COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2019
·
IF 3.131
Zongtang Liu,Congcong Ding,Pingting Gao,Yunxia Xu,Yufeng Sun,Xiaoju Wen,Jingtao Dai,Zhenghao Fei
For the first time, the dechlorination of 2,6-dichlorophenol (2,6-DCP) by carbon nanotubes supported Fe/Ni nanoparticles (CNTs-Fe/Ni) was studied to explore the practicability of environmental remediation. Removal capacity of CNTs-Fe/Ni for 2,6-DCP was enhanced obviously compared to Fe/Ni due to reduced aggregation of Fe/Ni nanoparticles .The removal efficiency increased as the increase of CNTs-Fe/Ni dosage and Ni loading, whereas it decreased as the increase of 2,6-DCP concentration. Weak acidic condition was considered to be advantageous to 2,6-DCP dechlorination. The dechlorination kinetics results suggested that the 2,6-DCP removal by CNTs-Fe/Ni accorded with pseudo-first-order equation. Moreover, carbon nanotubes as support accelerated the mass transfer of 2,6-DCP from solution to catalyst surface and promoted the formation of atomic hydrogen, which also led to an enhancement of reactivity of CNTs-Fe/Ni on removing 2,6-DCP.
研究领域:
环境科学
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纳米技术
·
化学工程
✓ 已验证
DOI
高影响因子
WATER RESEARCH
·
2025
·
IF 12.4
Shichao Cai,Yurou Tan,Hongyi Li,Bo Chen,Feng He
Sulfidated microscale zero-valent iron (S-mZVI) is a promising ZVI material for remediation of chlorinated hydrocarbons (CHCs). However, the structure and dechlorination behavior change of S-mZVI induced by sulfophilic metal (Me) ions in groundwater are barely studied. Here we show that Me ion-amended S-mZVI (S-mZVI Me ) have a rate sequence of S-mZVI Co >S-mZVI Ni >S-mZVI>S-mZVI Cu >S-mZVI Cd ≈ S-mZVI Zn and S-mZVI Ni >S-mZVI Cd >S-mZVI ≈ S-mZVI Zn ≈ S-mZVI Cu ≈ S-mZVI Co for trichlorethylene (TCE) dechlorination and hydrogen evolution reaction (HER), respectively. This results in the highest ever reported electron efficiency (98.6%) for TCE dechlorination by S-mZVI Co . Cross-section SEM-EDS, XRD, and XPS analyses confirm the formation of MeS x on the surface of all S-mZVI Me . Additionally, Ni 0 , Cu 0 , and possibly Cd° formed on the S-mZVI Ni , S-mZVI Cu , and S-mZVI Cd , respectively. Theoretical calculations indicate that the nascent metal sulfides are more hydrophobic than FeS, indicating the faster HER with Ni and Cd amendment is likely due to formation of bimetallic structures. Correlation analyses suggest that both low band gap and high work function of the semi-conductive Co sulfide contribute to the high reactivity of S-mZVI Co . Column studies further show that implementing Co 2+ enables the dechlorination of TCE from 2000 µg/L to < 70 µg/L up to 1000 pore volumes by S-mZVI, compared to > 1.2 mg/L without Co 2+ . These findings have important implications for remediation of CHC-contaminated sites using S-mZVI.
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
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2018
·
IF 6.653
Shaodong Hou,Li Ling,Dionysios D. Dionysiou,Yuru Wang,Jiajia Huang,Kaiheng Guo,Xuchun Li,Jingyun Fang
Halides and natural organic matter (NOM) are inevitable in aquatic environment and influence the degradation of contaminants in sulfate radical (SO4•–)-based advanced oxidation processes. This study investigated the formation of chlorate in the coexposure of SO4•–, chloride (Cl–), bromide (Br–) and/or NOM in UV/persulfate (UV/PDS) and cobalt(II)/peroxymonosulfate (Co/PMS) systems. The formation of chlorate increased with increasing Cl– concentration in the UV/PDS system, however, in the Co/PMS system, it initially increased and then decreased. The chlorate formation involved the formation of hypochlorous acid/hypochlorite (HOCl/OCl–) as an intermediate in both systems. The formation was primarily attributable to SO4•– in the UV/PDS system, whereas Co(III) played a significant role in the oxidation of Cl– to HOCl/OCl– and SO4•– was important for the oxidation of HOCl/OCl– to chlorate in the Co/PMS system. The pseudo-first-order rate constants (k′) of the transformation from Cl– to HOCl/OCl– were 3.32 × 10–6 s–1 and 9.23 × 10–3 s–1 in UV/PDS and Co/PMS, respectively. Meanwhile, k′ of HOCl/OCl– to chlorate in UV/PDS and Co/PMS were 2.43 × 10–3 s–1 and 2.70 × 10–4 s–1, respectively. Br– completely inhibited the chlorate formation in UV/PDS, but inhibited it by 45.2% in Co/PMS. The k′ of SO4•– reacting with Br– to form hypobromous acid/hypobromite (HOBr/OBr–) was calculated to be 378 times higher than that of Cl– to HOCl/OCl–, but the k′ of Co(III) reacting with Br– to form HOBr/OBr– was comparable to that of Cl– to HOCl/OCl–. NOM also significantly inhibited the chlorate formation, due to the consumption of SO4•– and reactive chlorine species (RCS, such as Cl·, ClO· and HOCl/OCl–). This study demonstrated the formation of chlorate in SO4•–-based AOPs, which should to be considered in their application in water treatment.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Xuan Zhang,Siyu Xu,Yawei Gu,Ling Zhang,Longquan Zhang,Fengxu Shang,Xinze Song,Zhen Wang,Xiaoguo Shi,Honglei Zhang,Runze Bi,Jinbo Chen
Zero-valent iron (ZVI) technology has become prevalent for the in situ dechlorination of trichloroethylene (TCE) widely found in soils and groundwater. Nevertheless, ZVI technology still encounters several severe bottlenecks, including inadequate reactivity, poor selectivity, and unelucidated mechanism. Herein, we report that a C&S-mZVI bm material, with the Co-incorporation of C and S into Zero-Valent Iron, could significantly improve the degradation efficiency of ZVI, while simultaneously inhibiting the hydrogen evolution reaction (HER), thereby enhancing the electron selectivity in the TCE dechlorination. Comprehensive characterization techniques have demonstrated that the Co-incorporation of C and S into ZVI leads to better TCE affinity, faster electron transfer and lower charge-transfer resistances. In addition, novel FeS x and Fe 3 C species emerged as new active sites, resulting in two distinct reaction pathways. Specifically, when the C weight percentage is below 2 %, the cumulative quantity of hydrocarbon products surpasses that of DCE, indicating the dominant β-elimination pathway. Conversely, when the weight percentage of C exceeds 2 %, the overall hydrocarbon products fall short of DCE, suggesting that the TCE hydrogenolysis dechlorination reaction becomes the primary pathway. These insights can benefit not only the development of ZVI-based materials but also enhance the broad application of these materials in remediation of groundwater with chlorinated hydrocarbons.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2024
·
IF 12.2
Si-Ying Yang,Chun-Yu Lai,He-Ping Zhao
In situ remediation of low-permeability soils contaminated with trichloroethylene (TCE) is challenging due to limited mass transfer and low bioavailability in clay soils. The electrokinetic-enhanced bioremediation (EK-BIO) system offers a promising solution by combining electrokinetics with bioremediation to address these challenges. While previous studies have demonstrated microbial succession and TCE removal, the long-term performance of dechlorination and interactions between electrode reactions and anaerobic dechlorination remain unclear. This study constructed five one-dimensional columns, each operated for a different period (28, 42, 56, 84 and 138 days) to explore spatial and temporal dechlorination patterns. Continuous TCE degradation was achieved, with 46.52 % of TCE recovery. Prolonged electrokinetic operation accelerated the first-step dehalogenation (TCE to DCE). Although Dehalococcoides was widespread at 138 days (2.30–5.74 %), oxygen exposure led to irreversible damage, necessitating secondary inoculation. The presence of aerobic bacteria ( Comamonas and Pseudomonas ) suggested the formation of aerobic detoxification pathways in electrode chambers. Gene expression analysis ( tceA , vcrA and Dhc16S ) further confirmed the loss of 2nd and 3rd step dehalogenation (DCE to ethene) over time. These findings demonstrate that secondary inoculation and alternative aerobic pathways can sustain long-term biodegradation in the EK-BIO system. This study highlights the potential of the EK-BIO system for effective remediation of TCE-contaminated low-permeability soils, supporting its field application.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2025
·
IF 0
Liu Pengxiao,Gao Shuai,Li Ying,Hou Bin,Liu Ning,Du Zhen,Lu Jing
This study investigated the aging and pollution behavior of acrylonitrile butadiene styrene (ABS) and polycarbonate (PC) microplastics (MPs) exposed to residual chlorine in tap water distribution systems. The ABS and PC MPs in the aging processes were analyzed using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Results revealed that 0.4 mg/L residual chlorine could induce morphological changes, increase surface oxygen-containing functional groups, and enhance the hydrophilicity of MPs at the CT value of 9216 mg·min/L. Additionally, both ABS and PC MPs released dissolved organic matter (DOM) into water, with higher DOM concentrations observed in the presence of residual chlorine. Besides, this interaction also led to the formation of trichloromethane (TCM). And the TCM production increased with higher MPs concentrations, smaller particle size, and longer chlorine exposure time.
研究领域:
环境科学
·
污染生态学
✓ 已验证
产品关联
DOI
PubMed
MARINE POLLUTION BULLETIN
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2025
·
IF 4.9
Jingwei Wang,Pan Zhao,Jiaxin Wang,Shuzhen Li,Qiao Ma
Triclocarban (TCC) and triclosan (TCS) are applied in a wide range of pharmaceutical and personal care products to prevent or reduce bacterial growth. Due to their extensive application, they are frequently detected in marine environments. In this study, marine sediment systems exposed to different concentrations of TCC and TCS were established to evaluate their effects on microbial communities. It was found that TCC and TCS increased catalase and protease activities on Day 1, but inhibited after 15 days. Microbial activity, as indicated by increased dehydrogenase activity and polysaccharide production, should be enhanced after a 15-day adaptation period. High-throughput sequencing revealed resilient α-diversity but significant shifts in community structures were observed, particularly on Day 15. Function prediction analysis confirmed that most functional profiles remained stable, and network analysis indicated that TCC and TCS enhanced the complexity of the microbial community. This study provides new insights into the impacts and risks of TCC and TCS on the marine environment.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Yijiang Li,Chen Chen,Wencheng Xia,Yujin Sun,Hongxin Qiu
In this study, in-situ flocculation kinetics tests, fourier transform infrared spectroscopy and DFT theoretical calculation were used to analyze flocs properties of calcite flocs under combination of sodium alginate and AlCl 3 /polyaluminum chloride (PAC) and their adsorption mechanism. The results showed that the average size of calcite flocs treated with AlCl 3 -sodium alginate was smaller than that of flocs treated with PAC-sodium alginate. The number of residual fine particles in the slurry treated with AlCl 3 -sodium alginate was more than that in the slurry treated with PAC-sodium alginate. However, the fractal dimension of calcite flocs treated with AlCl 3 -sodium alginate was larger than those treated with PAC-sodium alginate. The sodium alginate and Al 3+ could form chemical adsorption on the calcite surface. AlCl 3 has a higher content of Ala than PAC. Ala could form chemical adsorption between sodium alginate and calcite, resulting in a high strength and fractal dimension of calcite flocs. Alb and Alc was not easily able to form metal bridges between calcite and sodium alginate. The sweep effect of PAC and sodium alginate leads to the formation of large-sized flocs. This work can promote the supplication of sodium alginate as a green flocculant.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
·
IF 9.038
Yichen Zhen,Qiang Zhang,Xiaoyan Zhang,Guanteng Zhang,Xiaoxin Chen,Chunxia Zhao
Chlorophenols (CPs) are still used as raw material or intermediate in some industries. Photocatalytic oxidation is free from secondary pollution, but the efficiency is restricted by some main factors. In this study, a novel high efficiency tubular up-flow magnetic film (TUMF) photocatalytic system was investigated based on the magnetic lanthanum doping core-shell Fe 3 O 4 @SiO 2 @TiO 2 (La-FST) nanoparticles. When the dosage of La-FST was 0.4 g/L, the flow velocity was 94.2 mL/min, and the circulated irradiation of 15 W maintained 40 min, the average removal rate of 2,4-dichlorophenol (2,4-DCP) was reduced significantly from 10 mg/L to 0.0803 mg/L by TUMF system, meeting the limits of the particular items (0.093 mg/L) from national environmental quality standards for surface water, avoiding the problem of photocatalyst separation and loss. The photoinduced holes ( h + ) was the key active radical to oxidize 2,4-DCP, and the main factors of TUMF system could be well controlled to achieve satisfactory effluent quality. A prediction method of photocatalytic reaction time in a multistage series TUMF system was established to remove 2,4-DCP from 100 mg/L to 0.5 mg/L, saving 86 min. The novel high-efficiency TUMF system provides a technical selection for the photocatalytic degradation of CPs and other refractory organics.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Chemical Engineering and Processing-Process Intensification
·
2024
·
IF 3.8
Zifei Yan,Grace Dai Zhen Lee,Jian Deng,Guangsheng Luo
The synthesis of terminal epoxides, which are vital components in pharmaceuticals and resins, often involves dehydrochlorination of β-chlorohydrins. Although intrinsic kinetics indicate that the dehydrochlorination reaction in the presence of sodium hydroxide could be very rapid, the practical implementation could always be hindered by long reaction time and low conversion rate. Extended contact between the product and the alkaline solution can lead to hydrolysis of the epoxy group, thus necessitating the process intensification to realize higher production efficiency and selectivity. Here, by characterizing thermodynamic equilibrium data and in-situ recording of the reaction that proceeded in a constant interphase reactor, the heterogeneous dehydrochlorination is demonstrated to occur primarily in the organic phase, and the overall reaction rate depends on the equilibrium concentration of sodium alkoxides. This finding, which is fundamentally different from the traditional view that chlorohydrin is first dissolved in the aqueous phase and then reacts with NaOH, leads us to use inert alcohols to assist in the extraction of NaOH. Based on this method, the reaction time can be reduced over 80 % both in batch and continuous reactors. Besides, the method is demonstrated to be effective in the dehydrochlorination of five different long-chain β-chlorohydrins.
研究领域:
化学工程
·
有机合成
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2020
·
IF 5.006
Haodong Duan,Xiaolei Xu,Kangwei Leng,Ge Guo,Qing Yu,Xinjin Li,Yuxi Han,Jun Gao,Zhongwei Wang
The characteristics of the reaction for the preparation of dichlorophenylphosphine (DCPP) via benzene and PCl 3 in the presence of AlCl 3 were studied. Some unique characteristics were observed when a catalytic amount of AlCl 3 was used. Namely, more than one mole of DCPP was obtained per mole AlCl 3 , the reaction solution was layered, and DCPP could be directly separated. Our mechanistic study showed that benzene reacted with PCl 3 to form DCPP-AlCl 3 , and DCPP-AlCl 3 dissociated into DCPP and AlCl 3 , continuing to catalyze this reaction. This resulted in the high catalytic efficiency of AlCl 3 . The layering of the reaction solution was caused by the immiscibility of DCPP-AlCl 3 with the raw materials, greatly facilitating the dissociation process of DCPP-AlCl 3 . The formation of diphenylphosphorus chloride (DPC) was due to a continuous Friedel-Crafts reaction between DCPP and benzene. DPC cooperated with AlCl 3 to form the stable coordination compound DPC-AlCl 3 that did not dissociate and was responsible for the deactivation of AlCl 3 .
研究领域:
有机化学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2020
·
IF 9.038
Xiaoxiao Zhang,Zhonglin Chen,Jing Kang,Shengxin Zhao,Binyuan Wang,Pengwei Yan,Fengxia Deng,Jimin Shen,Wei Chu
In this study, kinetics, influencing factors and potential mechanisms involved in the degradation of chloral hydrate (CH) by UV/peroxymonosulfate (PMS) process were demonstrated. The degradation rate of CH could reach 89.6% by UV 254 /PMS process, significantly exceeding UV 300 /PMS (0.7%), UV 350 /PMS (6.3%), UV 254 direct photolysis (9.0%) and PMS alone (0.0%) processes. CH degradation in UV 254 /PMS system followed pseudo first-order degradation kinetics with an apparent rate constant of 0.186 min −1 , which was suppressed by Cl − and HCO 3 − . The optimal pH for CH degradation was around 5.0. Direct mineralization accounted for the CH degradation in UV/PMS system. Interestingly, the addition of PMS at the neutral condition before UV irradiation transferred CH into trichloroacetic acid (TCAA). The transformation efficiency of CH into TCAA at 10 min was enhanced from 2.17%–40.38% with the elevation of initial pH from 7.0–8.0. The subsequent exposure of UV lamps ceased the transformation of CH into TCAA and facilitated the direct mineralization of CH, but it did not work in the refractory TCAA degradation. Finally, it was revealed that HO predominantly participated CH degradation in UV/PMS process, while O 2 − was responsible for the transformation of CH into TCAA by addition of PMS before UV irradiation.
研究领域:
环境科学
·
化学工程
✓ 已验证
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）