Cr(Ⅵ)在改性蒙脱土上吸附行为的研究  

The adsorption behavior of Cr(Ⅵ) on modified montmorillonite

作　　者：关文斌[1] 赵彬侠[1] 邱爽[1] 刘楠[1] 牛露[1] 陈蓉[1] 孙烨[1] 

机构地区：[1]西北大学化工学院,陕西西安710069

出　　处：《西北大学学报（自然科学版）》2016年第3期375-380,共6页Journal of Northwest University（Natural Science Edition）

基　　金：陕西省科技厅社发攻关基金资助项目(2013K13-01-04)

摘　　要：采用溶胶-凝胶法制备了Ti-MMT和Ti-Si-MMT吸附剂,利用XRD,N2吸附-脱附和FTIR对样品进行表征,并考察了其对Cr(Ⅵ)的吸附,研究了改性蒙脱土吸附Cr(Ⅵ)的吸附动力学和吸附等温线。经改性后,钛硅成功进入蒙脱土层间使层间距由原来的1.53nm分别增大到1.78nm和1.86nm,比表面积由42.09m^2/g分别增大到110.53m^2/g和304.72m^2/g;相同条件下,对Cr(Ⅵ)去除率高低顺序依次是Ti-Si-MMT,Ti-MMT,MMT,其中Ti-Si-MMT去除效果最高可达98%以上,远高于Ti-MMT和MMT;Ti-Si-MMT和TiMMT吸附Cr(Ⅵ)过程均符合拟二级动力学模型和Langmuir等温方程,吸附机理主要是静电吸附和化学吸附。Ti-Si-MMT是一种处理含Cr(Ⅵ)废水有潜力的吸附剂。Ti-MMT and Ti-Si-MMT were prepared by sol-gel method. The adsorbents were characterized by XRD,N2adsorption-desorption and FTIR. The samples were used for Cr（ Ⅵ） adsorption and the adsorption kinetics and isotherms were also studied. It was shown that titanium and silicon were introduced into montmorillonite by modification,leading to the spacing of materials increased from 1. 53 nm to 1. 78 nm and 1. 86 nm,specific surface area increased from 42. 09 m^2/ g to 110. 53 m^2/ g and 304. 72 m^2/ g,respectively; the order of removal for Cr（ Ⅵ） is Ti-Si-MMT,Ti-MMT,MMT under the same condition and Ti-Si-MMT could reach more than 98%,much higher than Ti-MMT and MMT. The adsorption process follows pseudo-two-order kinetics and Langmuir isothermal equation. The sorption mechanisms are mainly electrostatic adhesion and chemical adsorption. Ti-Si-MMT is suitable to be used as a potential adsorbent to remove Cr（ Ⅵ）.

关 键 词：改性蒙脱土 Cr(Ⅵ) 吸附 机理 

分 类 号：O647.31[理学—物理化学]