scheelite surfaces. This method combining ultrasonic waves and strong alkali environment can effectively desorb the collectors from concentrate and provide “clean” scheelite concentrate for metallurgic plants; the reuse of desorbed collector in flotation flowsheet can reduce reagent cost for ore dressing plants.
研究领域:
矿物加工工程
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环境科学与工程
✓ 已验证
DOI
高影响因子
MINERALS ENGINEERING
·
2019
·
IF 3.315
Fei Lyu,Wei Sun,Sultan Ahmed Khoso,Chenyang Zhang,Runqing Liu,Li Wang,Jiande Gao
In this study, propyl gallate (propyl 3,4,5-trihydroxybenzoate; PG) was introduced as a collector for scheelite. The adsorption mechanism on the scheelite surface was investigated by computational and experimental methods, including first principle calculations and Fourier transform infrared (FTIR) spectroscopy. Flotation experiments were conducted to investigate the flotation performance of PG on scheelite. Ethyl p-hydroxybenzoate (EPHB) and ethyl 3,4-dihydroxybenzoate (EDHB), acting separately as collectors for scheelite, were also investigated for comparison. Our results consistently demonstrated that PG chemisorbed onto the scheelite surface by forming a five-member ring through its ortho oxygens. As speculation, the chelating ability of PG was greater than that of EDHB, and EPHB cannot coordinate to Ca(II), which was in excellent agreement with FTIR results. The flotation results showed that PG exhibited an excellent collecting ability for scheelite, followed by the weaker collecting ability of EDHB. EPHB had nearly no ability to collect scheelite, thus confirming the first principle calculation and FTIR analysis. In addition, PG has a stronger ability to collect scheelite than BHA without activation by any metallic ions. Overall, PG is a promising scheelite collector for application and the activate polyphenolic hydroxyl groups offer a new insight for the development of flotation collectors.
研究领域:
矿物加工工程
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理论化学
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材料科学
✓ 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）