摘要
针对硫化纳米零价铁(Fe/FeS)颗粒间的团聚以及环境适应性差的问题,用正硅酸乙酯(TEOS)为原料制备中空介孔氧化硅球,再通过化学反应在壳内形成大尺寸核的方法制备具有蛋黄-蛋壳结构的Fe/FeS@SiO^2材料以防止Fe/FeS的团聚并提高其活性,并将该材料用于三氯乙烯(TCE)的去除中;采用SEM和TEM观察、红外线光谱分析(FTIR)、X射线衍射分析(XRD)、X射线光电子能谱分析(XPS)等分析方法对材料进行了表征。结果表明,在Fe/FeS@SiO^2材料还原降解TCE的实验中,Fe/FeS@SiO^2去除TCE的最佳铁与硫的摩尔比(铁硫比)为30,并且在TCE初始浓度10 mg·L^-1溶液中投加含有0.1 g Fe^0、铁硫比为30的Fe/FeS@SiO^2材料下,反应180 min后,TCE的去除率为90.75%,与未包裹氧化硅壳时的去除率(66.06%)相比,去除效果明显提高。介孔氧化硅壳阻止了Fe/FeS的团聚,其表面上的孔道使得材料具有更大的比表面积,加强了对TCE的吸附,同时材料中的空腔使得核与污染物的接触增加,提高了TCE的去除率。表征结果表明,Fe/FeS@SiO^2材料具有特殊的结构,包括中心核、空腔以及介孔壳,可以防止Fe/FeS的团聚。
Aiming at the agglomeration of sulfurized nano-zero-valent iron(Fe/FeS)due to its interaction between particles and poor environmental adaptability,the hollow mesoporous silica spheres were prepared by using tetraethyl orthosilicate(TEOS)as the silicon source,and then the Fe/FeS@SiO^2 material with yolk-shell structure was prepared by"ship-in-a-bottle"method to prevent the agglomeration of Fe/FeS and improve its activity,which was used to remove trichloroethylene(TCE).Scanning electron microscopy(SEM),transmission electron microscopy(TEM),Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction analysis(XRD)and X-ray photoelectron spectroscopy(XPS)were employed to characterize above materials.The characterization results revealled that the Fe/FeS@SiO^2 yolk-shell particles had special structures,including active cores,mesoporous shells and hollow cavities,which could prevent the agglomeration of Fe/FeS.The experimental results showed that the optimum mass ratio of Fe to S for Fe/FeS@SiO^2 preparation was 30.At TCE initial concentration of 10 mg·L^-1,Fe dosage of 0.1 g and reaction time of 180 min,the TCE removal efficiency reached 90.75%,which was significantly higher than that of Fe/FeS(66.06%).The mesoporous silica shell inhibited the agglomeration of Fe/FeS,and the pores in the shell provide a larger specific surface area for the Fe/FeS@SiO^2 yolk-shell particles,which enhances the TCE adsorption.Moreover,the cavity in the material could strengthen the contact between the cores and the contaminants,which improved the TCE removal efficiency.
作者
任路遥
陈帅
刘勇弟
李辉
REN Luyao;CHEN Shuai;LIU Yongdi;LI Hui(State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process,School of Resources and Environmental Engineering,East China University of Science and Technology,Shanghai 200237,China;Research Center of Resource Recycling Science and Engineering,School of Environmental and Materials Engineering,Shanghai Polytechnic University,Shanghai 201209,China;Institute for Environmental Pollution and Health,School of Environmental and Chemical Engineering,Shanghai University,Shanghai 200444,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2019年第11期2537-2544,共8页
Chinese Journal of Environmental Engineering
基金
上海市学术/技术研究带头人项目(18XD1424100)
中国环境科学研究院环境基准与风险评估国家重点实验室开放基金(SKLECRA2016OFP19)
霍英东教育基金会(141077)
上海市教委创新计划(14ZZ059)
国家自然科学基金资助项目(41877377,51578240).
