Journal of Environmental Sciences
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2025
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IF 6.3
Yuanyuan Wang,Shijun Jia,Shiqiang Ding,Wenyan Zhang,Rui Shu,Yingfei Hu
Using natural minerals to eliminate harmful Cr(VI) under sustainable sunshine has significant potential. Herein, Palygorskite nanorods were utilized as carriers for the in-situ synthesis of CaIn 2 S 4 photocatalysts through a simple one-pot thermal process, enabling the efficient reduction of Cr(VI). With a Palygorskite to CaIn 2 S 4 mass ratio of 5 %, the conversion rate of Cr(VI) reached 98 % after 60 minutes of visible-light exposure, with a remarkable reaction rate of 0.0633 min −1 . The effective integration of CaIn 2 S 4 with Palygorskite led to a more uniform dispersion of CaIn 2 S 4 , exposing more reactive sites. Moreover, the establishment of a heterojunction between CaIn 2 S 4 and Palygorskite facilitated the transport of photogenerated electrons from CaIn 2 S 4 , enhancing the efficiency of charge separation. These factors contribute to the improved photocatalytic performance. Additionally, the developed composite photocatalysts demonstrated excellent stability under light exposure and could be reused efficiently. Trapping tests on active substances revealed that e − played key roles in the Cr(VI) reduction. This research suggests the potential of using natural minerals to fabricate composite photocatalysts capable of effectively removing pollutants from the environment using solar energy.
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
GEOMICROBIOLOGY JOURNAL
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2015
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IF 1.44
Hongliang Liu,Jun Huang,Shengzhe Zhang,Biao Xu,Gejiao Wang
This study was conducted to determine the microbe-chromate [Cr(VI)] interaction and the effect of quinoid analogue anthraquinone-2-sulfonate (AQS) on aerobic Cr(VI) reduction by Intrasporangium chromatireducens Q5-1. The addition of redox mediator AQS, which might expedite the electron transfer, promoted Cr(VI) bioreduction. Addition of carbon sources, such as maltose, acetate, sucrose and lactose stimulated the AQS-promoted Cr(VI) reduction of strain Q5-1. Induction experiment clarified that the enzyme involves in the Cr(VI) reduction is constitutive. Energy-dispersive spectroscopy (EDS) spectra showed the existence of trace Cr distributed on the cell surface. X-ray photoelectron spectroscopy (XPS) analysis revealed that the Cr(III) complex was bound to the cell surface (0.87%, atomic percent). The spectra shifts detected by Fourier transform infrared (FTIR) spectroscopy indicated that Cr(III) was bound to the carbonyl and amide groups. In addition, Cr(VI) reduction by different cell fractions showed that Cr(VI) reduction was occurred extracellularly rather than intracellularly. The results disclosed that Cr(VI) detoxification of strain Q5-1 was mainly associated with extracellular Cr(VI) reduction process in combination with trace Cr(III) adsorption on the cell surface. A schematic figure depicting the interactions between strain Q5-1 and Cr(VI) was presented. This study enhanced the understanding of the microbe-Cr(VI) interaction mechanism and revealed the AQS-promoted aerobic Cr(VI) reduction of strain Q5-1. Such strain and quinoid analogue-mediated bacterial Cr(VI) reduction may facilitate the bioremediation for Cr(VI)-polluted environment.
研究领域:
微生物学
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环境科学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Jingjing Wang,Zhiwei Liu,Liying Wang,Lu Li,Qian Liu,Zhiwei Liu,Zhenzhu Cao,Yongfeng Zhang,Lin Cheng,Jucai Yang
Type II heterojunction photocatalysts possessed excellent redox properties and had great potential for environmental remediation applications. In this paper, a novel Bi source of Bi-MOF was created by using NaBiO 3 . Additionally, KCl was incorporated to contest Bi-MOF for the Bi source, with the objective of generating floral BiOCl. Subsequently, heterostructures based on metal-organic skeletons (MOFs) were constructed with Bi-MOF and BiOCl, with the aim of exposing the (002) crystal faces of BiBDC. The modification of the (002) crystal surface was employed to create holes or generate more photogenerated electrons, resulting in efficient degradation of rhodamine B (RhB) and simultaneous reduction of hexavalent chromium. The heterogeneous structure demonstrated a degradation rate of 97 % for rhodamine B (RhB) after reaching adsorption equilibrium in 30 min of dark reaction and 10 min of visible light irradiation. Furthermore, the reduction rate of hexavalent chromium (Cr (VI)) was 95.5 % after reaching adsorption equilibrium in 30 min of dark reaction and 70 min of visible light irradiation . The results of the cycling experiments demonstrated that both 1:1 BBOC and 1:3 BBOC retained their structural integrity following four cycles. The active species trapping results indicated that the hole radicals (h + ) and electrons were responsible for the degradation of RhB and the reduction of hexavalent chromium, respectively. This study also revealed the degradation pathways and mechanisms of heterojunctions, providing new ideas for the preparation of photocatalysts for environmental 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
ACS ES&T Engineering
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2022
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IF 0
Ting Zhang,Zhelun Pan,Dinggui Song,Hong Huang,Jiang Yu,Yichan Wen,Junlin Lu,Zhenfeng Bian,Xufang Qian
The high reactivity of Fe(0) with Cr(VI) makes it the best choice for Cr(VI) removal. Interstitial compound Fe3C was produced during the carbothermic reduction of mesoporous phenolic resin/ferric ions to form Fe(0)/Fe3C nanoparticles embedded in mesoporous carbon (Fe(0)/Fe3C@MesoC). Fe3C accelerates the electrochemical corrosion process of α-Fe(0) in solution, and the positive/negative equipotential interface that is formed by iron–carbon (Fe–C) microelectrolysis of Fe(0)/Fe3C@MesoC induces the capture of Cr(VI) anions and Cr(III) cations as a result of this process. Cr(VI) was completely reduced to Cr(III) by the Fe(0)/Fe3C@MesoC catalyst with a high electron efficiency (40.5%) relative to nanosized zero-valent iron (1.9%) and Fe@MesoC (32.7%). Surface ferrous ions are the principal reactive species responsible for Cr(VI) reduction (at least 64%); Fe(0)/Fe3C and undetectable surface ferrous ions account for a small part of Cr(VI) reduction (around 28%), and only 8% of Cr(VI) ions are reduced by active hydrogen (H*). The proposed structure of Fe(0)/Fe3C@MesoC provides new insight into iron–carbon material preparation and application in in situ chemical reduction.
研究领域:
环境科学
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材料科学
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DOI
CHEMISTRY-A EUROPEAN JOURNAL
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2019
·Vol. 25
·期 41
·9710-9720
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IF 5.16
Dawei Zhao,Tengteng Wu,Yi Zhou
Graphical Photofit : Fabricating a high-performance photocatalyst to efficiently solve serious environmental problems is an urgent affair. A series of MoS 2 /ZnO composites were successfully fabricated through a facile hydrothermal route, leading to a highly efficient MoS 2 /ZnS/ZnO ternary photocatalyst for environmental treatment. Fabricating a high-performance photocatalyst to efficiently solve serious environmental problems is an urgent affair. Herein, a series of MoS 2 /ZnO composites were successfully fabricated through a facile hydrothermal route using Na 2 MoO 4 , (NH 2 ) 2 CS and urchin-like ZnO as precursors. According to the results of XRD and XPS, it was found that ZnS appeared in MoS 2 /ZnO composite; meanwhile, the content was positively correlated with the weight of the precursor (NH 2 ) 2 CS. It should be noted that the morphology and the metallic phase content of MoS 2 grown in situ on the surface of ZnO were affected by the molar ratio of Na 2 MoO 4 and ZnO. Benefiting from the special dual II heterojunctions of MoS 2 /ZnS/ZnO ternary composite, the material exhibited excellent charge separation and transfer performances. In the photocatalytic measurements, the MoS 2 /ZnS/ZnO (Na 2 MoO 4 :ZnO 1:2 MZ2) composite not only exhibits excellent photocatalytic Cr VI reduction activity of 42.3×10 −3 min −1 , but also displays remarkable adsorption performance (nearly 32.1 %) for Cr 2 . In addition, the ternary composite shows dominant photocatalytic Cr VI reduction activities compared to other photocatalysts. This work provides a high-efficient MoS 2 /ZnS/ZnO ternary photocatalyst for environmental 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
CHEMICAL ENGINEERING JOURNAL
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2021
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IF 13.273
Minzhang Li,Rajendran Ramachandran,Thangavel Sakthivel,Fei Wang,Zong-Xiang Xu
In this work, we reported the synthesis of siloxene catalysts from calcium silicide at various topotactic reaction conditions and demonstrated their photocatalytic activity for Cr(VI) reduction under visible light irradiations. The topotactic reaction time influenced the surface area, structure, and optical characteristics of the siloxene, which altered the Cr(VI) photocatalytic elimination efficiency. A large specific surface area (47.04 m 2 g −1 ) and a narrow bandgap (2.45 eV) with hydroxyl-terminated layered silicon of the S-12 h catalyst could enable more active sites for photocatalytic reaction, which results in the improved catalytic performance for Cr(VI) removal. The Density Functional Theory calculations proved the siloxene’s direct bandgap feature and narrow bandgap. The initial Cr(VI) concentration, solution pH, temperature, inert gas, and different scavenger's effects on the photocatalytic performance of the S-12 h catalyst were also investigated. The S-12 h photocatalyst exhibited the Cr(VI) reduction efficiency of 98.6% for the electroplating wastewater that demonstrates the potential application in industrial for treatment of heavy metal ions removal.
研究领域:
环境科学
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材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2018
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IF 6.434
Xuesong Zhao,Shaobin Huang,Ying Liu,Qianyu Liu,Yongqing Zhang
In the present study, we prepared novel polyaniline supported W 18 O 49 (PANI/W 18 O 49 ) nanocomposite by in situ oxidative polymerisation method. We herein focused on enhancing the stability and the photocatalytic performance of W 18 O 49 . The prepared PANI/W 18 O 49 was thoroughly characterized by FTIR, TEM, XRD, BET, UV–vis DRS and PL. The PANI support presented a great effect on the light harvesting and photo-charge transfer of the W 18 O 49 , and the optimum percentage of was found to be 10 wt%. As for treating Cr(VI), the effect of important water quality parameters (such as pH, ions, NOM, DO, temperature and SOAs) on photocatalytic performance was investigated under the visible light irradiation (λ > 420 nm). SOAs were shown to exert a dramatic accelerating influence on Cr(VI) reduction in the system. The obtained 10%-PANI/W 18 O 49 can completely catalytically reduce 1 mM Cr(VI) in the presence of tartaric acid (1:3) within 50 min. Meanwhile, it can be recycled at ten times without any loss of photocatalytic efficiency, indicating the high stability of the as-prepared photocatalyst. The results of the study demonstrate the potential of the new obtained photocatalyst in efficient utilization of solar energy for treating aqueous Cr(VI).
研究领域:
材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
Catalysis Science & Technology
·
2018
·Vol. 8
·期 13
·3238-3245
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IF 5.365
Hongxu Yan,Yunyi Liu,Tao Zhang,Ze Jin,Ming Wang,Ying Peng Xie,Hongfan Guo
Pd catalysts, which are often prepared by reducing Pd salts with NaBH4, have been intensely studied in HCOOH dehydrogenation (FAD) for H2 production. FAD can also be used to hydrogenate or reduce various chemicals by using its in situ generated hydrogen, which exhibits superiority over the direct use of H2 gas. Herein, by using FAD to reduce Cr(VI) as a room-temperature probe reaction, we show that some Pd atoms in the catalyst form PdHx under normal conditions during both catalyst preparation and catalytic reaction (NaBH4 or HCOOH as a hydrogen donor). PdHx greatly hinders Cr(VI) reduction and, interestingly, boosts H2 generation. That is to say, PdHx can be negative or positive species, depending on the focused product. The reason for this phenomenon was also analyzed. Heat treatment for only 10 min can destroy PdHx species and thus, improve the activity for Cr(VI) reduction by up to ∼3 times, which is effective in each catalyst reuse. These findings are critical for controlling the design and functioning of Pd catalyst.
研究领域:
催化化学
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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
·
IF 13.3
Zijun Xu,Ruoxin Ma,Chun Zhang,Jiao Chen,Jingbiao Fan,Qingdong Shi
Cr(VI) pollution in water caused by industrialization poses a serious threat to human health and ecosystems, necessitating a rapid reduction of Cr(VI) treatment method. Therefore, We have established a photocatalytic method for the rapid reduction of Cr(VI) by modifying TiO 2 with carbon dots (CPC-CDs) that possess a quaternary ammonium structure in the first time. The CPC-CDs widens the band gap of TiO 2 and increases the electrostatic interactions between CPC-CDs/TiO 2 and Cr(VI), thus improving the reduction efficiency. CPC-CDs/TiO 2 (0.1 g, 2 % CPC-CDs) exhibited excellent reduction performance and fully reduced Cr(VI) (50 mg/L) under neutral conditions within 150 min using a xenon lamp to simulate sunlight. Moreover, CPC-CDs/TiO 2 achieved more than 95 % reduction efficiency over a wide pH range (pH = 3, 5, 7, and 9) and showed excellent reduction of Cr(VI) at various concentrations (10, 20, 30, 40 and 50 mg/L). CPC-CDs/TiO 2 maintained high Cr(VI) reduction efficiency (93.57 %) after five cycles. Tests under real sunlight revealed that CPC-CDs/TiO 2 thoroughly reduced Cr(VI) (10 mg/L) within 30 min, and exhibited excellent structural stability under conditions with interfering ions. Furthermore, CPC-CDs/TiO 2 exhibited prominent antibacterial activity against Escherichia coli . In addition, free-radical trapping experiments verified that the superoxide radicals (• O 2 - ) was the main active species. This study aims to overcome the limitations of photocatalytic reduction under conditions of high concentration Cr(VI), neutral and alkaline environments, and natural sunlight, thereby providing technical support for the rapid reduction of Cr(VI).
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
CHEMICAL GEOLOGY
·
2022
·
IF 4.685
Liyan Deng,Fu Liu,Zecong Ding,Yuzhen Liang,Zhenqing Shi
Fe(II)-bearing clay minerals are abundant in soils and are critical to control the fate of the highly toxic hexavalent chromium (Cr(VI)). Even though the reduction of Cr(VI) by Fe(II)-bearing clay minerals has been extensively studied, the effect of the commonly co-existing natural organic matter (NOM) on this process is poorly understood. This study aimed to understand the kinetics of Cr(VI) reduction by a typical Fe(II)-bearing clay mineral (i.e., reduced nontronite (rNAu-2)) in the presence of Suwannee River NOM and to unveil the possible mechanisms. Cr(VI) reduction experiments were conducted with different NOM concentrations in a range of 0 to 100 mg C L −1 under circumneutral pH. The time-course aqueous-phase measurements and solid-phase characterizations were performed with a combination of wet chemical methods, transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses. The results demonstrated that NOM inhibited Cr(VI) reduction overall, mainly due to the decrease of Cr(VI) sorption on rNAu-2 by mineral-bound NOM. Besides the predominant solid Cr(III) species, soluble and mobile Cr(III) complexes were formed during reduction. Interestingly, the reduction rate ( k ) decreased with the increase of NOM concentration from 0 to 20 mg C L −1 , but kept increasing when the concentration of NOM increased from 30 to 100 mg C L −1 . The contrary pattern is due to the increasing promotion effects that offset the inhibitory effect caused by competitive sorption between Cr(VI) and NOM. The promotion effects may include weakening the mineral passivation by forming stable aqueous NOM-Cr(III) complexes, accelerating the electron transfer rate by dissolving rNAu-2, and donating electrons through NOM-Fe(II/III) complexes and/or NOM-Cr(V) complexes. This study extends our knowledge of Cr(VI) reduction by clay minerals in organic matter-rich soils and sediments and has important implication for understanding the transport and long-term behavior of Cr in the environment.
研究领域:
环境科学
·
土壤学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2021
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IF 7.086
Weichun Yang,Xiaomin Li,Dongdong Xi,Qi Li,Zhihui Yang,Xiaobo Min,Zhang Lin,Qi Liao
It is a challenge to simultaneously treat the combined pollutants of chromium(VI) (Cr(VI)) and organics (such as phenol) in wastewater. Here, a stable and efficient redox system based on FeS 2 sulfidated zero valent iron (FeS 2 /Fe 0 ) and persulfate (PS) was developed to synchronously remove Cr(VI) and phenol. 100% of phenol (10 mg/L) was oxidized in 10 min and Cr(VI) (20 mg/L) was completely reduced to Cr(III) in 90 min in the FeS 2 /Fe 0 +PS system with a pH range of 3.0–9.0, respectively. phenol was selectively oxidized without re-oxidizing Cr(III) in such system. The surface-bound Fe 2+ was the major reactive species to synchronously reduce Cr(VI) and oxidize phenol. The mechanisms were elucidated that the phenol degradation was accelerated by the generated Cr(III) complexing with its products, and that SO 4 2− , whose production speed was accelerated by the PS activation to oxidize phenol and FeS 2 , was conductive to corrode Fe 0 to regenerate the surface-bound Fe 2+ for reducing Cr(VI) and oxidizing phenol. It is potential to develop a high-performance and large-scaled FeS 2 /Fe 0 -based redox platform to remediate the complex pollution of Cr(VI) and organics.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Science & Technology Letters
·
2017
·
IF 5.308
Jun-Cheng Han,Guo-Jun Chen,Li-Ping Qin,Yang Mu
Cr isotope fractionation during microbial reduction processes is commonly recognized as a promising tool in biogeochemistry and bioremediation. However, the mechanism of Cr isotope fractionation during microbial reduction is poorly understood. In this work, the relationship between the bacterial respiratory pathway and Cr isotope fractionation was investigated in Shewanella oneidensis MR-1. For comparison with the wild type, a mutant strain (ΔomcA/ΔmtrC) with a deficiency in extracellular Cr(VI) reduction was constructed by deleting the omcA and mtrC genes, which encode the terminal reductase during extracellular reduction. The magnitudes of Cr isotope fractionation (ε) for Cr(VI) reduction by the wild type and ΔomcA/ΔmtrC were −2.42 ± 0.68‰ and −2.70 ± 0.22‰, respectively. Surprisingly, the ε values were not significantly different between the two strains. This suggests that isotope fractionation is independent of the metal respiratory pathway during Cr(VI) reduction by S. oneidensis MR-1. Moreover, a three-step Cr isotope fractionation model that includes uptake, reduction, and efflux was proposed to exist during intracellular Cr(VI) reduction by S. oneidensis MR-1. The developed model provides a better understanding of Cr isotope fractionation during microbial reduction.
研究领域:
生物地球化学
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环境微生物学
✓ 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）