International Journal of Minerals Metallurgy and Materials
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2021
·Vol. 28
·期 6
·974-980
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IF 2.232
Guo Yun,Li Hong-yi,Yuan Yi-heng,Huang Jie,Diao Jiang,Li Gang,Xie Bing
The fusion of the leaching and purification processes was realized by directly using microemulsion as the leaching agent. The bis-(2-ethyhexyl) phosphoric acid (DEHPA)/ n -heptane/NaOH microemulsion system was established to directly leach vanadates from sodium-roasted vanadium slag. The effect of the leaching agent on the leaching efficiency was investigated, in addition to the molar ratio of H 2 O/NaDEHP ( W ), DEHPA concentration, solid/liquid ratio, stirring time, and leaching temperature. In optimal situations, the vanadium leaching efficiency reaches 79.57%. The X-ray diffraction characterization of the leaching residue and the Raman spectrum of the microemulsion before and after leaching demonstrate the successful entry of vanadates from the sodium-roasted vanadium slag into the microemulsion. The proposed method successfully realizes the leaching and purification of vanadates in one step, thereby greatly reducing production costs and environmental pollution. It also offers a new way to achieve the green recovery of valuable metals from solid resources.
研究领域:
冶金学
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环境科学
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DOI
高影响因子
Catalysts
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2022
·Vol. 12
·期 5
·549
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IF 4.501
Li Wang,Junbo Wang,Heping Cheng,Xiangxiang Zhou,Zhen Ma
A series of Ce1−xFexVO4(x = 0, 0.25, 0.50, 0.75, 1) catalysts prepared by modified hydrothermal synthesis were used for selective catalytic reduction (SCR) of NOxwith NH3. Among them, Ce0.5Fe0.5VO4showed the highest catalytic activity. The catalysts were characterized by X-ray diffraction (XRD), N2adsorption–desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray fluorescence (XRF), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction using H2(H2-TPR), and temperature-programmed desorption of NH3(NH3-TPD). The results indicated the formation of Ce-Fe-V-O solid solutions. The average oxidation states (AOS) of Ce, Fe, V, and O atoms changed obviously with the incorporation of Fe3+into CeVO4, and the acidity of Ce0.5Fe0.5VO4differs from that of CeVO4and FeVO4. The presence of more acid sites and a sharp increase in active oxygen species in Ce0.5Fe0.5VO4effectively improved the selective catalytic reduction (SCR) activity.Keywords:selective catalytic reduction;nitrogen oxides;cerium vanadate;iron vanadate;cerium-iron vanadate
研究领域:
环境科学
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催化化学
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DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
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2025
·Vol. 56
·期 3
·2541-2557
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IF 3.1
Cao Jianqi,Feng Shanshan,Wang Wanlin,Huang Daoyuan,Sun Yongqi
Vanadium, an extremely important metal element, is dominantly produced from the roasting–leaching process of vanadium–bearing slags, with the roasting process involving a conversion of vanadium–containing phases including iron–vanadium spinels and liquid phase into soluble vanadate. It is difficult to extract vanadium from iron–vanadium spinels due to their ultrastabilities and complex compositions. The presence of minor elements affects the stability of iron–vanadium spinels upon roasting as well as the further leaching process. In this study, the roles of various minor elements on phase and composition evolutions of iron–vanadium spinels upon calcium roasting were investigated by both advanced experimental characterizations (EPMA, XRD and XPS) and thermodynamic calculation using FactSage 8.3. The results first showed that the iron–vanadium spinel underwent a phase transition to form two distinct phases, namely a V-enriched phase and a Fe 2 O 3 solid solution. The presence of Cr 2 O 3 , MnO and MgO did not produce a new phase, but affected the compositions of the two phases formed. However, new phases were generated in the presence of TiO 2 and Al 2 O 3 , namely a Fe 2 TiO 5 phase and an Al-enriched phase, respectively. Moreover, a higher roasting temperature enhanced the partitioning of TiO 2 , Al 2 O 3 and Cr 2 O 3 from the V-enriched phase to the Fe 2 O 3 solid solution, which promoted the enrichment of V 2 O 5 into the V-enriched phase. A lower roasting temperature promoted the formation of manganese vanadate and magnesium vanadate for further leaching process. These findings offer a guidance for optimizing the roasting conditions for maximum vanadium extraction from iron–vanadium spinels.
研究领域:
冶金学
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材料科学
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DOI
高影响因子
STEEL RESEARCH INTERNATIONAL
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2022
·Vol. 93
·期 7
·2100788
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IF 2.126
Hongrui Yue,Gongjin Cheng,Jianxing Liu,Xiangxin Xue,Weijun Zhang
This study proposes a clean and effective routine and aims to solve the problems of material accumulation and hypoxia during roasting vanadium slag. The vanadium slag and CaO 2 powders are mixed, briquetted, and roasted at different parameters. The generated phases are Fe 2 O 3 , Fe–Mg oxides, Fe–Ti oxides, Ca 3 (VO 4 ) 2 , silicate, and SiO 2 after roasting. The solid reaction between V 2 O 5 and CaO is described using the vacancy diffusion mechanism. Ca 2+ (or V 5+ ) jumps and diffuses through the Ca 2+ (or V 5+ ) vacancies in the Ca 3 (VO 4 ) 2 layer and subsequently to the Ca 3 (VO 4 ) 2 /V 2 O 5 (or Ca 3 (VO 4 ) 2 /CaO) interface and reacts with V 2 O 5 (or CaO) and O 2 (decomposed from CaO 2 or transported from the air) to generate Ca 3 (VO 4 ) 2 . The vanadium leaching rate is very sensitive to the roasting parameters of CaO/V 2 O 5 molar ratio, temperature, time, and briquetting pressure. A maximum vanadium leaching rate of 98.31% is achieved with a CaO/V 2 O 5 molar ratio of 3/1, with temperature, time, and briquetting pressure being maintained at 900 °C, 50 min, and 10 MPa, respectively. The present routine, which greatly shortens the roasting time, can be realized through a rotary hearth furnace, and is likely to be accepted by both iron works and the environment due to its effective and clean characteristics.
研究领域:
冶金学
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环境工程
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DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
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2022
·Vol. 53
·期 4
·2227-2238
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IF 2.872
Yue Hong-Rui,Liu Jian-Xing,Cheng Gong-Jin,Xue Xiang-Xin,Zhang Wei-Jun
The material accumulation during roasting in the practical production causes the hypoxia of the internal materials, leading to the relatively lower vanadium recovery than that in theoretical studies. This work aims to solve the problem of material hypoxia through the Na 2 O 2 -briquetting roasting route. The vanadium slag and Na 2 O 2 powders were mixed, briquetted, and roasted at various parameters. The generated phases and their distributions were analyzed using X-ray diffraction, Fourier transform infrared spectroscopy, and electron probe microanalysis. The analyzing results showed that Fe 2 O 3 , Fe 3 O 4 , Mg 0.165 Mn 0.835 O, CaTiO 3 , and Na 3 VO 4 were generated during roasting. The solid–solid reaction between V 2 O 5 and Na 2 O was described using the vacancy-mediated diffusion mechanism. Na + (or V 5+ ), in the Na 2 O (or V 2 O 5 ) layer, jumped and diffused through the Na + (or V 5+ ) vacancies (in the Na 3 VO 4 layer) to the Na 3 VO 4 /V 2 O 5 (or Na 3 VO 4 /Na 2 O) interface. Na + (or V 5+ ) reacted with V 2 O 5 (or Na 2 O) and O 2 decomposed from Na 2 O 2 or transported from the air to generate Na 3 VO 4 . The roasted mixture was leached in an aqueous solution to study the effects of the roasting variables on the vanadium leaching recovery. The vanadium leaching recovery was very sensitive to the roasting variables, it showed very complicated relationships with the Na/V molar ratio, temperature, time, and briquetting pressure. The maximum vanadium leaching recovery of 95.57 pct was achieved when the Na/V molar ratio, temperature, time, and pressure were optimized as 3/1, 850 °C, 2.5 hours, and 5 MPa, respectively. The leaching solution containing vanadium was processed via precipitation and calcination to gather vanadium. The obtained compound was identified as V 2 O 5 with a purity of 96.84 pct, based on the high consistency of diffraction peaks between the present work and that of the joint committee on powder diffraction standards.
研究领域:
冶金学
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材料科学
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2025
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IF 9
Zeyu Chen,Bo Pang,Fujun Cui,Li Tian,Wanting Chen,Xuemei Wu,Xiaoming Yan,Gaohong He
High selective conduction of ion conductive membrane is essential to efficiency and cycling stability of vanadium redox flow battery, however, disentanglement of the trade-off between proton conductivity and vanadium ions permeability is challenging. In this work, the ortho-phenol side chain with vanadium ion recognition effect is proposed, which can effectively reduce vanadium ions permeability through coordinated chelation of vanadium ions. The ortho-phenol hydroxyl side chain, together with the sulfonic acid group, can also construct a microphase separation proton conductive channel to promote proton conduction. As the ion exchange capacity of ortho-phenol hydroxyl group (IEC OH ) in sulfonated polybenzimidazole reaches 2.89 mmol g −1 (SPBIOH-2.89), low area resistance (0.21 Ω cm 2 ) and vanadium ions permeability (1.71 × 10 −9 cm 2 s −1 ) are achieved. Accordingly, the H + /V n + selectivity presents 1.81 × 10 7 S s cm −3 , around 72.8 folds that of commercialized Nafion 212 membrane (2.49 × 10 5 S s cm −3 ). The VRFB assembled with SPBIPhOH-2.89 membrane presents excellent performance (energy efficiency 80.1 % at 200 mA cm −2 and discharge capacity decay rate 0.26 % per cycle at 100 mA cm −2 ), superior to that of Nafion 212 (66.7 % at 200 mA cm −2 , 0.71 % per cycle at 100 mA cm −2 ). The membrane performance is in top level compared with most reported amphoteric ion conductive membranes.
研究领域:
材料科学
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能源化学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
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2022
·Vol. 46
·期 13
·18465-18476
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IF 4.672
Yang You,Qingqing Hu,Fupeng He,Yongjie Liu,Qingyun Huang,Xuyang Liu,Zhixiong You,Xuewei Lv
Summary Ammonia gas (NH 3 ) is a clean energy, as well as an efficient reduction and nitridation agent. A novel process of reduction and nitridation with NH 3 followed by magnetic separation and low-temperature selective chlorination to deal with vanadium slag has been proposed. Vanadium spinel (V-Fe spinel, FeV 2 O 4 ) is the main V-bearing phase in vanadium slag, and its reduction and nitridation behavior with NH 3 were investigated in this study. Thermodynamic analysis indicated that the reaction was feasible. The experimental results demonstrated that NH 3 gas was an excellent reagent for reduction and nitridation. DFT calculation proved that NH 3 molecule was easier adsorbed on V atom. The phase component of the final product was Fe/Fe 4 N/VN x O y , whose relative mass fractions obtained by Rietveld refinement analysis were 23.5%, 1%, and 75.5%, respectively. The evolution of iron and vanadium was in the order FeV 2 O 4 → Fe 4 N/Fe 6 N 2−3 → Fe 4 N/Fe and FeV 2 O 4 → V 2 O 3 → VN x O y , respectively. VN x O y was a solid solution, whose O content decreased gradually as the temperature and duration time increased, whereas the N content increased correspondingly. The O content can be decreased to less than 0.10 wt.% after reduction and nitridation at 800°C to 850°C for 3 h.
研究领域:
冶金工程
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材料科学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2025
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IF 5.6
Yining Ma,Guangyao Sun,Xinyu Meng,Keyu Shi,Chenxu Ge,Di Wu,Shidong Ji,Xun Cao
The application of fluorescent powders to latent fingerprints development can enhance the contrast and minimize background interference, resulting in high-quality fingerprint images. In this study, two metavanadate phosphors, CsVO 3 and RbVO 3 , were successfully prepared via solid-state methods, and their fluorescence properties were investigated. When employed for latent fingerprints detection, both CsVO 3 and RbVO 3 exhibited well-defined and distinct papillary ridges of the fingerprint patterns with clear detailed features on various objects with different background interferences, including impermeable substrates, semipermeable materials as well as permeable paper. Additionally, the color of the visualized fingerprint images could be adjusted from yellow to green by changing the wavelength of ultraviolet light from 365 nm to 254 nm, demonstrating greater adaptability and flexibility of CsVO 3 and RbVO 3 . Overall, both powders exhibited remarkable sensitivity, selectivity, and contrast with minimal background interference, revealing the potential of CsVO 3 and RbVO 3 for latent fingerprints development.
研究领域:
法医学
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
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IF 8.6
Ling Yu,Hui Wang,Qi Huang,Hainan Liu,Qingkong Chen,Bojie Yuan,Qi Li,Xiaofei Zhao,Junwang Tang,Deqiang Zhao
A series of BiVO 4 /InVO 4 composites were synthesized by one-pot microwave method based on the ratio regulation of Bi/In. Consequently, the as-fabricated BiVO 4 /InVO 4 photocatalysts performed higher photocatalytic activities (100%) than pure InVO 4 and BiVO 4 . The prepared photocatalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), UV–vis diffuse reflection spectroscopy (UV–vis DRS) and Fourier transform infrared spectra (FTIR). The results indicate the formation of BiVO 4 /InVO 4 and it possesses enhanced solar light absorption. The enhanced reduction rate is ascribed to the efficient separation of photogenerated charge carriers due to the heterojunction formed between BiVO 4 and InVO 4 . The possible photocatalytic mechanism of BiVO 4 /InVO 4 composite was also discussed in detail.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
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IF 8.456
Shanshan Liu,Hao Wang,Ying Wei,Runduo Zhang,Sebastien Royer
ZrO2 supports, with diverse morphologies (hollow sphere, star, rod, mesoporous), were produced using hydrothermal and evaporation-induced self-assembly methods. Zirconia-supported vanadium oxide catalysts were prepared by wet impregnation and used for the low-temperature selective catalytic reduction (SCR) of NO with ammonia. Characterization of catalysts includes N2 physisorption, elementary analysis, X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, temperature-programmed reduction by H2, and temperature-programmed desorption of NH3. Significant differences in terms of activity are measured. 3 wt % V2O5 supported on mesoporous ZrO2 (V/MZ) presents excellent N2 yields (>90%, in the 200–400 °C interval), with a wide operating temperature window (NO conversion > 95%, in the 225–425 °C interval), and less interesting performances were obtained when vanadium oxide is supported over stars, hollow spheres, and rods. Surface characterization showed a content of tetravalent vanadium ion, when supported, decreasing in the order of mesoporous > hollow sphere > star > rod. This order is in perfect agreement with the order of performance of the catalyst in the NH3-SCR reaction. The impact of tetravalent ion’s presence on the surface is confirmed by diffuse reflectance infrared Fourier transform spectroscopy analysis, Brønsted acid sites generated on the surface, and the V4+-OH species involved in the reaction. The production of more important nitrite species over the tetragonal supported vanadium oxide catalyst could be another reason for the excellent NH3-SCR performance displayed by the V/MZ catalyst. When supported over monoclinic zirconia, like vanadium oxide over star-type morphology, the adsorbed NH3 species (NH4+ and coordinated NH3) reacted with NOx adsorption species (nitrate) to form ammonium nitrate. Ammonium nitrate can be decomposed to N2 and N2O (or NO2). Thus, NO conversion curves and N2 yield curves over tetragonal zirconia (MZ) at lower temperature were ahead of those over V/star ZrO2 because of the higher V4+ surface content and more active B acid sites associated with an easy formation of the nitrito intermediate.
研究领域:
催化化学
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环境科学
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材料科学
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DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 50
·76263-76274
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IF 5.19
Zhou Anhui,Qiu Zhaofu,Yang Ji,Yan Ruiqi
The all-vanadium redox flow battery (VRFB) is becoming a promising technology for large-scale energy storage due to its advantages such as scalability and flexibility. In recent years, the VRFB has been successfully developed and put into use in many countries. It is expected that the abandoned VRFB will generate a large amount of vanadium waste. To our knowledge, there are few reports on the disposal of spent VRFBs. Herein, chitosan-coated nano-zero-valent iron (CS-Fe 0 ) is proposed for the first time as adsorbents for the treatment of spent VRFBs. It can provide a new approach to deal with the upcoming large number of spent VRFBs. The calculated maximum adsorption capacity for V(V) of chitosan and CS-Fe 0 reached 209.5 and 511.3 mg/g at 288 K, respectively. CS-Fe 0 showed better adsorption performance than chitosan under different pH conditions and is easy to be separated from the liquid phase. The Freundlich isotherm was suitable for the adsorption process of chitosan, and CS-Fe 0 was more consistent with the Langmuir isotherm. Ionic strength (0.05–0.5 M) had a positive effect on the adsorption capacity of CS-Fe 0 , and the influence of coexisting anions on CS-Fe 0 could be negligible. FTIR and XPS analyses revealed that the primary mechanisms were the electrostatic attraction of chitosan and redox of Fe 0 . The present study confirmed that CS-Fe 0 could be a potential material to efficiently trap V(V) from the VRFB electrolyte.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Qiuping Li,Shaopeng Gu,Liang Yu,Funian Han,Jingmeng Dong,Chunmei Li,Jiaqi Jia
An effective and environment-friendly method for preparing NaVO 2 , which can be used as an energy storage material, from Na 2 CO 3 roasted vanadium-chromium slag was proposed using water as the leaching medium. Vanadium-chromium slag with 30 % Na 2 CO 3 was heated in air and argon atmospheres from 30 °C to 1000 °C, respectively. The results show that vanadium compounds converted to NaVO 3 while chromium compounds to Na 2 CrO 4 under air. NaVO 3 and Na 2 CrO 4 were water-soluble making the separation of vanadium and chromium complicated. NaVO 3 and Na 2 CrO 4 were water-soluble making the separation of vanadium and chromium complicated. Heating vanadium-chromium slag in an argon atmosphere caused Fe 2 VO 4 to react with Na 2 CO 3 , forming NaVO 2 and NaFeO 2 below 1000 °C. However, chromium compounds unreacted in argon. NaFeO 2 was insoluble, while NaVO 2 was water-soluble with a leaching efficiency exceeding 70 %. Notably, the characteristic peak of V(III) in NaVO 2 was first found to be −532.00 ppm by the liquid 51 V NMR spectrum. This method represents a novel, green strategy for the resource utilization of vanadium-chromium slag, involving Na 2 CO 3 roasting in an argon atmosphere to produce NaVO 2 . It offers a promising approach to reduce the cost of NaVO 2 battery production and support its commercialization.
研究领域:
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
危险品化学品经营许可证（带存储）