Frontiers of Environmental Science & Engineering
·
2021
·Vol. 15
·期 6
·1-12
·
IF 4.357
Meng Fanling,Xia Yunxue,Zhang Jianshuai,Qiu Dong,Chu Yaozhu,Tang Yuanyuan
Chromium slag usually contains various heavy metals, making its safe treatment difficult. Glass-ceramic sintering has been applied to resolve this issue and emerged as an effective method for metal immobilization by incorporating heavy metals into stable crystal structures. Currently, there is limited knowledge about the reaction pathways adopted by multiple heavy metals and the co-stabilization functions of the crystal structure. To study the Cu/Cr co-stabilization mechanisms during thermal treatment, a simulated system was prepared using a mixture with a molar ratio of Al 2 O 3 :Fe 2 O 3 :Cr 2 O 3 : CuO = 1:1:1:3. The samples were sintered at temperatures 600–1300°C followed by intensive analysis of phase constitutions and microstructure development. A spinel phase (CuFe x Al y Cr 2− x − y O 4 ) started to generate at 700°C and the incorporation of Cu/Cr into the spinel largely complete at 900°C, although the spinel peak intensity continued increasing slightly at temperatures above 900°C. Fe 2 O 3 /Cr 2 O 3 was more easily incorporated into the spinel at lower temperatures, while more Al 2 O 3 was gradually incorporated into the spinel at higher temperatures. Additionally, sintered sample microstructures became more condensed and smoother with increased sintering temperature. Cu / Cr leachability substantially decreased after Cu/Cr incorporation into the spinel phase at elevated temperatures. At 600°C, the leached ratios for Cu and Cr were 6.28% and 0.65%, respectively. When sintering temperature was increased to 1300°C, the leached ratios for all metal components in the system were below 0.2%. This study proposes a sustainable method for managing Cu/Cr co-exist slag at reasonable temperatures.
研究领域:
环境科学
·
材料科学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2017
·Vol. 35
·期 2
·203-208
·
IF 1.852
Hongxia Qin,Yingying Bian,Yaxi Zhang,Longfei Liu,Zhenfeng Bian
In this paper, the process of photocatalytic reduction of hexavalent chromium was investigated over Ti 3+ -modified TiO 2 photocatalysts. The Ti 3+ surface defects were repaired by annealing as-prepared sample at different temperatures to control the amount of Ti 3+ sites. The samples were characterized by SEM, XRD, BET, UV–vis absorption, EPR and XPS. The results showed Ti 3+ defects were successfully doped in TiO 2 . The surface selective adsorption of hexavalent chromium [Cr 2 O 7 2 − (Cr(VI))] and the desorption of trivalent chromium [Cr 3+ (Cr(III))] were investigated during the process of photocatalytic reduction. Zeta potential results presented that the increased positive charges due to more Ti 3+ defects on the surface show a significant improvement for adsorption of Cr(VI). Accordingly, the surface positive charges controlled by the Ti 3+ defects play important roles in the photocatalytic reduction of Cr(VI).
研究领域:
环境化学
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材料科学
·
光催化
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表面科学
·
环境污染治理
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Ningyi Chen,Shuang Wu,Ying Xu,Sijie Lv,Xianhua Wang,Qingrui Zhang,Bingjun Pan
High-resolution identification of chromium (Cr) species, especially various organic-Cr complexes, in a convenient and economically-feasible manner is the prerequisite for achieving the advanced treatment of chromium wastewater. To this end, a colorimetric nano-Au sensor array was developed by taking advantage of the UV-spectra shift of gold nanoparticles (Au NPs) upon interaction with Cr species; specifically, four molecular modifiers [i.e., iminodiacetic acid (IDA), tripolyphosphate (TPP), cetyltrimethylammonium bromide (CTAB), and 1,5-diphenylcarbazide (DPC)] were intentionally employed for assembling nano-Au array receptors, which showed respective responses toward different Cr species through the formation of coordination, hydrophobic interaction, electrostatic attraction, and redox reaction , respectively; the “fingerprint” differences of the unique optical properties were then integrated for semi-quantitatively recognizing Cr species by pattern recognition techniques. Eleven ubiquitous Cr species [i.e., Cr(III), Cr(VI), and various Cr(III)-organic complexes] served as the model samples, which could be sensitively identified, no matter in individual or mixture mode, by the developed nano-Au sensor array on the basis of the colorimetric responses resulted from diverse nano-Au-aggregation behaviors, with excellent anti-interference ability in the simulated or actual water scenario. Attractively, the nano-Au sensor array can achieve very sensitive detection limit of the quantitative analyses of Cr species in a prompt in-situ manner, which usually requires a two-step process of separation and detection for the conventional analytical methods. Such a convenient strategy of Cr species discrimination conduces to rationally designing specific protocols for the advanced treatment of chromium wastewater.
研究领域:
环境科学
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分析化学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Shitong Yang,You Wu,Shiying Bi,Xinghua Xu,Wenyu Wu,Yongsheng Wang
The structure–function relationship of ion-imprinted polymers for toxic hexavalent chromium (Cr(VI)) is poorly understood. In this study, a series of Cr(VI)-imprinted chitosan (CS)-sodium tripolyphosphate (STPP) composites were prepared by sol–gel method using different alkali/acid combinations and drying modes. The elution of CS-STPP polymer with 1 M NaOH+5 mM HNO 3 followed by freeze drying produced the optimal IIP-B+5A-fd material. The distinct structural stabilities and surface charges of imprinted CS-STPP composite determined their disparate Cr(VI) sorption abilities. The Cr(VI) sorption ratio on IIP-B+5A-fd kept higher than 97 % at pH<7, while that on non-imprinted NIP-B+5A-fd decreased from ∼ 73 % to ∼ 28 % as the solution pH rose from 4 to 7. The Cr(VI) sorption kinetics on IIP-B+5A-fd reached equilibrium after 12 h, faster than 24 h on NIP-B+5A-fd. The maximum Cr(VI) sorption capacity of IIP-B+5A-fd (41.29 mg/g) surpassed those of NIP-B+5A-fd (26.00 mg/g) and various previously reported adsorbents. IIP-B+5A-fd exhibited a much better Cr(VI) sorption efficiency (∼83 %) than NIP-B+5A-fd (∼20 %) in the presence of mixed aqueous components. The Cr(VI) sorption mechanism on IIP-B+5A-fd was electrostatic attraction–redox–inner-sphere complexation. Overall, the prepared IIP-B+5A-fd polymer holds a promising potential for highly efficient and selective removal of Cr(VI) from a polluted water environment.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Yongzheng Jia,Yu Qing,Baoyan Feng,Yiwei Zhong,Lei Dai,Mingyong Wang
Green separation and efficient extraction of vanadium and chromium from vanadium-chromium leaching solution are serious challenges for the utilization of chrome-vanadium slag. A green sucrose reduction-H 2 O 2 selective oxidation route is proposed for deep separation of vanadium and chromium from vanadium-chromium leaching solution based on different redox properties. Eh-pH diagram of V-Cr-H 2 O system and existence forms of vanadium and chromium ions are calculated. Obvious difference of redox properties between V(V) and Cr(VI) exists in acidic environment. The dependences of selective separation on pH for reduction, temperature, m (sucrose) /m (Cr(VI)) and n (H2O2) /n (V(V)) are studied. The concentration ratio of vanadium to chromium in solution after selective separation of chromium decreases from 1.6 to 0.06. The extraction ratios of Cr 2 O 3 and V 2 O 5 are 96.3% and 93.8%, respectively. The redox behavior of V(V) and Cr(VI) is revealed. Cr(VI) and V(V) are reduced to Cr(Ⅲ) and V(IV) by 5-hydroxymethylfurfural, a hydrolysate of sucrose, and then V(IV) is selectively oxidized to V(V) by H 2 O 2 . Cr 2 O 3 ·n(H 2 O) and ammonium polyvanadate obtained by hydrolysis and ammonium precipitation are calcined to Cr 2 O 3 and V 2 O 5 , respectively. Cr 2 O 3 with the purity of 99.4% can be used as high-quality pigment. The purity of V 2 O 5 meets the requirements of YB/T 5304–2011 for 98 V 2 O 5 .
研究领域:
冶金工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF TRACE ELEMENTS IN MEDICINE AND BIOLOGY
·
2014
·
IF 2.491
Hai-yan Tang,Qing-gui Xiao,Hong-bin Xu,Yi Zhang
The hypoglycemic activity of chromium methionine (CrMet) in alloxan-induced diabetic (AID) mice was investigated and compared with those of chromium trichloride hexahydrate (CrCl 3 ·6H 2 O) and chromium nicotinate (CrNic) through a 15-day feeding experiment. The acute oral toxicity of CrMet was also investigated in ICR (Institute for Cancer Research) mice by a single oral gavage. The anti-diabetic activity of CrMet was explored in detail from the aspects of body weight (BW), blood glucose, triglyceride, total cholesterol, liver glycogen levels, aspartate transaminase (AST) and alanine transaminase (ALT) levels. The obtained results showed that CrMet had beneficial effects on glucose and lipid metabolism, and might possess hepatoprotective efficacy for diabetes. Daily treatment with 500 and 1000 μg Cr/kg BW of CrMet in AID mice for 15 days indicated that this low-molecular-weight organic chromium complex had better bioavailability and more beneficial effects on diabetics than CrCl 3 ·6H 2 O. CrMet also had advantage over CrNic in the control of AST and ALT activities. Acute toxicity studies revealed that CrMet had low toxicity potential and relatively high safety margins in mice with the LD 50 value higher than 10.0 g/kg BW. These findings suggest that CrMet might be of potential value in the therapy and protection of diabetes.
研究领域:
药理学
·
毒理学
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内分泌学
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营养科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Zhuan-nian Liu,A.-ping Fan,Xiao-gang Han,Habiba Shapour,Qing-yun Zhang
The chelating adsorbent PEI-MIL-101(Cr) was prepared by introducing polyethyleneimine (PEI) into the MIL-101(Cr) channel in this paper. X-ray diffractometer, Fourier transform infrared spectrometer and scanning electron microscope were applied to characterize the structure and morphology of MIL-101(Cr) and PEI-MIL-101(Cr). The adsorption properties and mechanism of the MIL-101(Cr) and PEI-MIL-101(Cr) to Cr(VI) were studied. The results showed that adsorption capacity of PEI-MIL-101(Cr) for Cr(VI) was obviously better than MIL-101(Cr). The adsorption isotherm of Cr(VI) onto MIL-101(Cr) and PEI-MIL-101(Cr) can be described by Langmuir model. The maximum adsorption amount for Cr(VI) onto MIL-101(Cr) and 30% PEI-MIL-101(Cr) was 61.99 and 40.34 mg/g. The adsorption kinetic data of the two adsorbents followed the pseudo second-order model. The negative values ΔH and ΔG illustrate that the process is spontaneous and exothermic. PEI-MIL-101(Cr) can be reused for four times.
研究领域:
环境化学
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材料科学
·
污染控制
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吸附技术
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功能材料
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水污染治理
✓ 已验证
DOI
高影响因子
JOURNAL OF SUPERCRITICAL FLUIDS
·
2022
·
IF 4.514
Jianqiao Yang,Jiyuan Sun,Shuyuan Bai,Hao Wu,Shuzhong Wang,Yanhui Li,Wenhao Ma,Donghai Xu
To improve the corrosion resistance of component materials in supercritical water oxidation (SCWO) environment, a 15 µm Cr coating was prepared on Alloy 625 by magnetron sputtering, and the effect of oxygen concentration (0 M, 0.16 M, and 0.94 M) on the stability of the Cr coating in an SCW environment was investigated. Results show that the stability of the Cr 2 O 3 layer strongly depends on the oxygen concentration in the exposure environment. The protective Cr 2 O 3 layer was transformed to soluble Cr(VI) species and dissolved in SCW containing 0.94 M oxygen. Except for Cr 2 O 3 , some Fe/Ni containing oxides were also detected. The stability of the Cr coating in SCW with different concentrations of oxygen is discussed.
研究领域:
材料科学
·
腐蚀与防护
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表面工程
·
能源环境工程
·
高温化学
✓ 已验证
DOI
高影响因子
Green Energy and Intelligent Transportation
·
2025
·
IF 16.4
Yingchun Niu,Wenjie Lv,Yinping Liu,Ziyu Liu,Ruichen Zhou,Xuan Zhou,Weiwei Guo,Wei Qiu,Chunming Xu,Quan Xu
The performance of iron-chromium redox flow batteries is significantly influenced by the electrochemical activity of chromium and iron ions, with a particular emphasis on the reactivity of chromium. However, the impact of the chemical properties of chromium ions on the efficiency of electrochemical reactions remains largely unexplored. In this study, In this study, we introduced PbCl 2 into the electrolyte and achieved in-situ electrodeposition of the lead-based catalyst. Our findings indicate that the incorporation of lead ions effectively enhances the chromium half-reaction while inhibiting hydrogen evolution. Experimental analyses and molecular dynamics simulations reveal that PbCl 2 does not significantly affect the electrochemical performance of the electrolyte, its influence is mainly due to the electrochemical deposition on the electrode surface. The observed performance improvement is ascribed to the combined effects of Pb and Pb(ClO 3 ) 2 , which catalyze the oxidation-reduction reaction of Cr 3+ /Cr 2+ . In situ differential electrochemical mass spectrometry monitoring of the hydrogen evolution signal demonstrates a clear inhibition of the hydrogen evolution reaction. Notably, the addition of 40 mM Pb 2+ significantly reduces the overpotential of the reaction, allowing the battery's energy efficiency to reach 83.90% at a current density of 140 mA·cm -2 , which represents a 5.68% increase compared to the original electrolyte (78.22%). Furthermore, this configuration enables long-term stable operation over 400 cycles. This research presents an innovative approach to enhancing the performance of iron-chromium redox flow batteries, characterized by its simplicity and cost-effectiveness.
研究领域:
储能
·
电化学
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材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Kang Li,Yang Hanpei,Wang Lina,Chai Siqi,Zhang Ruichen,Wu Junming,Liu Xiaona
In this study, a novel composite composed of iron monosulfide nanoparticles (FeS NPs) and titanate nanotubes (TNTs) was hydrothermally synthesized. Characterizations revealed the encapsulation and homogenous dispersion of FeS NPs into the interlayers of TNTs. Significant performance in removal of aqueous total Cr was acquired by efficient conversion of Cr(VI) to Cr(III) on FeS and simultaneous adsorption of Cr(III) on TNTs. Moreover, the high activity of FeS-TNTs in reduction of Cr(VI) can maintain at high oxicity or alkalinity of its solution. The synergistic effect between FeS and TNTs was derived from sheltering of FeS NPs from their self-aggregation, O 2 -oxidation and the affinity of Cr(III) to TNTs. The unique properties, e.g. the solid acidity, the hollow and interlayered configuration of TNTs played important roles in high activity, good stability and reusability of FeS-TNTs.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Qiuping Li,Shaopeng Gu,Liang Yu,Jingmeng Dong,Zerong Duan
Chromium (Cr) slag, a byproduct of steelmaking, is an important recyclable secondary resource. The preparation of Na 2 CrO 4 from Cr slag has the potential to enhance the economic value of the slags and address environmental challenges linked to Cr(VI). This study investigated the heating processes of Cr slag without and with 30 wt.% Na 2 CO 3 under different atmospheres (air and argon) from 30 ℃ to 1400 ℃. The results showed that 30 wt.% Na 2 CO 3 reacted with Cr 2 O 3 and FeCrO 4 , starting to form Na 2 CrO 4 at 915 ℃ in air. When the heating temperature exceeded 1200 °C, Na 2 CrO 4 started to volatilize, which can be collected. Conversely, heating Cr slag with Na 2 CO 3 in argon generated NaCrO 2 without Cr volatilization. This research proposed a green one-step and cost-effective method for Na 2 CrO 4 preparation: Cr slag heated with 30 wt.% Na 2 CO 3 in air to 1400 ℃. It can use the residual heat from steelmaking, contributing to the recovery and utilization of secondary resources.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL GEOLOGY
·
2024
·
IF 3.6
Xinting Lü,Detao He,Yongsheng Liu,Ming Li,Jie Lin,Wei Chen,Lüyun Zhu,Ao Yang,Yantong Feng,Zhenyi Liu,Xianli Zeng,Zhaochu Hu
Iron oxide minerals, such as hematite and magnetite, are commonly found in a wide range of geological environments. Their Fe isotopic composition acts as a potent geochemical tracer, finding applications across various realms of Earth sciences. However, natural iron oxide minerals often have a high Cr content up to percentile levels, necessitating correction of isobaric interference caused by 54 Cr + on 54 Fe + to ensure accurate and precise in situ Fe isotopic compositions. In this study, a pure chromium metal with homogeneous isotopic compositions was examined within the analysis sequence to obtain the fractionation factor of Cr (β Cr ) for isobaric interference correction. A femtosecond laser ablation system combined with wet plasma conditions was used to decrease the matrix effect. We synthesized a series of magnetite and hematite samples with simple matrix as well as natural magnetite samples with complex matrix to evaluate the feasibility of Cr interference correction. By employing our proposed correction method, the deviation caused by the isobaric interference of 54 Cr + was effectively eliminated. The corrected δ 56 Fe values for hematite and magnetite samples, even with a Cr/Fe ratio of as high as 1.27, exhibited good agreement with the reference values within the long-term reproducibility uncertainty of 0.10‰. These results indicate the robustness of Cr interference correction in obtaining accurate Fe isotopic compositions of Cr-rich iron oxides.
研究领域:
地球化学
·
地质学
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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）