Minerals
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2021
·Vol. 11
·期 6
·555
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IF 2.644
Chenhu Zhang,Jiande Gao,Yuehua Hu,Wei Sun,Fei Lv,Zhenjun Liu
Fluorite is a nonrenewable mineral used to produce anhydrous hydrofluoric acid (AHF) and aluminum fluoride. The demand for low-grade fluorite powder (CaF2< 97%) has fallen sharply owing to the current market conditions. Therefore, a large number of fluorite concentrates have been improved by acid leaching. While this approach can efficiently remove CaCO3from fluorite concentrate, the SiO2content, which significantly affects AHF consumption during the production of HF or aluminum fluoride, cannot be completely removed. To solve this problem, in this study, we used reverse flotation before leaching the fluorite concentrates. Subsequently, the feasibility of reverse flotation desilication was determined. The obtained results of the ZP (zeta potential) measurements, solution chemistry analysis, FTIR (Fourier transform infrared spectroscopy) analysis, and micro-flotation tests indicated that employing dodecylamine as the collector and citric acid as the depressor could effectively separate sericite from fluorite. The batch flotation experiment and the pilot test were conducted in Chenzhou (Hunan, China) followed by their operation in Xinyuan Mining Co. Ltd., which produces monolithic fluorite ore on the large scale in Asia. Notably, we found that the contents of both SiO2and Al2O3were from 2.82%, 1.17% reduced to 1.28%, 0.74% in the batch flotation experiment. The results of the pilot test showed that the new reverse flotation + leaching technology could dramatically reduce the potential environmental impact and costs, thereby significantly improving the economic benefits by satisfying the requirements of the market.Keywords:fluorite;desilication;reverse flotation;leaching
研究领域:
矿物加工工程
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环境科学与工程
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产品关联
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
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DOI
高影响因子
MINERALS ENGINEERING
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2021
·
IF 4.765
Xun Wang,Jie Liu,Yimin Zhu,Yanjun Li
To achieve the efficient flotation separation of cassiterite from fluorite, an eco-friendly depressant, the disodium salt of adenosine 5′-triphosphate (Na 2 ATP), was employed for the selective depression of fluorite. The performance of Na 2 ATP as a depressant in the flotation of cassiterite and fluorite was evaluated by micro-flotation experiments in a sodium oleate (NaOL) system. The flotation tests revealed that Na 2 ATP significantly depressed the flotation of fluorite compared to that of cassiterite, and excellent separation was achieved using 1.0 mM Na 2 ATP and 0.14 mM NaOL at pH 8.02. Moreover, the mechanism of the selective depression Na 2 ATP on the two minerals was revealed by surface analyses, revealing that chemisorption between the phosphate group of Na 2 ATP and the calcium ions on the fluorite surface was responsible for the selective adsorption of Na 2 ATP on fluorite, and the significant pre-adsorption of Na 2 ATP onto the fluorite surface impeded the further adsorption of NaOL. However, because Na 2 ATP was adsorbed on cassiterite by physisorption, which is relatively weak, the strong chemisorption of NaOL on cassiterite occurred regardless of pre-treatment with Na 2 ATP. Furthermore, density functional theory calculations revealed that the adsorption mode of Na 2 ATP to be “horizontal” and to occur at multiple calcium-ion sites on the fluorite surface. In summary, Na 2 ATP is a suitable high-efficiency depressant for the separation of cassiterite from fluorite by direct flotation.
研究领域:
矿物加工工程
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表面化学
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高影响因子
Minerals
·
2022
·Vol. 12
·期 8
·996
·
IF 2.818
Yupeng Qian,Xuan Qiu,Tiewei Shen,Yangyang Huai,Bin Chen,Zhen Wang
In the flotation of semi-soluble minerals such as calcite and fluorite, Ca2+is one of the common dissolved components influencing the collector adsorption behaviors on the mineral surfaces. However, there is very limited research focusing on how the dissolved Ca2+affects the separation of fluorite and calcite. In the study, with sodium oleate (NaOL) as a collector and tannic acid (TA) as a depressant, a flotation test, zeta potential measurement, and adsorption experiment in the presence of Ca2+were conducted. Flotation tests indicated that in the presence of Ca2+, fluorite and calcite were both significantly depressed by TA, leading to difficulty in the separation of the two minerals. It was also found that the depression effect on fluorite flotation was minimized with a high concentration of NaOL. Zeta potential measurement and the adsorption experiment results are consistent with the flotation results, revealing that it is only in the low concentration of NaOL that the flotation of fluorite was depressed by TA in the presence of Ca2+. Specifically, in the low concentration of NaOL, TA adsorbed on the fluorite surface and depressed the flotation of fluorite due to the preferential interaction between NaOL and Ca2+in the solution leading to a shortage in the effective NaOL in the solution. In the high concentration of NaOL, the adsorbed TA on the fluorite surface was displaced by the excessive NaOL in the solution; hence, the flotation of fluorite was recovered. In contrast, TA always hinders the interaction of NaOL with calcite regardless of the presence and absence of Ca2+and NaOL, hence, depressing the flotation of calcite. The study presented that a high concentration of NaOL may mitigate the negative effect of Ca2+on the fluorite surface and improve the separation of fluorite from calcite.Keywords:calcium ion;fluorite;adsorption mechanism;tannic acid
研究领域:
矿物学
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浮选化学
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DOI
高影响因子
MINERALS ENGINEERING
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2021
·
IF 4.765
Xun Wang,Jie Liu,Yimin Zhu,Yanjun Li
Cassiterite is the most purist tin-containing mineral and plays a dominative role in the tin resources. Owing to the limited selectivity of conventional collectors, the efficient separation of cassiterite from fluorite is normally difficult. Herein, 2-phosphonobutane-1,2,4-tricarboxylic acid (PBTCA) was employed as an eco-friendly depressant to selectively depress the flotation of fluorite. The flotation experiments were conducted to evaluate the separation efficiency of the two minerals, and the results showed that cassiterite and fluorite could be efficiently separated at the flotation reagent scheme of 15 mg/L PBTCA and 20 mg/L NaOL when pH was 8.04. Furthermore, a series of detection and simulation technologies including wettability analysis, zeta potential measurement, FTIR analysis, XPS analysis and DFT calculation were performed to uncover the underlying adsorption and depression mechanism of PBTCA on cassiterite and fluorite. These further analyses indicated that PBTCA could be chemisorbed on the fluorite surface through the interaction between the phosphate group in PBTCA and the calcium sites in fluorite. Moreover, the adsorption of PBTCA on fluorite surface would intensively inhibit the adsorption of NaOL. However, PBTCA was only weakly adsorbed on the cassiterite surface and could not affect the interaction between NaOL and cassiterite. Finally, a most likely adsorption model of PBTCA onto fluorite surface with the “mono-polar group” interaction was proposed by DFT calculations.
研究领域:
矿物加工工程
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表面化学
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产品关联
DOI
高影响因子
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
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产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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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
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2019
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IF 5.107
Guichen Gong,Pan Wang,Jie Liu,Yuexin Han,Yimin Zhu
The effect and mechanism of Cu(II) on the flotation separation of cassiterite from fluorite using styrene phosphonic acid (SPA) as a collector were investigated by flotation tests, zeta potential measurements, X-ray photoelectron spectroscopy (XPS) analysis and density function theory (DFT) calculations. SPA showed good collecting ability for both cassiterite and fluorite, and Cu(II) could intensively and selectively depress fluorite. At pH 4.0, using 100 mg/L SPA as the collector and 5 × 10 −4 mol/L Cu(II) as the inhibitor, a tin concentrate with a grade of 92.3% SnO 2 and a recovery of 85.6% was obtained for an artificially mixed sample which contained 47.86% SnO 2 . Zeta potential and XPS analyses indicated that Cu(II) was anchored on cassiterite surface but not on fluorite surface, and Cu(II) hindered the adsorption of SPA on fluorite but had negligible influence on the adsorption of SPA cassiterite. DFT calculations confirmed that the affinity between Cu(II) and SPA is much stronger than that between Cu(II) and fluorite surface, and the adsorption of SPA on cassiterite surface was not weakened by the presence of Cu(II). Consequently, it was inferred that Cu(II) consumed the collector SPA in the pulp, and the flotation of cassiterite was unaffected but fluorite was depressed by Cu(II). Therefore, Cu(II) is an effective inhibitor for the flotation separation of cassiterite from fluorite.
研究领域:
矿物加工工程
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表面化学
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计算化学
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DOI
高影响因子
MINERALS ENGINEERING
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2022
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IF 5.479
Long Wang,Weijian Lyu,Lingyun Huang,Fuping Li,Hao Zhang
The relatively similar physicochemical features and floatabilities of fluorite and barite in the flotation process make the separation of these two minerals rather difficult. Exploration and utilization of efficient depressants is vital to improve the flotation separation performance. In this study, gellan gum (GG) was adopted as the depressant in the flotation separation of fluorite and barite with sodium oleate (NaOL) as collector for the first time. The inhibitory impact of gellan gum on the flotation performances of these two minerals was evaluated via flotation tests. The potential inhibiting mechanism of GG was systematically revealed via series of surface analytical measurements. Flotation experiments indicated that GG exhibited strong depressing effect on the barite flotation, whilst it showed little impact on the fluorite flotation. Zeta potential tests and surface wettability analyses demonstrated that GG intensely adhered onto barite and strongly prevented the subsequent NaOL adsorption, while it barely affected the NaOL adsorption onto fluorite. Adsorption capacity measurements confirmed that much higher amount of GG adsorbed onto barite than fluorite. Fourier transform infrared (FTIR) spectroscopy analyses and X-ray photoelectron spectroscopy (XPS) results implied that the quite weak physisorption of GG on the fluorite surface occurred, whereas strong chemical adhesion of GG occurred between GG and barite, which resulted in completely disparate flotation behaviors of these two minerals. As a result, selectively depression of barite flotation and the flotation separation of fluorite from barite were achieved. Therefore, GG can be used as an efficient and eco-friendly depressant to realize the flotation separation of fluorite and barite.
研究领域:
矿物加工工程
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环境科学
✓ 已验证
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2020
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IF 5.774
Lu Ye,Yangcheng Lu
With the depletion of rich fluorite ore, flotation process suitable for fine-grained fluorite is of great necessity. In this study, such method was preliminarily developed with a combination of in-situ surface modification and gas-liquid microdispersion. By introducing additives into ball-milling, the interaction between reagents and particles was improved. Through exploitation of selective sedimentation of undesired minerals via pH adjustment, the flotation of fine-grained fluorite was achieved with little or even no depressant in this study. Using a well-designed membrane dispersion device, effective interaction between the particles and bubbles was achieved, with massive expansion of the surface area in a limited space, enabling continuous flotation in a miniaturized device. Satisfactory product grade and recovery were obtained while reducing the use of additives, along with significantly decreased costs related to energy consumption, wastewater and flue gas treatment, and facility investments. The mechanism of this flotation separation strategy was summarized on the basis of empirical data. The strategy was effectively and flexibly applied to fluorite ores with different particle sizes and surface properties.
研究领域:
矿物加工工程
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化学工程
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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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2023
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IF 5.2
Yongchao Miao,Shuming Wen,Zhenhao Guan,Qicheng Feng
In this study, the flotation tests revealed that ethylenediamine tetramethylenephosphonic acid (EDTMPA) as a calcite inhibitor has a stronger depression effect than EDTA (ethylene diamine tetraacetic acid) in the cassiterite flotation process, and the selective depression mechanism of EDTMPA was revealed by zeta potential test, TOC test, XPS analysis and DFT calculation . The flotation test results showed that effective separation of cassiterite and calcite could be achieved at pulp pH of 9.0, NaOL concentration of 1.80 × 10 −4 mol/L and EDTMPA concentration of 1.25 × 10 −5 mol/L. The selective adsorption of EDTMPA on the calcite surface was ascribed to the strong interactions between the phosphate ions in the former, and the surface Ca 2+ ions on the latter’s crystal lattice . DFT calculations also confirmed the strong affinity of EDTMPA for calcite and its weak affinity for cassiterite. The results of this study provide an experimental and theoretical background for the sustainable and eco-friendly separation of cassiterite from calcite.
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
危险品化学品经营许可证（带存储）