Journal of Cleaner Production
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2023
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IF 11.1
Di Zhang,Hao Tang,Bing Zhao,Lijie Liu,Hongwei Pang,Xiangxue Wang,Shujun Yu
Radioactive uranium removal plays a key role in energy development and environmental security. Sulfide nanoscale zero-valent iron (S-NZVI) has good antioxidant capacity, dispersibility and activity to eliminate U(VI) from wastewater, but the removal efficiency is limited. To improve the reduction and adsorption capacity of S-NZVI, through treating Fe 3+ solution by nitro-functionalized UiO-66 (UiO-66-NO 2 ) with high porosity, UiO-66-NO 2 enhanced S-NZVI adsorbent (S-NZVI/UiO-66) was prepared by liquid phase reduction method. The smaller size and larger specific surface area of S-NZVI/UiO-66 were confirmed by a variety of characterization techniques. Based on the excellent surface structure and reactivity, the U(VI) removal capacity of S-NZVI/UiO-66 (895 mg g −1 ) was much better than S-NZVI (434 mg g −1 ) and UiO-66-NO 2 (267 mg g −1 ). The impacts of pH, background ion strength, coexisting ions and different water environments on adsorption were studied via macroscopic batch experiments. The results showed that S-NZVI/UiO-66 could remove U(VI) adequately in a wide pH range. The removal rate was basically not affected by the concentration of NaNO 3 , demonstrating that the adsorption process of U(VI) on S-NZVI/UiO-66 tended to inner surface complexation. From XPS technique combined with the results of batch adsorption experiments, it was clear that the elimination mechanisms of U(VI) by S-NZVI/UiO-66 were mainly the physical adsorption, electrostatic attraction and complexation of UiO-66-NO 2 , and the reduction and complexation of S-NZVI. Therefore, it is believed that S-NZVI/UiO-66 has a great potential to be an excellent adsorbent in the field of the environment remediation. Moreover, S-NZVI/UiO-66 promises to be a novel nanomaterial for solving the problem of radionuclide contamination in practical environments.
研究领域:
环境科学
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材料科学
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高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
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2024
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IF 1.5
Lei Miao,Zhang Jun,Liu Chang,Guo Junpeng,Li Ye
Herein, S-nZVI was synthesized to remove U(VI) from seawater. At a S/Fe ratio of 0.18 and pH of 5, adsorption of U(VI) reached equilibrium after 20 min with the removal rate of 97.93%. And the maximum adsorption capacity obtained by Langmuir isothermal model was 1177.09 mg/g. Moreover, S-nZVI exhibited selectivity in the presence of interfering ions, regeneration performance in 5 reuse cycles, and high removal efficiency in actual seawater. Mechanism investigations showed that UO 2 2+ uniformly adsorbed on S-nZVI surface was irreversibly reduced and generated UO 2 precipitates due to the electrons provided by S 2− , S 2 2− and Fe(II).
研究领域:
环境科学
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材料科学
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高影响因子
International Journal of Environmental Research and Public Health
·
2022
·Vol. 19
·期 10
·6299
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IF 4.614
Yue Lang,Yanan Yu,Hongtao Zou,Jiexu Ye,Shihan Zhang
Trichloroethylene (TCE) is one of the most widely distributed pollutants in groundwater and poses serious risks to the environment and human health. In this study, sulfidated nanoscale zero-valent iron (S-nZVI) materials with different Fe/S molar ratios were synthesized by one-step methods. These materials degraded TCE in groundwater and followed a pathway that did not involve the production of toxic byproducts such as dichloroethenes (DCEs) and vinyl chloride (VC). The effects of sulfur content on TCE dechlorination by S-nZVI were thoroughly investigated in terms of TCE-removal efficiency, H2evolution, and reaction rate. X-ray diffraction (XRD) and X-ray Photoelectron Spectroscopy (XPS) characterizations confirmed Fe(0) levels in S-nZVI were larger than for zero-valent iron (nZVI). An Fe/S molar ratio of 10 provided the highest TCE-removal efficiencies. Compared with nZVI, the 24-h TCE removal efficiencies of S-nZVI (Fe/S = 10) increased from 30.2% to 92.6%, and the Fe(0) consumed during a side-reaction of H2evolution dropped from 77.0% to 12.8%. This indicated the incorporation of sulfur effectively inhibited H2evolution and allowed more Fe(0) to react with TCE. Moreover, the pseudo-first-order kinetic rate constants of S-nZVI materials increased by up to 485% compared to nZVI. In addition, a TCE degradation was proposed based on the variation of detected degradation products. Noting that acetylene, ethylene, and ethane were detected rather than DCEs and VC confirmed that TCE degradation followed β-elimination with acetylene as the intermediate. These results demonstrated that sulfide modification significantly enhanced nZVI performance for TCE degradation, minimized toxic-byproduct formation, and mitigated health risks. This work provides some insight into the remediation of chlorinated-organic-compound-contaminated groundwater and protection from secondary pollution during remediation by adjusting the degradation pathway.Keywords:S-nZVI;sulfidation;trichloroethylene;pathway;groundwater safety
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环境科学
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化学
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PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2025
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IF 5.4
Liping Liang,Yishun Wu,Weishou Tan,Fenfen Xi,Yun Zhang,Jinhui Zhao,Xu Meng,Jianfeng Ma
This study successfully synthesized g-C 3 N 4 -S-nZVI and rGO-S-nZVI composites for U(VI) sequestration and for the assessment of microbial toxicity to bacteria and fungi. The maximum U(VI) adsorption capacities of g-C 3 N 4 -S-nZVI and rGO-S-nZVI were 662.3 mg/g and 578.0 mg/g at pH = 6.0, respectively. The adsorption kinetics followed the pseudo-second-order model, and the isotherm data were well-described by the Langmuir model. The composites had a good application prospect due to their excellent resistance to ionic interference and favorable recyclability. Analysis via X-ray absorption near-edge structure (XANES), X-ray photoelectron spectroscopy (XPS), and extended X-ray absorption fine structure (EXAFS) confirmed that U(VI) removal occurred primarily through chemisorption, with uranyl ions forming a bidentate mononuclear edge-sharing coordination complex on the iron oxide surface. The presence of reactive oxygen species inhibited the reduction of U(VI) to U(IV). Fungal toxicity assays indicated good biocompatibility of g-C 3 N 4 and rGO, while S-nZVI and its composites exhibited significant inactivation of Arthrographis arxii . The inactivation mechanism involves the synergistic effects of physical contact, dissolved Fe 2+ , and ROS generation. Sediment microbial community analysis revealed that S-nZVI caused the greatest disturbance to bacterial communities, while the composites formation mitigated their influence. It is worth noting that g-C 3 N 4 -S-nZVI exhibited the most significant anti-fungal efficacy, whereas rGO-S-nZVI had a relatively small impact on bacterial and fungal communities. This research not only provides an effective method for removing U(VI), but also clarifies the impact of material use on environmental microorganisms.
研究领域:
环境科学
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材料科学
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微生物学
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纳米技术
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放射化学
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高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
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IF 14.224
Ying Liu,Jingfeng Gao,Yuwei Wang,Wanjun Duan,Yi Zhang,Haoran Zhang,Mingyan Zhao
Antibiotic resistance genes (ARGs) and antibiotic resistant bacteria (ARB) are widespread in urban wastewater treatment plants (UWTPs). In this research, a horizontal transfer model of recipient ( Pseudomonas . HLS-6) and donor ( Escherichia coli DH5α carries RP4 plasmid) was constructed to explore the effect of sulfidated nanoscale zerovalent iron (S-nZVI) on the efficiency of plasmid-mediated horizontal transfer. When the S/Fe was 0.1, the inactivation efficiency of 1120 mg/L S-nZVI on the donor and recipient bacteria were 2.36 ± 0.03 log and 3.50 ± 0.17 log after 30 min, respectively (initial ARB concentration ≈ 5 ×10 7 CFU/mL). Effects of treatment time, S/Fe molar ratio, S-nZVI dosage and initial bacterial concentration were systemically studied. S-nZVI treatment could increase the extracellular alkaline phosphatase and malondialdehyde content of the ARB, cause oxidative stress in the bacteria, destroy the cell structure and damage the intracellular DNA. This study provided evidence and insights into possible underlying mechanisms for reducing conjugative transfer, such as hindering cell membrane repair, inducing the overproduction of reactive oxygen species , inhibiting the SOS response, reducing the expression of ARGs and related transfer genes. S-nZVI could inhibit the gene conjugative transfer while inactivating the ARB. The findings provided an alternative method for controlling antibiotic resistance.
研究领域:
环境科学
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微生物学
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水处理
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PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2025
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IF 11.3
Xin Liu,Qing Wang,Zhuanxia Zhang,Liangchun Jia,Zhenxing Shen,Tengwen Long,George Zheng Chen,Jun He,Xin Song
The co-mingled plumes of chloroethenes and per- and polyfluoroalkyl substances (PFASs) raise a major challenge for groundwater remediation. This study is the first try to apply sulfidated nano zero-valent iron supported on calcined layered double oxides (S-nZVI@LDO) for simultaneous removal of trichloroethylene (TCE) and perfluorooctanoic acid (PFOA). Our findings revealed that 2 g/L S-nZVI@LDO simultaneously removed 73.3 % TCE and 37.8 % PFOA in pure water, with 49.5 % TCE degraded to less chlorinated products and 23.8 % adsorbed or unquantified transformation of C 3 –C 6 hydrocarbons. Comparative experiments using individual and co-occurring TCE and PFOA revealed that co-existing PFOA and TCE minimally affected their respective removal efficiencies, highlighting S-nZVI@LDO’s suitability for co-contaminant remediation. Furthermore, S-nZVI@LDO achieved optimal TCE and PFOA removal under acidic conditions, surpassing non-composite S-nZVI and LDO. Based on the characterization of S-nZVI@LDO, TCE removal involved reductive dechlorination and sorption via hydrophobic interactions, while PFOA removal was primarily driven by electrostatic interactions and hydrogen bonding. In real groundwater, S-nZVI@LDO achieved 58.2 % TCE and 33.7 % PFOA removal. Additionally, S-nZVI@LDO simultaneously removed nine different PFASs from a 12-PFASs mixture and demonstrated greater effectiveness for long-chain PFASs and their alternatives (e.g., GenX) owing to their hydrophobic nature. These findings highlight the potential of S-nZVI@LDO as an effective material for TCE-PFOA co-contaminated groundwater.
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高影响因子
ENVIRONMENTAL RESEARCH
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2023
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IF 8.3
Xuefang Zhao,Hui Xu,Minzhang Chen,Yong Chen,Xiuqing Kong
The degradation of organic pollution by sulfur-modified nano zero-valent iron(S-nZVI) combined with advanced oxidation systems has been extensively studied. However, the low utilization of nZVI and low reactive oxygen species (ROS) yield in the system have limited its wide application. Herein, a natural organic acid commonly found in citrus fruits, citric acid (CA), was combined with the conventional S-nZVI@Ps system to enhance the degradation of norfloxacin (NOR). The addition of CA increased the NOR removal by about 31% compared with the conventional S-nZVI@Ps system under the same experimental conditions. Among them, the enhanced effect of CA is mainly reflected in its ability to promote the release of Fe 2+ and accelerate the cycling of Fe 2+ and Fe 3+ to further improve the utilization of nZVI and the generation of ROS; it also promotes the dissolution of the active substance (FeS) on the surface of S-nZVI to further improve the degradation rate of NOR. More importantly, the chelate of CA and Fe 2+ (CA-Fe 2+ ) had higher reactivity than alone Fe 2+ . Free radical quenching and electron spin resonance (ESR) experiments indicated that the main ROS for the degradation of NOR in the CA/S-nZVI@Ps system were SO 4 •- and OH•. CA-bound sulfur-modifying effects on NOR degradation was systematically investigated, and the degradation mechanism of NOR in CA/S-nZVI@Ps system was explored by various techniques. Additionally, the effect of common anions in water matrix on the degradation of NOR in CA/S-nZVI@Ps system and its degradation of various pollutants were also studied. This study provides a new perspective to enhance the degradation of pollutants by S-nZVI combined with advanced oxidation system, which can help to solve the application boundary problem of S-nZVI.
研究领域:
环境科学
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化学工程
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PubMed
高影响因子
WATER RESEARCH
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2022
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IF 13.4
Shuangjie Xiao,Zilan Jin,Haoran Dong,Junyang Xiao,Yangju Li,Long Li,Rui Li,Jie Chen,Ran Tian,Qianqian Xie
There are plentiful ways to synthesize sulfidized nanoscale zerovalent iron (S-nZVI), and this study investigated the influence of sulfur reagents (Na 2 S, Na 2 S 2 O 3 , Na 2 S 2 O 4 ) and sulfidation sequence (co-sulfidation and post-sulfidation method) on the physicochemical properties, reactivity, and long-term performance of S-nZVI in simulated groundwater. The results suggested that the co-sulfidized nZVI (S-nZVI co ) has higher reactivity (∼2-fold) than S-nZVI post due to the stronger electron transfer capacity, deriving from the higher content of Fe 0 and reductive sulfur species. However, during aging, the reactivity of S-nZVI co would be lost more rapidly than S-nZVI post , due to the faster corrosion of Fe 0 and more oxidation of reductive sulfur species. S-nZVI post has the superior long-term performance with the degradation rate of trichloroethylene (TCE) remained at 30%∼60% even after 90 d of aging. Sulfur precursors can control the selectivity of S-nZVI by affecting the sulfur speciation on the particle surface. The proportion of reductive sulfur species on S-nZVI post synthesized by Na 2 S was higher than S-nZVI post synthesized by Na 2 S 2 O 3 or Na 2 S 2 O 4 , resulting in a higher selectivity of the former S-nZVI post than the latter S-nZVI post . In addition, sulfidation procedures and sulfur precursors did not affect the degradation pathway of TCE. Nevertheless, the degradation product distribution can be affected by the different physicochemical transformation of various types of S-nZVI with the aging time. These results indicated that sulfur reagents and sulfidation procedures have crucial effects on the reactivity and long-term performance of S-nZVI, which can be designed for the specific application scenarios.
研究领域:
环境科学
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化学工程
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材料科学
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PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
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2025
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IF 8.4
Xiao-Ming Zou,Tiao Zhang,Yu-Hua Dong,Cui Hu,Li Yin,Yu-Ling Zheng,Mi Li,Xiao-Yu Xiao,Wei Hui
Sulfonamide antibiotics (SAs) are widely used in the biomedical field but pose an environmental risk as ecotoxic pollutants. Developing eco-friendly methods to degrade SAs into harmless compounds is crucial. In this work, biochar (BC) was prepared from rice straw via pyrolysis and used to support S-nZVI, thereby forming the S-nZVI/BC composites. The results show high SAs removal efficiency (up to 98.3%) at optimal Fe/C and Fe/S molar ratios of 3:1 and 50:1, respectively, with strong tolerance to coexisting ions. Furthermore, the effectiveness of S-nZVI/BC(Fe 3 /C 1 , Fe 50 /S 1 ) sample was validated using five real wastewaters, and the results showed consistent performance, stability and reusability. Mechanistic studies revealed that S-nZVI/BC synergized with persulfate to enhance the reactivity of sulfate-free radical (SO 4− ·) and Fe 2+ . The degradation pathways of SAs, involving electrophilic substitution and nucleophilic attack, were elucidated by density functional theory (DFT) calculations. These insights were instrumental in comprehending the degradation mechanism of SAs. Additionally, the degradation dynamics of ten SAs were further analyzed using quantitative structure-activity relationship (QSAR) models and principal component analysis (PCA). Hence, this work highlights the potential of S-nZVI/BC for industrial wastewater treatment, providing insights into the degradation mechanisms and pathways of SAs.
研究领域:
环境科学
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材料科学
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PubMed
高影响因子
Journal of Hydro-environment Research
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2018
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IF 2.087
Pengjun Li,Kairong Lin,Zhanqiang Fang,Wenfeng Zhang
In this study, degradation of nitrate in drinking water by nanoscale zero-valent iron prepared from steel pickling waste liquor(S-NZVI) was investigated. Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM) and Specific Surface Area Analyzer (BET) were used to characterize the properties of the synthesized nanoparticles. Effects of different parameters, such as S-NZVI dosage, initial nitrate concentration, and pH, on the denigration were conducted. The results showed that S-NZVI had the similar characteristic of the NZVI prepared by chemical agents. The experiments indicated that the slightly acid medium with the S-NZVI dosage of 2.8 g/L had a better removal effect of nitrate, and the high removal efficiency of 96% was observed after the reaction time of 2 h, which demonstrated it was feasible and effective to remove nitrate by S-NZVI. The kinetic studies indicated that the degradation rate of nitrate by S-NZVI followed the pseudo-first order kinetics. By analyzing the end-products of nitrate reduction, 94% of nitrate was converted into ammonia ions by S-NZVI and the others translated into a little amount of nitrite and nitrogen. It is a relatively easy and cost-effective method for nitrate removal, so S-NZVI has a great potential application in nitrate removal of drinking water. The ammoniac nitrogen pollution, the main product and second pollution from the denitrification by S-NZVI can be completely degraded by cation exchange resin. So the nitrogen pollution has been completely removed from drinking water polluted by nitrate.
研究领域:
环境科学
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水处理工程
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高影响因子
Environmental Science-Water Research & Technology
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2022
·Vol. 8
·期 11
·2567-2579
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IF 5.819
Fang Cheng,Jun Hou,Jun Wu,Yi Xu,Lingzhan Miao,Jun Xia,Zongli Huo
pentachlorophenol (PCP) is a kind of chlorinated aromatic contaminant that brings challenges from an environmental perspective. However, the performance of sulfidated nanoscale zero-valent iron (S-nZVI) in PCP removal remains unknown. In this study, S-nZVI was applied in the treatment of PCP-polluted water under different water chemistry conditions. The results showed that PCP was removed under the combined action of adsorption, dechlorination, and ˙OH-mediated oxidation, among which dechlorination played a leading role while oxidation lagged behind. The amount of adsorbed PCP correlated well with the PCP dechlorination rate constant (kred), except for S/Fe 0 and 0.1 and acidic initial pH (pHinitial) conditions. At neutral and alkaline pHinitial, kred increased with an increase in pHinitial due to the formation of a hydroxide layer that facilitates adsorption. At acidic pHinitial, kred increased with a decrease in pHinitial because hydrogen ions diffusing in the solution participated in the reaction. The effects of solution chemistry, such as anions, organic matter, and oxygen conditions, on PCP adsorption and transformation were also studied. Eight degradation byproducts were observed; the dechlorination products suggested that PCP dechlorination by S-nZVI occurred via a sequential pathway. PCP and its dechlorination products would then undergo ˙OH-mediated oxidation, resulting in products that are beneficial for microbes. Changes to S-nZVI after reacting and the role of sulfur were also discussed. This study confirmed that S-nZVI can be effective in the remediation of PCP-polluted groundwater. Further research is needed to optimize this remediation via coupling microbial technology and controlling the oxygen conditions.
研究领域:
环境科学
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化学
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高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2021
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IF 10.588
Yibo Yuan,Xipeng Wei,Hua Yin,Minghan Zhu,Haoyu Luo,Zhi Dang
The effects of organic acids on hexavalent chromium (Cr(VI)) removal by reduced iron-based materials have been extensively studied. Nevertheless, the promotion mechanism from the perspective of the electron transfer process is still unclear. Herein, sulfidated nanoscale zero-valent iron (S-nZVI) and the selected organic acids, citric acid (containing both -OH and −COOH groups) and oxalic acid (containing only −COOH groups), showed significant synergistic promotion effects in Cr(VI) removal. The FeS and FeS 2 on S-nZVI surface could enhance the Cr(VI) reduction as the reductive entity and electron conductor. Furthermore, even though the reactivity of FeS with Cr(VI) is higher than that with FeS 2 , the Cr(VI) removal efficiency by FeS 2 was much higher than that by FeS with organic acids. Under neutral and alkaline conditions (pH 6.0–8.0), organic acids promoted the diffusion, adsorption and complexation of Cr(VI) on S-nZVI surface, thus enhancing the electron selectivity towards Cr(VI). However, when the solution pH changed to acidic conditions (pH 4.0), organic acids facilitated the dissolution of Fe(II) ions from S-nZVI and enhanced the electron utilization towards Cr(VI) via the fast Fe(III) reduction process. This study provided a new insight into the Cr(VI) removal, which was beneficial to understand the application boundaries of S-nZVI for Cr(VI) remediation.
研究领域:
环境科学
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化学
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PubMed
高影响因子
危险品化学品经营许可证（带存储）