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Reductive dechlorination of 2,4-dichlorophenol using nanoscale Fe^0: influencing factors and possible mechanism

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Science China Chemistry 2007年第4期50卷 574-579页

作者： CHENG Rong WANG JianLong zhang weixian Laboratory of Environmental Technology INETTsinghua UniversityBeijing 100084China Department of Civil and Environmental Engineering Lehigh UniversityBethlehemPA 18015-3176USA

Nanoscale Fe0 was synthesized through a reductive method in this paper. The experiments were per-formed to investigate the reduction of 2,4-dichlorophenol (2,4-DCP) by nanoscale Fe0 under different conditions. The pathways for the reduction of 2,4-DCP by nanoscale Fe0 were discussed. Batch studies demonstrated that the mechanism includes adsorption, dechlorination and cleavage of the benzene ring. Dechlorination, which occurs after 2,4-DCP molecule is adsorbed on the interface of Fe particle, is an interfacial reaction. One or two chlorine atom can be removed from 2,4-DCP to form 2-chlorophenol, 4-chlorophenol or phenol. As the concentration of 2,4-DCP increased, the relative dechlorination ratio decreased. However, the reduced quantities of 2,4-DCP increased. Temperature can influence dechlo-rination rate and pathway. Dechlorination is prior to cleavage of the benzene ring at a higher tempera-ture, but at a lower temperature, adsorption may be the main pathway, and cleavage of the benzene ring may be prior to dechlorination.

关键词： nanoscale Fe^0 2 4-DCP adsorption dechlorination cleavage of the benzene ring

Degradation of chlorinated phenols by nanoscale zero-valent iron

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Frontiers of Environmental Science & Engineering 2008年第1期2卷 103-108页

作者： Rong CHENG Jianlong WANG weixian zhang Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Department of Civil and Environmental Engineering Lehigh UniversityBethlehemPA 18015-3176USA

Chlorophenols(CPs),as important contami-nants in groundwater,are toxic and difficult to ***-valentironreceivedagreat deal of attention because of its excellent performance in treating recalcitrant *** this study,nanoscale zero-valent iron particles were prepared using chemical reduction,and the reductive transformations of three kinds of chlorinated phenols(2-CP,3-CP,and 4-CP)by nanoscale zero-valent iron under different conditions were *** transformation process of the CPs was shown to be dechlorination first,then cleavage of the benzene *** removal efficiency of the CPs varied as follows:*** reactivity of CPs was associated with their energy of lowest unoccupied molecular orbit(E LUMO).With the increase in initial concentrations of CPs,removal efficiency decreased a *** the quantities of CPs reduced increased *** had influence on not only the removal efficiency,but also the transformation *** higher temperatures,dechlorination occurred prior to benzene ring *** lower temperatures,however,the oxidation product was formed more easily.

关键词： nanoscale zero-valent iron chlorophenol dechlorination molecular orbit theory

Optimizing synthesis conditions of nanoscale zero-valent iron （nZVI） through aqueous reactivity assessment

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Frontiers of Environmental Science & Engineering 2015年第5期9卷 813-822页

作者： Yanlai HAN Michael D. Y. YANG weixian zhang Weile YAN Department of Civil and Environmental Engineering Texas Tech University Lubbock TX 79409 USA State Key Laboratory for Pollution Control & Resources Reuse Tongji University Shanghai 200092 China

Nanoscale iron particles （nZVI） is one of the most important engineered nanomaterials applied to environmental pollution control and abatement. Although a multitude of synthesis approaches have been proposed, a facile method to screen the reactivity of candidate nZVI materials produced using different methods or under varying synthesis conditions has yet been established. In this study, four reaction parameters were adjusted in the preparation of borohydride-reduced nZVI. The reductive properties of the resultant nanoparticles were assayed independently using two model aqueous contaminants, Cu （II） and nitrate. The results confirm that the reductive reactivity of nZVI is most sensitive to the initial concentration of iron precursor, borohydride feed rate, and the loading ratio of borohydride to ferric ion during particle synthesis. Solution mixing speed, in contrast, carries a relative small weight on the reactivity of nZVI. The two probing reactions （i.e., Cu（II） and nitrate reduction） are able to generate consistent and quantitative inference about the mass-normalized surface activity of nZVI. However, the nitrate assay is valid in dilute aqueous solutions only （50 mg.L~ or lower） due to accelerated deactivation of iron surface at elevated nitrate concentra- tions. Additional insights including the structural and chemical makeup of nZVI can be garnered from Cu（II） reduction assessments. The reactivity assays investigated in this study can facilitate screening of candidate materials or optimization of nZVI production parameters, which complement some of the more sophisticated but less chemically specific material characterization methods used in the nZVI research.

关键词： iron nanoparticles nanoscale iron particles(nZVI) synthesis characterization Cu(II) reduction nitratereduction

Microbial fuel cell with high content solid wastes as substrates： a review

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Frontiers of Environmental Science & Engineering 2017年第2期11卷 25-41页

作者： Qingliang Zhao Hang Yu weixian zhang Felix Tetteh Kabutey Junqiu Jiang Yunshu zhang Kun Wang Jing Ding State Key Laboratory of Urban Water Resources and Environments (SKLURE) Harbin Institute of Technology Harbin 150090 China Shanghai Municipal Engineering Design Institute (Group) Co. Ltd. Shanghai 200092 China

With the increasing concern about the serious global energy crisis and high energy consumption during high content solid wastes （HCSWs） treatment, microbial fuel cell （MFC） has been recognized as a promising resource utilization approach for HCSW stabilization with simultaneous electrical energy recovery. In contrast to the conventional HCSW stabilization processes, MFC has its unique advantages such as direct bio-energy conversion in a single step and mild reaction conditions （viz., ambient temperature, normal pressure, and neutral pH）. This review mainly introduces some important aspects of electricity generation from HCSW and its stabilization in MFC, focusing on：（1） MFCs with different fundamentals and configurations designed and constructed to produce electricity from HCSW; （2） performance of wastes degradation and electricity generation; （3） prospect and deficiency posed by MFCs with HCSWas substrates. To date, the major drawback of MFCs fueled by HCSW is the lower power output than those using simple substrates. HCSW hydrolysis and decomposition would be a major tool to improve the performance of MFCs. The optimization of parameters is needed to push the progress of MFCs with HCSW as fuel.

关键词： Microbial fuel cellHigh content solid wastesSubstrateBioremediationBiosensor

Monodisperse core-shell structured magnetic mesoporous aluminosilicate nanospheres with large dendritic mesochannels

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Nano Research 2015年第8期8卷 2503-2514页

作者： Jianping Yang Dengke Shen Yong Wei Wei Li Fan zhang Biao Kong Shaohua zhang Wei Teng Jianwei Fan weixian zhang Shixue Dou Dongyuan Zhao College of Environmental Science and Engineering State Key Laboratory of Pollution Control and Resources Reuse Tongji University Shanghai 200092 China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysis and Laboratory of Advanced Materials Fudan University Shanghai 200433 China Institute for Superconducting & Electronic Materials Australian Institute of Innovative Materials University of Wollongong Innovation Campus Squires Way North Wollongong NSW 2500 Australia Key Laboratory of Materials Physics Centre for Environmental and Energy Nanomaterials Anhui Key Laboratory of Nanomaterials and Nanotechnology Institute of Solid State Physics Hefei Institutes of Physical Science Chinese Academy of Sciences Hefei 230031 China

The rational design and precise synthesis of multifunctional hybrid nanostructures with a tailored active core and a large, dendritic, modified mesoporous structured shell can promote catalysis, energy storage, and biological applications. Here, an oil-water biphase stratification coating strategy has been developed to prepare monodisperse magnetic dendritic mesoporous silica core-shell structured nano- spheres. These sophisticated Fe3O4@SiO2@dendritic-mSiO2 nanospheres feature large dendritic open pores （2.7 and 10.3 nm）. Significantly, the silica shells can be converted into dendritic mesoporous aluminosilicate frameworks with unchanged porosity, a Si/Al molar ratio of 14, and remarkably strong acidic sites, through a post-synthesis approach. In addition, the resultant magnetic dendritic mesoporous aluminosilicate nanospheres exhibit outstanding properties and promising application in phosphate removal from wastewater.

关键词： mesoporous materials core-shell structures aluminosilicates magnetic property surface acid

Transformation of erythromycin during secondary effluent soil aquifer recharging:Removal contribution and degradation path

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Journal of Environmental Sciences 2017年第1期29卷 173-180页

作者： Liangliang Wei Kena Qin Ningbo Zhao Daniel R.Noguera Wei Qiu Qingliang Zhao Xiangjuan Kong weixian zhang Felix Tetteh Kabutey School of Municipal&Environmental Engineering State Key Laboratory of Urban Water Resources and Environment(SKLUWRE)Harbin Institute of TechnologyHarbin 150090China Department of-Civil and Environmental Engineering University of Wisconsin-MadisonMadisonWI 53706USA Center of Science&Technology of Construction of the Ministry of Housing and Urban Rural Development of P.R.China Beijing 100835China

Erythromycin（ERY）,a widely used antibiotic,has recently been detected in municipal secondary effluents and poses serious threats to human health during wastewater *** this study,the removal,fate,and degradation pathway of ERY in secondary effluent during soil aquifer treatment was evaluated via laboratory-scale SAT *** to a 92.9%reduction of ERY in synthetic secondary effluent was observed in 1.0 m depth column system,which decreased to 64.7%when recharged with wastewater treatment plant secondary ***-fractionation results demonstrated that the transphilic acid and hydrophobic acid fractions in secondary effluent compete for the adsorption sites of the packed soil and lead to a declined ERY ***,aerobic biodegradation was the predominant role for ERY removal,contributing more than 60%reduction of ERY when recharged with synthetic secondary *** of 14-member macrocyclic lactone ring and breakdown of two cyclic sugars（L-cladinose and D-desosamine） were main removal pathways for ERY degradation,and produced six new intermediates.

关键词： Erythromycin Soil aquifer treatment Fate Degradation pathway DOM

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铁环境化学——环境和地球化学的研究热点

化学学报 2017年第6期75卷 519-520页

作者：张礼知张伟贤华中师范大学同济大学

铁是地壳元素中丰度第四的过渡金属元素,广泛存在于大气气溶胶、天然水体、土壤和动植物体内.更为重要的是,铁易发生氧化还原反应,在生物地球化学循环过程中扮演着极其重要的角色.此外,铁拥有π特征的d轨道电子使其很容易与C、O、N和S... 详细信息

铁是地壳元素中丰度第四的过渡金属元素,广泛存在于大气气溶胶、天然水体、土壤和动植物体内.更为重要的是,铁易发生氧化还原反应,在生物地球化学循环过程中扮演着极其重要的角色.此外,铁拥有π特征的d轨道电子使其很容易与C、O、N和S等元素形成配合物,是绝大多数生物的电子供体或电子受体.

关键词：环境化学大气气溶胶氧化还原电子受体零价铁天然水体电子供体生物利用度动植物体重金属去除

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纳米金属铁降解有机卤化物的研究进展

化学进展 2006年第1期18卷 93-99页

作者：程荣王建龙张伟贤清华大学核能与新能源技术研究院环境技术研究室北京100084 Department of Civil and Environmental Engineering Lehigh University Bethlehem

有机卤化物是一种毒性强、难生物降解的环境污染物,传统处理技术存在着降解不完全、效率低等不足。纳米技术的发展给有机卤化物的处理带来了一种新的颇具潜力的方法,即应用纳米金属/双金属颗粒对有机卤化物进行脱卤。目前,以Fe(Ⅱ)和Fe(... 详细信息

有机卤化物是一种毒性强、难生物降解的环境污染物,传统处理技术存在着降解不完全、效率低等不足。纳米技术的发展给有机卤化物的处理带来了一种新的颇具潜力的方法,即应用纳米金属/双金属颗粒对有机卤化物进行脱卤。目前,以Fe(Ⅱ)和Fe(Ⅲ)等常见原料合成纳米铁颗粒的技术已经成熟,纳米颗粒对有机卤化物也显示出高效的降解性能。更重要的是,其可灵活应用于地下水和土壤的原位和异位修复,尤其适用于原位修复。本文综述了纳米铁颗粒降解有机卤化物的研究进展,包括纳米铁颗粒的合成与修饰,降解效能、降解机理、降解动力学、示范工程等,以及发展前景和今后的研究方向。

关键词：纳米颗粒有机卤化物铁双金属

Receding Horizon Defense Strategy for Reach-Avoid Games with Uncertainties via Pairwise Outcomes

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Receding Horizon Defense Strategy for Reach-Avoid Games with...