偕胺肟乙烷基硅材料对铀(Ⅵ)的吸附机理研究  

Adsorption Mechanism of U(Ⅵ) by Amidoxime Ethane-bridged Periodic Mesoporous Silicas

作　　者：熊正为[1] 熊巍滔 王劲松[1] 陆森 朱雷[1] 陈婧[1] 

机构地区：[1]南华大学城市建设学院,湖南衡阳421001 [2]益阳市城市规划设计院,湖南益阳413000

出　　处：《环境科学与技术》2016年第10期47-51,共5页Environmental Science & Technology

基　　金：国家自然科学基金(21177053;11175081);南华大学科技创新团队项目(NHCXTD07)

摘　　要：以聚环氧乙烷-聚环氧丙烷-聚环氧乙烷三嵌段共聚物(P123)为模板剂,1,2-二(三乙氧基硅基)乙烷(BTSE)和正硅酸乙酯(TEOS)为混合硅源前驱物,(3-氰丙基)三乙氧基硅烷(NPTS)为硅烷偶联剂,经过胺肟化制备出了一种新型铀吸附剂-偕胺肟基乙烷桥键介孔二氧化硅(AO-PMOs)。分析吸附过程的等温吸附规律和反应动力学规律,并用傅里叶红外光谱仪(FT-IR)、扫描电镜(SEM)、能谱仪(EDS)分析吸附机理。结果表明:AO-PMOs对铀的吸附动力学较好地符合准二级动力学模型,表明该吸附过程以化学吸附为主;吸附等温线符合Langmuir模型,表明AO-PMOs对铀的吸附以单分子层吸附为主。傅里叶红外光谱图、扫描电镜图和能谱图表明:AO-PMOs表面有物质被吸附且证明该物质即为溶液中的铀;吸附铀后的偕胺肟基团发生变化,表明吸附铀主要是偕胺肟基团的作用。The amidoxime ethane-bridged periodic mesoporous silicas was synthesized by using poly（ethylene oxide）-poly（propylene oxide）-poly（ethylene oxide） triblock copolymer（P123） as template,1,2-bis（triethoxysilyl） ethane（BTSE） and tetraethoxysilane（TEOS） as framework precursors, 3-cyanopropyltriethoxysilane（NPTS）as silane coupling agent. The adsorption isotherms and reaction kinetic laws of the adsorption process were analyzed. Fourier transform infrared spectrometer（FT-IR）, scanning electron microscope（SEM） and energy dispersive spectrometer（EDS） were used for the analysis of the adsorption mechanism. Results showed that the adsorption kinetic of U（ Ⅵ） by AO-PMOs conformed to pseudo-second order kinetic model, which proved that adsorption process was given priority to chemical adsorption;adsorption isotherm in line with the Langmuir model revealed that the adsorption of U（ Ⅵ） by AO-PMOs was mainly monolayer adsorption. The diagrams of FT-IR, SEM and EDS showed that the material adsorbed in the surface of AO-PMOs was U（ Ⅵ）, and the amidoxime group＇s changes after adsorption indicated that the adsorption of U（ Ⅵ） were primarily depended on them.

关 键 词：偕胺肟基 乙烷桥键 二氧化硅 吸附机理 

分 类 号：X703.1[环境科学与工程—环境工程]