Environmental Science-Processes & Impacts
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2025
·Vol. 27
·期 2
·453-462
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IF 3.9
Situ Mu,Qi Yang,Chenxu Yan,Tong Xu,Jing Zhang,Junjun Ma,Chun Liu
Trivalent chromium (Cr3+) is a heavy metal widely present in tannery wastewater, and organic ligands represented by gallic acid (GA) have significant effects on the environmental behavior of Cr3+. This study explored the binding process of Cr3+ with GA through the integration of ultraviolet-visible (UV-vis), Fourier transform infrared (FTIR), and fluorescence spectroscopy coupled with two-dimensional correlation analyses (2DCOS). UV-vis results showed that the average molecular weight of the solutions gradually increased with the addition of Cr3+ ions. The vibration of FTIR characteristic peaks indicated that the hydroxyl and carboxyl functional groups of GA were complexed with Cr3+ ions. On the basis of the fluorescence quenching of GA after the addition of Cr3+ ions, the complexation coefficient was calculated as 4 × 104. 2DCOS and nuclear magnetic resonance (NMR) spectra demonstrated the binding sequence of GA with Cr3+ as meta-hydroxyl groups → carboxyl groups → para-hydroxyl groups, and heterospectral 2DCOS showed that the intensity change in UV-vis absorption bands occurred before that in IR absorption bands. Density functional theory (DFT) was used to quantify the binding energy of GA with Cr3+ at different binding sites, and it was shown that the binding energy of the meta-hydroxyl group was the lowest. Overall, this study provides a new approach to the analysis of the molecular structure of complexes and the binding process between organic ligands and metal ions in wastewater.
研究领域:
环境科学
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化学
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DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
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2025
·
IF 4.7
Yu Wang,Lkhamsuren Bayarjargal,Maxim Bykov,Elena Bykova,Dominik Spahr,Konstantin Glazyrin,Victor Milman,Bjoern Winkler
We synthesized three carbonates, Cr2[CO3]3, Cr2[C2O5][CO3]2, and Cr2[CO3][O]2, containing Cr3+ by laser heating of chromium oxides in CO2 at pressures between 45 and 55 GPa. All phases were characterized by single-crystal X-ray diffraction and Raman spectroscopy, while density functional theory calculations complemented the experimental results. The structure of Cr2[CO3]3-P63/m contains coplanar groups, and a 4f Wyckoff site is half occupied by Cr3+. Cr2[C2O5][CO3]2-C2/c is characterized by coplanar [CO3]2− and pyro-[C2O5]2− anions and is isostructural to Al2[C2O5][CO3]2. It was obtained only after prolonged laser heating. The oxycarbonate Cr2[CO3][O]2-Pbcn was synthesized at the highest pressure (55 GPa) studied here. In this structure, half of the oxygen atoms coordinate one carbon and two Cr atoms, while the other half coordinate three chromium atoms. The oxidation state of chromium in the carbonates is +3, independent of the oxidation state (+3 or +4) of chromium in the oxide starting material. We observed the transformation of Cr2O3-R3̅c to Cr2O3-Pbcn above 45(2) GPa after laser heating.
研究领域:
矿物学
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材料科学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
·
IF 12.2
Xia Liu,Ming Chen,Dengjun Wang,Feng Du,Nan Xu,Wu Sun,Zhaoxiang Han
Iron-based materials such as nanoscale zerovalent iron (nZVI) are effective candidates to in situ remediate hexachromium (Cr(VI))-contaminated groundwater . The anaerobic bacteria could influence the remediation efficiency of Cr(VI) during its cotransport with nZVI in porous media . To address this issue, the present study investigated the adsorption and reduction of Cr(VI) during its cotransport with green tea (GT) modified nZVI (nZVI@GT) and iron sulfides (FeS and FeS 2 ) in the presence of D. vulgaris or S. putrefaciens in water-saturated sand columns. Experimental results showed that the nZVI@GT preferred to heteroaggregate with FeS 2 rather than FeS, forming nZVI@GT-FeS 2 heteroaggregates. Although the presence of D. vulgaris further induced nZVI@GT-FeS 2 heteroaggregates to form larger clusters, it pronouncedly improved the dissolution of FeS and FeS 2 for more Cr(VI) reduction associated with lower Cr(VI) flux through sand. In contrast, S. putrefaciens could promote the dispersion of the heteroaggregates of nZVI@GT-FeS 2 and the homoaggregates of nZVI@GT or FeS by adsorption on the extracellular polymeric substances , leading to the improved transport of Fe-based materials for a much higher Cr(VI) immobilization in sand media. Overall, our study provides the essential perspectives into a chem-biological remediation technique through the synergistic removal of Cr(VI) by nZVI@GT and FeS in contaminated groundwater. Environmental implication The green-synthesized nano-zero-valent iron particles (nZVI@GT) using plant extracts (or iron sulfides) have been used for in situ remediation of Cr(VI) contaminated groundwater. Nevertheless, the removal of Cr(VI) (including Cr(VI) adsorption and Cr(III) generation) could be influenced by the anaerobic bacteria governing the transport of engineered nanoparticles in groundwater. This study aims to reveal the inherent mechanisms of D. vulgaris and S. putrefaciens governing the cotransport of nZVI@GT combined with FeS (or FeS 2 ) to further influence the Cr(VI) removal in simulated complex groundwater media. Our findings provides a chemical and biological synergistic remediation strategy for nZVI@GT application in Cr(VI)-contaminated groundwater.
研究领域:
环境科学
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微生物学
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DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2025
·
IF 6.7
Qian Zuo,Bing Li,Zhiyi Deng,Xiangyu Zheng,Ping Li,Jinhua Wu
Zero-valent iron (Fe 0 ) is widely packed in filters for Cr(VI) removal, but it suffers from ferrochrome precipitate passivation. In this study, a mixed Fe 0 and biochar (BC) system was established and investigated for promoted Fe 0 corrosion and enhanced Cr(VI) removal through iron‑carbon micro-electrolysis (IC-ME) by batch and column experiments with Fe 0 and BC as controls. Due to electrochemical reaction between Fe 0 and BC, there was an enhancement in iron corrosion and subsequent formation of secondary minerals on Fe 0 surface. These minerals included magnetite, lepidocrocite, and goethite, which facilitated Cr(VI) adsorption and reduction. The Fe 0 -BC system therefore obtained a higher Cr(VI) removal rate of 86.3 % within 6 h than those of the BC (7.9 %) and Fe 0 (12.5 %) systems. Chromium species distribution showed that 76.2 % of removed Cr(VI) was converted to Cr(III). The resultant Cr(III) of 68.4 % was immobilized on Fe 0 and BC surfaces due to precipitation and sequestration. The optimal Fe/BC mass ratio was 2:1 for galvanic reaction and Cr(VI) removal. The removal of Cr(VI) by Fe 0 -BC exhibited a pH-dependency, with acidic conditions favoring higher removal rates. Additionally, the column experiment result revealed that Cr(VI) removal capacity of 4.0 mg Cr(VI)/(g Fe 0 ) and operational lifespan of 1851 PV in the Fe 0 -BC column were 6.7 and 3.9-fold greater than those in the Fe 0 column, further confirming that galvanic reaction could effectively alleviate Fe 0 surface passivation. These results indicated that mixed Fe 0 and BC as an effective medium in filter tanks could form IC-ME to enhance Cr(VI) reduction and immobilization during water treatment.
研究领域:
环境科学
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水处理工程
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DOI
高影响因子
IONICS
·
2025
·
IF 2.6
Li Runze,Guo Yang,Yuan Shiling,Liu Gang,Lin Meng
Iron-chromium flow battery is considered one of the preferred technologies for large-scale energy storage facilities due to its advantages of low pollutability, less cost and high safety. However, the poor reversibility of the Cr 3+ /Cr 2+ redox reaction at the anode of iron-chromium flow batteries, the low activity and the susceptibility to hydrogen evolution reaction are the primary problems that restrict the development and application of this battery. On the basis of graphite felt electrodes, we prepared bismuth-lead oxides co-modified graphite felt electrodes via acid etching and electrodeposition method to improve the electrochemical performance in the reaction kinetics. The structural and catalytic properties of the materials were characterized and evaluated by scanning electron microscopy, X-ray photoelectron spectroscopy, X‐ray diffraction spectroscopy and electrochemical methods, respectively. The results show that with the help of the interaction between Bi and Pb elements, the successfully prepared modified electrode not only improves the reversibility and reaction rate of the electrochemical redox reaction of Cr 3+ /Cr 2+ but also effectively inhibits the occurrence of hydrogen evolution reaction.
研究领域:
材料科学
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电化学
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DOI
高影响因子
DIAMOND AND RELATED MATERIALS
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2024
·
IF 4.3
Tao Chen,Luzhao Xing,Shaojun Niu
Here, a novel magnetic nitrogen-rich biochar (MNRB), synthesized by attaching Fe 3 O 4 @SiO 2 -NH 2 particles with core-shell structure on crab shell derived/nitrogen-rich biochar (NRB), was used as absorbent and reductant to remove hexavalent chromium in aqueous systems. Characteristics of the material demonstrated that the MNRB was rich in nitrogen-containing functional groups and that the Fe 3 O 4 @SiO 2 -NH 2 magnetic particles with a diameter of approximately 150 nm were successfully added on the MNRB surface by strong ether linking (C-O-C). The maximum removal capacity of MNRB was 152.9 mg·g −1 , which was considerably higher than most reported magnetic biochar. Study of the removal mechanisms revealed that the Cr(VI) removal by MNRB involved three steps: (1) adsorption of Cr(VI) anions by protonated functional groups; (2) reduction of Cr(VI) anions to Cr(III) cations by electron-donor groups; and (3) chelation of Cr(III) cations by amine groups. The easy regeneration, satisfactory reusability, and remarkable performance in batch tests reflected the high potential of MNRB for treating Cr(VI)-contaminated water.
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 HAZARDOUS MATERIALS
·
2025
·
IF 11.3
Cuili Xing,Xinyi Yao,Kaiwei Zheng,Yang Liu,Yuankui Sun,Xiaohong Guan
Efficient removal of recalcitrant Cr(III)-organic complexes is always challenged by slow decomplexation process and the possible accumulation of highly toxic Cr(VI). Herein, a sulfidated zero-valent iron coupled ozonation strategy (S-ZVI/O 3 ) was proposed to achieve efficient decomplexation and simultaneous abatement of Cr(III)-EDTA without Cr(VI) accumulation. Results revealed that S-ZVI could catalyze O 3 to enhance removal of Cr(III)-EDTA and total organic carbon. Moreover, 88.3 % of total Cr was sequestrated by S-ZVI/O 3 and the corresponding kinetic constant was 3.1 times higher than that of ZVI/O 3 . Mechanistically, electron paramagnetic resonance and probing tests verified HO • was the dominant reactive oxidation species for decomplexation of Cr(III)-EDTA in both S-ZVI/O 3 and ZVI/O 3 . More attractively, it was found that structural Fe(II) was the major O 3 activator in S-ZVI/O 3 , whereas dissolved Fe 2+ accounted for O 3 catalyzation in ZVI/O 3 . The X-ray absorption spectroscopy analysis revealed that sulfidation treatment could enhance corrosion of ZVI with the formation of sufficient Fe(II) species. The in-situ formed Fe(II) could not only transform undesired Cr(VI) back to Cr(III) but also co-precipitate with Cr(III) to form solid Fe-Cr hydroxides. Besides Cr(III)-EDTA, S-ZVI/O 3 is also applicable to other EDTA complexed heavy metals. This work would provide a new method for the heavy metal complexes removal from water.
研究领域:
环境科学
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化学工程
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DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
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IF 8.1
Biao Yuan,Pan Wu,Changjun Liu,Jian He,Wei Jiang
The challenge of separating and recovering V(V) and Cr(VI) from wastewater is critical for environmental protection and industrial productivity due to the chemical similarities. In this study, a novel zirconium-based adsorbent with superior adsorption performance and selectivity was synthesized using the Sol-Gel method, with a specific surface area of up to 265.3 m 2 /g. The maximum adsorption capacities of V(V) and Cr(VI) were 222 and 123 mg/g, respectively. The adsorption process followed the Langmuir isothermal adsorption and the pseudo-second-order kinetic model. The adsorption mechanism was thoroughly investigated confirming that the adsorption of V(V) and Cr(VI) on amorphous hydrous ZrO 2 (AHZOs) is chemisorption. At a pH of 3, the values of ΔG 0 (−46.8 kJ/mol) and E ads (−5.67 eV) for the main existing form H 3 V 10 O 28 3- on AHZOs are lower than those for the main existing form HCrO 4 - . V(V) replaced the adsorbed Cr(VI) during competitive adsorption to achieve selective adsorption of V(V) with a separation coefficient as high as 3142. The adsorption capacity of V(V) remains above 105 mg/g after five cycles. After adsorption, the purity of Cr(VI) can be increased to above 99.5 %, and a solution of V(V) with a purity higher than 99.25 % can be obtained after desorption. The use of 3 g/L and 100 g/L adsorbent can decrease the single V(V) and Cr(VI) to 1.618 mg/L and 0.36 mg/L, respectively, and meet the emission standards.
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
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Wenqiang Wang,Guanghui Zhang,Lihua Dong,Ping Gu,Shiyuan Ding,Lian Hou
Persistent toxic heavy metal Cr(Ⅵ) oxyanions is increasingly damaging to the environment and human life safety. In this study, a novel tertiary amine chloride type cationic covalent organic framework with high yield (>95%) was synthesized using a one-step Schiff base reaction by room temperature standing two functional monomers . The adsorbent was characterized by SEM, EDS , FTIR , NMR , PXRD , BET, TGA and pH PZC . And a series of adsorption experiments were conducted to verify the removal effect for Cr(Ⅵ). It exhibited excellent adsorption performance and the adsorption equilibrium time was within 10 min, superior to most adsorbents. The adsorption conformed to the pseudo-second-order kinetics and the Langmuir adsorption isothermal models based on the values of R 2 and RMSE in the corresponding four models. The impact of pH was significant, and the maximum adsorption capacity was 161.4 mg/g at a pH of 2. The adsorbent had good adsorption selectivity for Cr(Ⅵ) oxyanions in the presence of coexisting ions (Cl − , SO 4 2− , NO 3 − , and PO 43 − ), and good recyclability with only decrease of removal rate from 98.3% to 91.5% after five cycles. The mechanism for Cr(Ⅵ) adsorption was mainly attributed to ion exchange, and hydrogen bonding also played a subordinate role. In the Cr(Ⅵ)-MO binary system, the increase for Cr(VI) adsorption results from the new active sites in methyl orange. This work highlights the mild synthetic conditions, fast adsorption rate, and good adsorption of Cr(Ⅵ), which make it a promising prospect.
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
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Chao Duan,Shasha Che,Guodong Tian,Yiyang Che,Xiaoran Nie,Lei Dai
Abundant hazardous pollutants, in particular heavy metal ions and microbes, in aqueous systems seriously threaten ecological safety and human health. Photocatalysis is deemed an appealing solution yet remains challenging to exploit more efficient, economical, and sustainable photocatalytic materials. In this study, we successfully fabricated a cellulose paper-based composite membrane, namely Zr-TCPP@PDA@FP, for photoreduction of Cr(VI) and photothermal antimicrobial. For the resultant composite membrane, the self-polymerization polydopamine (PDA)-coated cellulose fibers act as sustainable scaffolds to anchor the in-situ synthesized porphyrin-doped UiO-66-NH 2 (Zr-TCPP) nano-photocatalysts. The hypotheses are that: 1) porphyrin doping in Zr-TCPP can both reinforce the visible-light absorption and the transport of photogenerated electrons; 2) mussel-inspired PDA coating on fiber surface not only services as binder to promote the Zr-TCPP loading and dispersion, but also functions as heterojunction interface to accelerate photogenerated electron separation and transfer from Zr-TCPP; As a result, Zr-TCPP@PDA@FP exhibited significant photocatalytic reduction towards Cr(VI), achieving a removal efficiency of 93.9 % within 20 mins and cycling stability. Besides, the hybrid membrane also featured excellent photothermal antibacterial performance (over 99 % for both E. coli and S. aureus ). This work will inspire the development of economic and sustainable cellulose-based functional materials for efficient wastewater remediation.
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
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Tong Hu,Wenjun Zhou,Haijiao Xie
Lattice engineering of Fe 0 based on heteroatom doping holds great promise in water purification owing to their tunable geometric and electronic structure. However, there is limited understanding of how nitrogen atom in Fe 0 lattice structure affects its local microenvironment and corresponding reactivity toward target contaminants. Herein, microscale zero-valent iron with interstitial N doping (N-mZVI) was successfully prepared by a facile mechanochemical method for heavy metal pollution control. N-mZVI exhibited excellent reactivity for Cr(VI) elimination, and both removal efficiency and conversion rate could reach 100 %, which was 8.06 and 2.73 times higher than that of pristine ball milled mZVI, respectively. Besides, the rate constant of various heavy metals sequestration (Cr(VI), Ni(II), Pb(II), Cu(II), and Cd(II)) over N-mZVI was 61.3 ∼ 115.6-fold faster than that of pristine ball milled mZVI. N-mZVI was also demonstrated to be pH-universal, long-term stability, and environmental applicability. Experimental results and theoretical calculations indicated that tensile strain induced by interstitial N doping expanded Fe 0 lattice and weakened the lattice Fe-Fe interaction, thus significantly accelerating electron transport dynamics in Fe 0 core. Meanwhile, iron nitride species on the surface of N-mZVI promoted electron transfer from iron shell layer to heavy metals. This work comprehensively investigates the structure–property relationships of lattice engineering-based N-mZVI, and provides a new insight into rational design of modified mZVI with high reactivity.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Yixuan Wang,Yuanhang Xiao,Keshuai Ren,Chunhua Wang,Huiyong Sun,Wei Lin
Chrome-free tanning is an emerging trend for the green sustainable development of the leather manufacturing industry. However, conventional anionic wet finishing materials for chrome-tanned leather are not suitable for chrome-free tanning systems due to the imbalance of surface charge between the wet finishing materials and chrome-free tanned leather. In this paper, we have developed a novel and facile approach to synthesizing an amphoteric polymer named PAMLD as a retanning/fatliquoring agent for chrome-free tanned leather. The PAMLD polymer with a suitable particle size (d = 325 nm) and appropriate isoelectric point (pI = 4.6) was prepared by one-step copolymerization in an aqueous solution using acrylic acid (AA), methacrylic acid (MAA), ethyl methacrylate trimethylammonium chloride (DMC), and dodecyl 2-methyl acrylate (LMA) as monomers. The obtained amphoteric polymer was further applied in the wet finishing processing of three types of chrome-free tanned leather. Comprehensive characterizations of leathers treated with PAMLD indicated the retanning and fatliquoring effect of PAMLD on collagen fibers. Moreover, leathers treated with PAMLD exhibited better dyeing properties compared with those treated with the commercial amphoteric wet finishing material (FRA), as evidenced by their superior K/S values and color fastness to rubbing and washing. This research not only provides a feasible approach for preparing multifunctional amphoteric polymers but also offers novel matching wet finishing materials and strategies for variable chrome-free tanned leather production.
研究领域:
制革化学
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环境科学
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高分子化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）