氨基化改性壳聚糖磁性树脂的原位制备及其对UO_2^(2+)的吸附性能  

In-Situ Preparation of Amine Functionalized Chitosan Magnetic Resins for Uranyl(Ⅱ) Adsorption

作　　者：黄志伟[1] 周利民[1] 黄国林[1] 邹洪斌[1] 王云[1] 

机构地区：[1]省部共建核资源与环境国家重点实验室培育基地(东华理工大学),江西南昌330013

出　　处：《高校化学工程学报》2016年第3期716-722,共7页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(21166001;21366001;11375043);江西省自然科学基金(20132BAB203019)

摘　　要：利用NaOH/Fe^(2+)反应体系生成Fe(OH)_2,同时通入低浓度O_2使Fe(OH)_2氧化成Fe_3O_4,在壳聚糖基质内部均匀生成磁性物质;并利用三聚磷酸钠交联,原位制备氨基化改性磁性壳聚糖树脂(TETA-MCR)。考察了不同pH、吸附时间、初始浓度及温度对TETA-MCR吸附UO_2^(2+)性能的影响。FT-IR分析表明氨基是UO_2^(2+)主要吸附位,通过配位络合吸附UO_2^(2+)。吸附动力学符合拟二级动力学模型,并且为自发吸热过程。吸附等温线符合Langmuir模型,298 K时最大吸附容量达166.6 mg UO_2^(2+)×g^(-1)。TETA-MCR对UO_2^(2+)吸附具有吸附容量较高、易于磁分离、可重复使用的优点,可作为UO_2^(2+)分离的新型磁性吸附剂。Amine functionalized chitosan magnetic resins（TETA-MCR） were prepared in-situ via sodium tri-polyphosphate（TPP） crosslinking. Fe3O4 was uniformly produced within the resins from Fe（OH）2（synthesized with NaOH and Fe^2＋） oxidization by low concentration O2. The effects of different parameters such as pH, contact time, initial UO2^2＋ concentration and temperature on UO2^2＋ adsorption by TETA-MCR were investigated. FT-IR results indicate that amine groups are the main active sites for UO2^2＋ adsorption through chelation. The adsorption process is spontaneous and endothermic in nature, and it kinetically follows the pseudo-second-order model. The equilibrium isotherms can be well fitted by the Langmuir model with a maximum adsorption capacity of 166.6 mg UO2^2＋×g^-1 at 298 K. TETA- MCR can be used as a novel magnetic sorbent for UO2^2＋ separation as it has unique properties such as high adsorption capacity, easy magnetic separation and excellent reusability.

关 键 词：壳聚糖 磁性树脂 氨基化改性 UO22+吸附 

分 类 号：TQ424[化学工程]