季铵盐改性蒙脱土的微观结构与表面分形特征  

The Microstructure and Surface Fractal Characters of Montmorillonite Modified by Quaternary Ammonium Salts

作　　者：郑广 高芒来 罗忠新 李晓燕 

机构地区：[1]中国石油大学(北京)理学院重质油国家重点实验室,北京102249

出　　处：《石油化工高等学校学报》2011年第1期6-11,共6页Journal of Petrochemical Universities

基　　金：北京市教委共建计划项目(XK114140479)

摘　　要：以两种双子季铵盐(MD,DMB)和一种单季铵盐(HTMAB)为有机改性剂,通过阳离子交换法对Na蒙脱土改性,制得季铵盐有机改性蒙脱土。采用N2吸附法、X射线衍射(XRD)及红外光谱分析(FT-IR)研究了季铵盐有机改性蒙脱土的微观结构及表面特征。结果表明,经MD,DMB及HTMAB改性后,蒙脱土BET比表面积及层间距均有所减小,这与传统长链单季铵盐的改性效果不同;有机改性后,季铵盐阳离子成功吸附于蒙脱土的层间,蒙脱土的微观结构发生了改变,形成微孔和介孔同时存在的二维交错多孔结构,表面由亲水性转变为疏水性,且改性蒙脱土分形维数D较原土有所减小,表明改性土孔隙分布更加均匀。Na-montmorillonite（Na-MMT） was modified by gemini quaternary ammonium salts（MD,DMB） and mono-quaternary ammonium salt（HTMAB） through the intercalation.Changes in the surfaces and microstructure were characterized using N2 adsorption isotherms,X-ray diffraction（XRD）,and fourier transform infared spectrometer（FT-IR）.The results show that the BET surface area and the basal spacings of MMT are reduced when modified by MD,DMB or HTMAB,which is contrast to the MMT when modified by the monovalent quaternary ammonium salts with long chain.The quaternary ammonium salts have intercalate into the interlamellar space of montmorillonite and the microstructure has changed.The surface properties change from hydrophilic to hydrophobic.In addition,the fractal dimension（D） of organo-MMT is decreased,that is to say,the porosity distribution is more uniformity.

关 键 词：蒙脱土 季铵盐 有机改性 微观结构 表面分形特征 

分 类 号：O647.3[理学—物理化学]