摘要
利用桉树叶提取液制备铁镍纳米颗粒(Fe/Ni NPs),并将其用于去除水中六价铬(Cr(Ⅵ)).扫描电子显微镜-能量色散X射线光谱(SEMEDS)分析表明Fe/Ni NPs与Cr(Ⅵ)之间发生了相互作用,但反应前后Ni的含量几乎没有变化. X射线光电子能谱(XPS)则表明反应后材料表面存在三价铬(Cr(Ⅲ)).循环伏安曲线证明Fe NPs与Cr(Ⅵ)反应有还原峰出现,Ni的掺杂加速了吸附剂与吸附质间的电子转移.吸附动力学模型拟合结果表明,Fe/Ni NPs吸附Cr(Ⅵ)的过程符合准二级动力学模型,说明吸附过程主要是化学控制的.Weber-Morris粒子内扩散模型拟合结果表明,反应速度由液膜扩散和内扩散共同控制.还原动力学很好地符合准一级动力学过程.反应活化能E为41.137 kJ·mol^(-1),表明Fe/Ni NPs对Cr(Ⅵ)的吸附和催化还原过程主要由化学反应控制.
Fe/Ni nanoparticles(Fe/Ni NPs)were prepared by eucalyptus leaf extract and used to remove Cr(Ⅵ)from aqueous solution. Scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDS)showed that Fe/Ni NPs interacted with Cr(Ⅵ)and the content of Ni was basically unchanged. X-ray photoelectron spectroscopy(XPS)indicated that Cr(Ⅵ)was adsorbed onto Fe/Ni NPs and reduced to Cr(Ⅲ). Cyclic voltammetry curve(C-V curve)proved that both Fe NPs and Cr(Ⅵ)had reduction peaks,and Ni doping accelerated electron transfer. The kinetic data was well fitted by the pseudo-second-order model,suggesting that chemisorption dominated the Cr(Ⅵ)removal process. Moreover,Weber-Morris model revealed that adsorption process was controlled by both the liquid film diffusion and intraparticle diffusion. The reduction kinetics data fitted well to a pseudo-first-order model. The activation energy(Ea)of 41.137 kJ·mol^(-1)confirmed that the adsorption and catalytic reduction of Cr(Ⅵ)by Fe/Ni NPs were mainly controlled by chemical reactions.
作者
金晓英
杨露
林强
李恒
陈祖亮
JIN Xiaoying;YANG Lu;LIN Qiang;LI Heng;CHEN Zuliang(College of Environmental Science and Engineering,Fujian Normal University,Fuzhou 350007;Key Laboratory of Pollution Control and Resource Reuse of Fujian Province,Fuzhou 350007;Fujian Soil and Water Conservation Test Station,Fuzhou 350001)
出处
《环境科学学报》
CAS
CSCD
北大核心
2022年第10期284-292,共9页
Acta Scientiae Circumstantiae
基金
国家自然科学基金(No.52174158)
福建省水利科技项目(No.MSK202208)。
