纳米零价铁对钨离子的吸附相平衡和动力学  

Adsorption equilibrium and kinetics of tungsten on nano zero-valent ions

作　　者：赵长多 吴凡 杨晓博[1] 范美玲[1] 夏启斌[1] ZHAO Changduo;WU Fan;YANG Xiaobo;FAN Meiling;XIA Qibin(School of Chemistry and Chemical Engineering,South China University of Technology,Guangzhou 510640,China;Kenchuang Environmental Technology Company of Jiangsu,Changzhou 213161,China)

机构地区：[1]华南理工大学化学与化工学院,广州510640 [2]江苏肯创环境科技股份有限公司,江苏常州213161

出　　处：《功能材料》2018年第7期7144-7150,共7页Journal of Functional Materials

基　　金：广东省科技计划资助项目(2017A020216016);广州市民生科技攻关计划资助项目(201803030012)

摘　　要：采用液相还原法制备纳米零价铁(nZVI),并用PXRD、TEM、BET和XPS等表征手段对材料进行表征。探讨了初始钨(Ⅵ)浓度、纳米零价铁用量和初始pH值对纳米零价铁吸附钨(Ⅵ)性能的影响,测定了纳米零价铁对钨(Ⅵ)的吸附等温线和吸附动力学曲线。研究结果表明,制备的纳米零价铁具有典型的核-壳结构,其粒径在10~30nm之间,BET比表面积为53m^2/g。纳米零价铁对钨(Ⅵ)的回收率随着初始钨(Ⅵ)浓度和初始pH值的增大而减小。在25℃条件下,纳米零价铁对钨(Ⅵ)的平衡吸附容量为172.82mg/g。Langmuir等温线方程可以很好地拟合纳米零价铁对钨(Ⅵ)的吸附等温线,且纳米零价铁对钨(Ⅵ)吸附动力学曲线符合准二级动力学模型。Nano zero-valent iron（nZVI）was synthesized by the liquid-phase reduction method and characterized by powder X-ray diffraction（PXRD）,transmission electron microscope（TEM）,the Brunauer-Emmett-Teller（BET）and X-ray photoelectron spectroscopy（XPS）method.The adsorption performance of tungsten（HⅥ）on nZVI were investigated by adjusting the parameters,such as additive amount of nZVI,initial concentration of tungsten（Ⅵ）and initial pH value.In addition,the adsorption isotherms and kinetic curves of tungsten（Ⅵ）on nZVI were measured.Results showed that nZVI exhibited a regular core-shell structure with an average particle size of 10-30 nm and a BET surface area of 53 m^2/g.Furthermore,the adsorption capacity of tungsten（Ⅵ）decreased with the increasing of initial pH value and additive amount of nZVI.The maximum adsorption capacity of tungsten（Ⅵ）reached 172.82 mg/g at 25 ℃.The adsorption isotherms of tungsten（Ⅵ）on nZVI fitted well with Langmuir model,and the adsorption kinetics of tungsten（Ⅵ）on nZVI could be well described by apseudo-second-order kinetic model.

关 键 词：SCR催化剂 纳米零价铁 钨 吸附 热力学 动力学 

分 类 号：X773[环境科学与工程—环境工程]