International Journal of Electrochemical Science
·
2023
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IF 1.5
Hua Feng,Min Hu,Qunying Xu,Zhongwei Zhang,Yongning Wu
Currently, a large amount of harmful heavy metals is discharged into the soil environment, which will eventually affect the quality of food and harm human health through the food chain. Therefore, it is of great theoretical and practical significance to establish an analytical method for the determination of trace heavy metals in food. In this paper, a differential pulse stripping voltammetric method for the determination of chromium in food was established, and the sample was pretreated with a wet digestion method suitable for rapid detection in the field. Finally, this HNO 3 -H 2 O 2 wet digestion electrochemical determination method was evaluated.
研究领域:
分析化学
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环境科学
·
食品安全
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Qiuping Li,Shaopeng Gu,Liang Yu,Funian Han,Jingmeng Dong
A method to separate vanadium (V) and chromium (Cr) from vanadium-chromium (V-Cr) slag was developed to treat the hazardous substances effectively. This approach was achieved by heating V-Cr slag with Na 2 CO 3 in air within a temperature range of 30 °C to 1400 °C. Through TG-DSC, XRD, SEM-EDS and XPS tests, the results showed that Na 2 CO 3 reacted with V compounds at lower temperatures, producing NaVO 2 and Na 3 VO 4 . At the high-temperature stage, Na 2 CO 3 reacted with Cr compounds, resulting in Na 2 CrO 4 and Cr 2 O 3 formation on the slag surface. As the temperature exceeded 1200 °C, volatiles (Na 2 CrO 4 , NaCrO 2 , and other Cr compounds) were generated from the residuals and collected by condensation to separate V and Cr. This method provides a novel strategy for eco-friendly resource utilization of V-Cr slag, which is highly efficient, minimizes hazardous wastes, and can be further promoted in the industry.
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
Science China-Chemistry
·
2025
·
IF 9.7
Wu Min,Nan Mingjun,Liu Shumin,Zhong Caihe,Qiao Lin,Zhang Huamin,Ma Xiangkun
With the increasing demand for energy storage technology, iron-chromium flow batteries (ICFBs) have been widely concerned because of their price advantage. However, the low electrochemical activity of Cr 3+ /Cr 2+ redox couples and the side hydrogen evolution reaction limit the industrial application of ICFBs. A multi-dimensional Bi/carbon composite electrocatalyst (Bi@C) for ICFB is designed and prepared to improve the electrochemical activity of Cr 3+ /Cr 2+ redox couples. Benefiting by using the Bimetal organic framework (Bi-MOF) with solid matrix as precursors, Bi nanospheres are highly dispersed on the Bi@C electrocatalyst that effectively enhances the electrochemical activity. The special morphology of Bi@C electrocatalyst helps the transfer of electrons and ions, significantly reducing the polarization of battery. Herein, the 3D porous carbon frames accelerate mass transfer, and the 2D carbon nanobelts and carbon layer coating on 0D Bi nanospheres improve the conductivity of Bi nanospheres. Therefore, the ICFB with multi-dimensional Bi@C electrocatalyst exhibits coulombic efficiency of 98.10% and energy efficiency of 79.14% at 140 mA cm −2 , which is higher than ICFBs with commercial graphite carbon electrocatalyst and with heat treatment carbon felt. This work provides a simple and economical method to fabricate a high-performance multidimensional Bi@C electrocatalyst for Cr 3+ /Cr 2+ redox couples, boosting the development of ICFBs.
研究领域:
能源材料
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电化学
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DOI
高影响因子
METALS AND MATERIALS INTERNATIONAL
·
2021
·Vol. 27
·期 12
·5389-5398
·
IF 3.642
Hong S. F.,Lu Z. C.,Liu Y. H.,He Q. M.,Jiang W.,Zeng M. Q.
Abstract Supersaturated solid–solutions in a W–Cr alloy system were fabricated by conventional milling and plasma milling. The different extension mechanisms of the solid solubility that were created by ball milling with and without discharge plasma were studied. The solid–solubility of Cr in W for the P-milling W–Cr alloy system was higher, which indicates that plasma milling promotes the formation of W(Cr) solid–solution more easily than conventional milling. According to Miedema’s model, in the W–Cr alloy system, the free-energy change to form a W(Cr) solid solution by plasma milling is reduced compared with conventional milling because of the heating effect of the discharge plasma. Therefore, a higher stored energy in the grain boundaries and dislocations of the W–Cr nanograins during plasma milling makes it easier to overcome the thermodynamic barrier in the formation of a solid–solution, when compared with conventional milling. Graphic Abstract
研究领域:
材料科学
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物理学
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DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
·
2024
·Vol. 55
·期 6
·4775-4786
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IF 2.4
Luo Shuxuan,Ma Xingyue,Wang Wanlin,Zhang Lei,Sun Yongqi
The rapid advancement in stainless steel manufacturing has resulted in the substantial accumulation of stainless steel slags. In those slags, a significant proportion of trivalent chromium is susceptible to oxidation, forming highly toxic hexavalent chromium, particularly under oxidizing atmosphere. Therefore, prior to landfilling or resource recycling, specialized modification of phase transitions is essential. This study is based on the strategy of converting chromium into spinel structure to achieve detoxification. Initially, the thermodynamic calculations were conducted to analyze the formation and transformation behaviors of spinels in an alkaline environment, with particular emphasis on changes in the valence states of manganese. The synthesis and investigation of typical Mg 1− x Mn x Cr 2 O 4 spinels commonly encountered in stainless steel slags treatment process were subsequently conducted. Through various characterization techniques and leaching tests, it was found that the stability of Mn 2+ incorporated MgCr 2 O 4 was diminished. However, with an increase in MnO content from 5 to 20 pct (in mole), the stability of Mg 1− x Mn x Cr 2 O 4 spinels showed an upward trend, though remaining lower than that of pure MgCr 2 O 4 . The subsequent introduction of CaO for high-temperature calcination revealed that the disruption of tetrahedral sites in the spinels primarily originates from Mn 2+ , whereas Mg 2+ exhibited a greater stability in occupying tetrahedral sites. A comprehensive understanding of the properties of Mg 1− x Mn x Cr 2 O 4 spinels could contribute to the target modification and application of stainless steel slags.
研究领域:
材料科学
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环境工程
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化学工程
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冶金学
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DOI
高影响因子
ENVIRONMENTAL POLLUTION
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2020
·
IF 6.793
Tianhao Tang,Xiaochun Liu,Longqian Wang,Achuo Anitta Zuh,Weichuan Qiao,Jun Huang
Bioaccumulation and toxicity of per-and polyfluoroalkyl substances and metal in plants have been confirmed, however their contamination in soil and plants still requires extensive investigation. In this study the combined effects of chlorinated polyfluoroalkyl ether potassium sulfonate (F53B) and chromium (Cr) on water spinach ( Ipomoea aquatica Forsk ) were investigated. Compared with each single stress, the combination of F53B and Cr (VI) reduced the biomass and height and increasingly accumulated in the roots and destroyed the cell structure. Besides, the co-contamination led to the immobilization of F53B and Cr (VI) in soil, which affected their migration in soil and transfer to plants. The antioxidant response and photosynthesis of the plant weakened under the single Cr (VI) and enhanced under the single F53B treatment; however the contamination of F53B and Cr (VI) could also reduce this effect, as confirmed by the gene expression of MTa, psbA and psbcL genes. This study provides an evidence of the environmental risks resulting from the coexistence of F53B and Cr (VI).
研究领域:
环境科学
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植物学
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Yongchao Wang,Yahui Liu,Fancheng Meng,Jian Zhang,Shuai Zhao,Xile Tian,Lina Wang,Desheng Chen,Tao Qi
The significant chemical similarity between vanadium and chromium complicates the process of efficient extracting V(Ⅳ) from the solution containing Cr(Ⅲ) to prepare high-purity vanadyl sulfate electrolyte. In this study, the separation of vanadium and chromium with 2-ethylhexyl phosphoric acid-2-ethylhexyl ester (EHEHPA) was enhanced by increasing the concentration of SO 4 2− . Under the extraction equilibrium pH of 2.5, the extraction of Cr(III) was suppressed by increasing the concentration of SO 4 2− anions, which hardly affected the extraction efficiency of V(IV), achieving a separation factor as high as 5780.6 at SO 4 2− concentration of 1.75 mol·L −1 . Furthermore, after pretreatment of the water-leaching solution of sodium-roasted vanadium slag, extraction was carried out under the conditions of equilibrium pH of 1.8 and SO 4 2− concentration of about 2.00 mol·L −1 , and after stripping, the vanadyl sulfate electrolyte containing 2.12 mol·L −1 of vanadium and only 0.11 mg·L −1 of chromium was obtained. It was proved that Cr(Ⅲ) mainly extracted in the form of CrSO 4 + into organic phase by one EHEHPA dimer as [CrSO 4 (H 2 O)] + under higher SO 4 2− concentrations (e.g., ≥1.50 mol·L −1 ), while Cr(Ⅲ) was extracted by two EHEHPA dimers as Cr 3+ without SO 4 2− in the solution. Based on the density functional theory, the complex structures of Cr(III) were optimized and the energy changes of Cr(III) extraction reactions were calculated, indicating the complexation between SO 4 2− and Cr(III) under higher SO 4 2− concentrations resulting in the inhibition of Cr(III) extraction, and thus enhancing the separation of vanadium and chromium.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 9
·2103
·
IF 3.1
Pengfei Zhu,Qiaosen Yuan,Na Li,Zhaoxia Hu,Shouwen Chen
The development of efficient catalysts with longevity to remove chlorobenzene is challenging due to Cl poisoning. Herein, a series of Mn-Cr/ZrOxcatalysts supported by Zr-based metal-organic framework (UiO-66)-derived ZrOxwas prepared and investigated for chlorobenzene (CB) catalytic oxidation. MnCr/ZrOx-M prepared via a wet impregnation method presented an amorphous structure, indicating the homogeneous dispersion of Cr and Mn, which improved acid and redox properties. 40Mn7Cr3/ZrOx-M exhibited the best catalytic activity for chlorobenzene oxidation with T90of 293 °C, which is mainly due to the strong interaction between manganese and chromium promoted by the large specific surface area of the ZrOxsupport. Furthermore, 40Mn7Cr3/ZrOx-M presented excellent stability for chlorobenzene oxidation.
研究领域:
环境科学
·
催化化学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Yun Guo,Hong-Yi Li,Jie Cheng,Shuo Shen,Jiang Diao,Bing Xie
The V-Cr-bearing reducing slag (VCBRS) is solid waste, which cannot be treated at present. This work proposes an effective approach to separately recover its major elements of V, Cr and Si and fully utilize the VCBRS with added-values. Flocculation desiliconization is used to extract Si from the acid solving liquid of VCBRS and Si is recovered as white carbon black with purity of 94.60% and recovery of 93.04%. After desiliconization, V in the solving liquid is selectively oxidized by H 2 O 2 and extracted by microemulsion extraction, which is recovered as V 2 O 5 whose purity is 99.60% with recovery at 96.32% from the stripping liquor of loaded microemulsion . Cr in the raffinate is recovered by alkaline precipitation as final product of Cr 2 O 3 with purity of 98.83% and recovery of 92.68%. The principles are discussed in detail and the operation conditions are optimized systematically. The microemulsion and wastewater are both cyclically utilized, which eliminates the secondary wastes. This work efficiently recovers all valuable elements with increased values from the solid waste, which can not only solve the environmental pollution problem, but also realize the efficient recovery of valuable elements to achieve comprehensive utilization.
研究领域:
冶金工程
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环境科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Fenglei Liu,Anjie Wang,Miao Xiang,Qingyuan Hu,Baowei Hu
Herein, a magnetic amine-functionalized mesoporous silica SBA-15 (Fe 3 O 4 @SBA-15-PDA/HBP-NH 2 ) adsorbent was fabricated by loading Fe 3 O 4 nano-particles on amino-terminated hyperbranched polymers (HBP-NH 2 ) functionalized SBA-15 and exploited for chromium (VI) and uranium (VI) elimination. The morphologies and microstructures of as-obtained materials were observed using different physicochemical and spectroscopic techniques. Meanwhile, batch experiments were performed to investigate the impacts of various water environment conditions on removal process including solution pH, equilibrium time and temperatures. The maximum adsorption capacities of U(VI) and Cr(VI) on Fe 3 O 4 @SBA-15-PDA/HBP-NH 2 reached up to 77.4 mg/g and 66.5 mg/g under optimal water environment conditions. Moreover, the characterization analysis manifested that removal of U(VI) was fulfilled through the surface complexation with amino and phenolic hydroxyl groups, while Cr(VI) were firstly electrostatically adsorbed, and subsequently reduced to less toxic Cr(III) by phenolic hydroxyl groups. These findings demonstrated that this new magnetic amine-functionalized SBA-15 could be considered as valuable materials in environmental cleanup.
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
Polymers
·
2020
·Vol. 12
·期 3
·714
·
IF 3.426
Lili Ren,Zhihui Yang,Lei Huang,Yingjie He,Haiying Wang,Liyuan Zhang
Here, a nanofiber-exfoliated bacteria cellulose aerogel with improved water affinity and high mass transfer was synthesized. Consequently, poly Schiff base can be uniformly coated within the body of bacteria cellulose aerogel without the traditional dispersion treatment. The composite aerogel has adequate mechanical and thermal stability and high mass transfer efficiency. Such an aerogel can serve as a superior adsorbent for flow through adsorption of pollution. Typically, the adsorption capacity towards Cr(VI), Cu(II), Re(VII), Conga red, and Orange G reaches as high as 321.5, 256.4, 153.8, 333.3, and 370.3 mg g−1, respectively. Moreover, the adsorption by this composite aerogel is very fast, such that, for example, at just 2 s, the adsorption is almost finished with Cr(VI) adsorption. Moreover, the composite aerogel exhibits a good adsorption-desorption capability. This research will hopefully shed light on the preparation of bacteria cellulose-derived macroscopic materials powerful in not only environmental areas, but also other related applications.Keywords:bacteria cellulose;poly Schiff base;chromium;adsorption
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Fenglei Liu,Shan Hua,Chao Wang,Baowei Hu
Herein, using dialdehyde waste paper (DAWP) as a cross-linking agent to immobilize persimmon tannin (PT) was first used to remove the U(VI) and Cr(VI) via the “waste control by waste” concept. The microscopic and macroscopic surface properties of the as-prepared adsorbent was characterized by the advanced characterization techniques. Factors that affected the elimination process such as variable pH, coexistence ions and equilibrium time were investigated by batch techniques. The results showed that the maximal removal capacities of U(VI) and Cr(VI) on DAWP-PT were 242.3 mg/g (pH = 6.0) and 178.7 mg/g (pH = 2.0) at 298 K, which exhibited competitiveness with most of the reported solid materials. Meanwhile, adsorption data were fitted perfectly to the Langmuir and Pseudo-second-order equations, which indicated that the monolayer and homogenous chemisorption dominated the removal process. The SEM-EDX, DFT and XPS analysis conformed that adsorption of U(VI) was mainly via surface complexation, while the elimination of Cr(VI) was a redox reaction process, and about 65.33% of Cr(III) and 34.67% of Cr(VI) co-existed onto the surface of DAWP-PT. Thus, this study would provide a high-efficiency and low-cost adsorbent for radionuclide and heavy metal treatment.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）