ZIF-8-SiO_(2)的制备及其对U(Ⅵ)的吸附  

ZIF-8-SiO_(2) and adsorption on U(Ⅵ)

作　　者：樊元睿 张炜[1] 陈元涛[1] 覃建娴 FAN Yuanrui;ZHANG Wei;CHEN Yuantao;QIN Jianxian(College of Chemistry and Chemical Engineering,Qinghai Normal University,Xining 810008,China)

机构地区：[1]青海师范大学化学与化工学院,西宁810008

出　　处：《复合材料学报》2021年第9期3056-3064,共9页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金(21667024)。

摘　　要：以沸石咪唑酯骨架结构材料ZIF-8及硅酸四乙酯(TEOS)为原料制备ZIF-8-SiO_(2)复合材料,并采用XRD、SEM、EDS等方法对ZIF-8-SiO_(2)的结构及吸附U(Ⅵ)前后的形貌进行表征,结果表明ZIF-8-SiO_(2)成功制备且对U(Ⅵ)具有良好的吸附作用。以静态吸附实验,分别考察了pH值、时间、温度、溶液初始铀浓度、盐浓度及超高压环境等对ZIF-8-SiO_(2)吸附性能的影响。由实验结果可得,在初始浓度为80 mg·L^(-1)时,25℃下ZIF-8-SiO_(2)对U(Ⅵ)的最大实际吸附量为498 mg·g^(-1),根据Langmuir模型拟合结果分析得出,ZIF-8-SiO_(2)对U(Ⅵ)的理论吸附量最高可达678.5 mg·g^(-1),且在200~500 MPa范围内,压强越高越有利于吸附。通过FTIR、XPS等方法对ZIF-8-SiO_(2)吸附铀酰离子前后的结构进行分析,探究该吸附过程中可能存在的吸附机制。Zeolite imidazole ester framework structure material ZIF-8 and TEOS were used to prepare ZIF-8-SiO_(2)composite,the structure of ZIF-8-SiO_(2)and the morphology before and after adsorption of U(Ⅵ)were characterized by XRD,SEM,EDS.And the results show that ZIF-8-SiO_(2)is successfully prepared and has a good adsorption effect on U(Ⅵ).The effects of pH value,time,temperature,initial uranium concentration and salt concentration on the adsorption performance of ZIF-8-SiO_(2)were investigated by static adsorption experiments.According to the experimental results,when the initial concentration is 80 mg·g^(-1),the maximum actual adsorption capacity of ZIF-8-SiO_(2)on U(Ⅵ)at 25℃is 498 mg·g^(-1),and according to the analysis of Langmuir model fitting results,the theoretical adsorption capacity of the material on U(Ⅵ)is up to 678.5 mg·g^(-1).And in the range of 200~500 MPa,the higher the pressure,the better the adsorption.FTIR and XPS were used to characterize the structure of the material before and after uranylion adsorption,to explore the possible adsorption mechanism during the adsorption process.

关 键 词：ZIF-8-SiO_(2) 复合材料 铀处理 吸附法 高压模拟 

分 类 号：O643.19[理学—物理化学]