MINERALS ENGINEERING
·
2024
·
IF 4.9
Yiwen Hu,Jieliang Wang,Zhao Cao,Xu Wu,Wenda Lu,Weiwei Wang,Wenli Liu
Bastnaesite is an important strategic resource. Since the calcium-bearing gangue minerals in the pulp can dissolve and release Ca 2+ ions, Ca 2+ ions and sodium silicate have a co-depression effect on bastnaesite flotation, which will affect the separation and purification of bastnaesite. In this study, the mechanism of eliminating the co-depression effect using ethylene diamine tetraacetic acid (EDTA) was studied by micro-flotation, bench-scale flotation, zeta potential, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM)–energy spectrometry (EDS), contact angle and DFT calculations measurements. Micro-flotation results show that the addition of EDTA can effectively eliminated the co-depresses effect of Ca 2+ ions and sodium silicate. Bench-scale flotation tests showed that a high-quality rare earth (REE) ore concentrate with higher grade and recovery (62.35 % and 62.08 %, respectively) could be enriched by adding EDTA. Zeta potential results show that the combination of Ca 2+ ions and EDTA than with Ca 2+ ions alone, the surface potential of bastnaesite was significantly negative. XPS shows that EDTA prevented Ca-SiO 3 precipitation between Ca 2+ ions and sodium silicate by complexing Ca 2+ ions, which hindered the adsorption of sodium silicate to bastnaesite. SEM-EDS show that the addition of EDTA between Ca 2+ ions and sodium silicate, Ca 2+ ions had desorbed from the bastnaesite surface. Density functional theory (DFT) calculation showed that the adsorption energy of EDTA and Ca 2+ ions was much smaller than that of sodium silicate and Ca 2+ ions and Ca 2+ ions and mineral surface.
研究领域:
矿物学
·
浮选化学
✓ 已验证
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
SURFACE & COATINGS TECHNOLOGY
·
2022
·
IF 4.865
Zefei Zhang,Hao Chen,Yingqin Wang,Gang Wang,Lihong Li,Min Zhong,Hao Bai
Low melting point metals, such as copper, are often used as high-temperature cooling equipments and endure harsh environments during operations. This usually leads to reduced service life and reliability. To address this problem, a protective coating was prepared on copper via a slurry method. However, due to the low melting point of copper, solid-state sintering was applied. Therefore, during this process, the defects generated in the ceramic coating could affect the performance of the coating. To reduce the defects, a series of ceramic coating samples using sodium silicate water glass (SSWG) as the binder were prepared, changing the SSWG-to-aggregate mass ratio (SAMR) for each sample. The results showed that they were all related to the SAMR, and there was an optimal SAMR with minimum defects and favourable performance. The non-optimized SAMR lead to more internal defects, that is, microfractures and pores in the coating, resulting to a decline in the coating performance. By identifying the types of defects and quantifying them, the relationship between the SSWG and the generation of defects was studied, and the effect of the defects on the performance of the ceramic coating was analysed in detail. The research presented in this paper provides a method for the improvement of ceramic coatings by optimising the key factors that is the SAMR in solid-state sintering. The effect of thermal stress on the formation of microfracture defects during the sintering was investigated by experiments and simulation. It is found that with increase of sintering temperature , the thermal stress inside the coating increases gradually, resulting in more generation of microfracture defects inside the coating. The inhibition effect of SSWG on thermal stress during the sintering process was verified.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2024
·
IF 1.9
Zhanglei Zhu,Bohui Zhao,Jin Wang,Yiming Zhu,Qiuyue Sheng,Zhen Li,Ningning Zhang,Wei Yu
High-ash fine slime has an adverse effect on coal flotation. In this study, the roles of sodium silicate (SS) and sodium carbonate (SC) in the facilitating effect on lean coal flotation (a type of coking coal) were studied when sodium oleate (NaOL) was used as a collector through flotation tests, Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM-EDS) observations, turbidity measurements, and particle interaction energy calculations. The flotation tests found that SS has a stronger capacity than SC for the improvement of flotation performance of lean coal. Moreover, SEM-EDS observations and turbidity measurements showed that SS presents a stronger weakening effect for the coating of high-ash fine slime on the surface of low-ash coal particles than SC. Furthermore, the particle interaction energy calculations verified that the increase in the energy barrier for the attachment between low-ash coal particle and high-ash fine slime caused by SS is larger than SC, providing theoretical supports for the experiments. Compared to kerosene as a collector, based on the similar ash content, the yield of clean coal increases greatly with the synergistic effect of SS and NaOL. In summary, SS is an appropriate dispersant for lean coal flotation in sodium oleate system.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2013
·
IF 2.206
Xiaosheng Zhang,Weichao Sun,Huijuan Ma,Hong Xu,Jinxiang Dong
Layered sodium silicates β-Na2Si2O5 and kanemite were synthesized via facile methods under mild conditions. The tribological properties of β-Na2Si2O5 and kanemite utilized as additives in lithium grease were evaluated with a four-ball tester under different experimental conditions. The maximum nonseizure load value of 5.0 wt % β-Na2Si2O5 grease jumped from 353 N (the base grease) to 1568 N. However, 5.0 wt % MoS2 grease could only reach 617 N under the same conditions. The SEM and EDS results confirm that a protective film mainly composed of sodium silicates was formed on the worn surface during the friction process. The structural stability of β-Na2Si2O5 and kanemite after the wear test was studied by XRD. It was found that a loss of interlamellar water causes the layer structure of kanemite to collapse during a long-duration wear test. The layered structure of β-Na2Si2O5 is stable, and its tribological properties are better than those of kanemite.
研究领域:
材料科学
·
摩擦学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
·
IF 5.4
Wanting Yang,Zhuoyue Lan,Xiong Li,Yunchuan Li
The mechanism by which moraines influence the flotation process in high-altitude porphyry copper-molybdenum deposits was investigated. Micro-flotation experiments and tests using actual ore samples revealed that moraines significantly reduced the recovery and selectivity of copper-molybdenum ores. As the moraine content increased, the entrainment of gangue minerals also rose considerably. However, the addition of sodium silicate effectively mitigated this entrainment. At a sodium silicate dosage of 10 mg/L, copper recovery reached 90.42 % with a grade of 8.93 %, and gangue entrainment was reduced from 7.58 % to 4.01 %. Molybdenum recovery reached 96.56 % with a grade of 12.89 %, and the gangue entrainment rate decreased from 13.30 % to 1.93 %. Measurements of slurry rheology, viscosity, zeta potential, and slime coating tests further clarified that moraines affect the flotation of copper-molybdenum ores through a slime coating effect. At pH 4, moraine particles adhered to chalcopyrite and molybdenite surfaces, hindering effective collector-mineral interaction and reducing flotation efficiency. The addition of sodium silicate effectively mitigated both the mechanical entrainment and slime coating effects, promoting better separation of copper-molybdenum ores from moraines and improving the recovery and selectivity of target minerals. This study elucidates that the detrimental effects of moraine on the flotation of copper-molybdenum ores are predominantly attributed to entrainment and slime-coating phenomena. It further proposes an effective strategy to enhance the flotation efficiency of copper-molybdenum ores under moraine influence by incorporating sodium silicate.
研究领域:
矿物加工工程
·
地质学
✓ 已验证
DOI
高影响因子
TRIBOLOGY INTERNATIONAL
·
2011
·
IF 1.56
Zhaofeng Chen,Yajie Wang,Xiaosheng Zhang,Hong Xu,Jinxiang Dong
Two layered sodium silicate products were prepared using a new ion exchange method called the freezing titration ion exchange. The tribological properties of the ion exchange products as additives in mineral oil were evaluated using a four-ball tester. The products exhibited excellent friction behavior when used as additives in mineral oil. When 1 wt% was added, the tribological properties of the oils improved: the maximum non-seizure loads increased by over 27% and the wear scar diameter and friction coefficient decreased by over 50% and 25%, respectively. The friction and wear behaviors of the silicates were better than those of the typical lubricant additives .
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2017
·
IF 4.339
Song Wang,Pengfei Hao,Sanxi Li,Ailing Zhang,Yinyan Guan,Linnan Zhang
Several anhydrous silicates were prepared by calcination at 400 °C and utilized as solid base catalyst for synthesizing glycerol carbonate (GC) by transesterification of glycerol with dimethyl carbonate (DMC). Among them, calcined sodium silicate showed the best catalytic activity with glycerol conversion of 97.7%. Then, a series of sodium silicates calcined at different temperatures were characterized using TGA, Hammett indicator method, BET, XRD, FT-IR and FESEM. Effect of calcination temperature on their catalytic ability was carefully investigated, followed by a reaction optimization study. The basicity of sodium silicates calcined at different temperatures highly depended on calcination temperature; their catalytic ability was affected by their total basicity rather than by their BET surface area; and the increased amount of strong basic sites resulted in the formation of by-product which decreased the GC yield and GC selectivity. Sodium silicate calcined at 200 °C (Na 2 SiO 3 -200), which had the intermediate total basicity and relative low amount of strong basic sites, incurred the highest GC yield. The highest catalytic performance of Na 2 SiO 3 -200 was achieved under the condition that the 4:1 molar ratio of DMC to glycerol was reacted at 75 °C for 2.5 h. This catalyst could be reused five times without noticeable drop in catalytic activity.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
ECS Journal of Solid State Science and Technology
·
2020
·Vol. 9
·期 12
·123007
·
IF 2.142
Guodong Zhang,Jiaqi Chen,Yao Liu
Iron-based soft magnetic composites (SMCs) were prepared by two-step ball milling with sodium silicate and ferroferric oxide. The presence of the precoated silicate layer has increased the resistivity of the powder surface, which also improved the agglomeration of ferroferric oxide. The addition of magnetic ferroferric oxide improves the dilution effect. Combining the advantages of both sodium silicate and ferroferric oxide, the prepared soft magnetic composite material has excellent performance. After annealing at 400 °C, the core loss is 214.5 W Kg−1 (1 T, 1000 Hz), and the saturation magnetic induction is 1.33 T.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
Minerals
·
2024
·Vol. 14
·期 9
·870
·
IF 2.2
Jieliang Wang,Wenda Lu,Zhao Cao,Xu Wu,Peng Wang,Xiaoping Wang,Wenli Liu
The surface properties of bastnaesite and parisite are similar to their associated gangue mineral, fluorite, which makes the flotation separation of these two rare earth minerals from fluorite one of the industry’s most significant challenges. This study systematically investigates the inhibitory effects and mechanisms of sodium silicate (SS) on bastnaesite, parisite, and fluorite in an octyl hydroxamic acid (OHA) collector system through flotation experiments, various modern analytical methods, and DFT simulations. The flotation test results indicate that the inhibition effects of SS on the three minerals are in the order: fluorite > parisite > bastnaesite. Detection and analysis results indicate that SS forms hydrophilic complexes with Ca atoms on the surfaces of fluorite and parisite, enhancing surface hydrophilicity and inhibiting OHA adsorption, but its impact on bastnaesite is relatively minor. DFT simulation results show that OHA forms covalent bonds with metal ions on mineral surfaces, favoring five-membered hydroxamic-(O-O)-Ce/Ca complexes, and reacts more strongly with Ce atoms than Ca atoms. SS primarily forms covalent bonds with metal atoms on mineral surfaces via the SiO(OH)3−component, and OHA and SS compete for adsorption on the mineral surfaces. OHA has a stronger affinity for bastnaesite, whereas SS shows the highest affinity for fluorite, followed by parisite, and the weakest affinity for bastnaesite.
研究领域:
矿物加工工程
·
计算化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
·
2025
·
IF 2.7
Zengmou Li,Xiaoling Liu,Qianwen Wang,Xinyu Jiang,Rui Yan,Keyu Zhang,Yaochun Yao,Shaoze Zhang,Yin Li,Junxian Hu
Serious volume expansion for silicon-based material has extremely restricted its widespread application. Herein, Si@Na 2 SiO 3 composite with grape-liked structure was fabricated by a simple metal salt-assisted chemical etching method, which is enabled by the high corrosivity of NaHCO 3 . The gelatinous Na 2 SiO 3 can evenly coat the surface of Si nanoparticles, then efficiently inhibiting volume expansion. Meanwhile, porous structures etched by NaHCO 3 provide more diffusion channels for Li + . Si@Na 2 SiO 3 exhibits excellent cycling and rate properties: the discharge capacity of 1140.16mAh g −1 at 0.5 A g -1 after 100th cycling and the stable discharge capacity of 1565.64 mAh g −1 at 2.0 A g −1 . This research provides a simple and effective technology to exploit the high-capacity silicon-based anode material.
研究领域:
材料科学
·
电化学
✓ 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）