改性微晶纤维素水凝胶对水中U(Ⅵ)的吸附性能研究  

Study on the adsorption performance of modified microcrystalline cellulose hydrogels on U(Ⅵ)in water

作　　者：林毅 谢水波 张澜涛[1] 史艳丹 刘迎九 李绪忠 LIN Yi;XIE Shui-bo;ZHANG Lan-tao;SHI Yan-dan;LIU Ying-jiu;LI Xu-zhong(College of Civil Engineering,University of South China,Hengyang 421001,China;Key Laboratory of Pollution Control and Resource Utilization Technology in Hunan Province,University of South China,Hengyang 421001,China;Changsha Nonferrous Metallurgy Design and Research Institute,Changsha 410000,China)

机构地区：[1]南华大学土木工程学院,湖南衡阳421001 [2]南华大学污染控制与资源化技术湖南省高校重点实验室,湖南衡阳421001 [3]长沙有色冶金设计研究院,湖南长沙410000

出　　处：《应用化工》2023年第12期3303-3308,共6页Applied Chemical Industry

基　　金：湖南省自然科学基金(2021JJ30579)。

摘　　要：采用化学沉积法制备了微晶纤维素负载二氧化锰水凝胶(MCC@MnO_(2)/SA),用于吸附水中U(Ⅵ)。通过SEM-EDS、FTIR、XPS对水凝胶进行表征,并考察了不同pH值、接触时间、温度、U(Ⅵ)初始浓度条件下MCC@MnO_(2)/SA对U(Ⅵ)的吸附影响。结果表明,在U(Ⅵ)初始浓度为10 mg/L、pH值为4、温度为303 K,吸附6 h时,MCC@MnO_(2)/SA对U(Ⅵ)的最大吸附量达234.11 mg/g,比改性前提高了11%左右。吸附过程符合拟二级动力学,其等温吸附模型更契合Langmuir,主要为单分子层化学吸附,吸附是自发吸热过程;主要吸附机理是化学吸附和共价金属离子与表面电子结合产生的价力,MnO_(2)提供了更多官能团。该水凝胶经5次循环后去除率仍保持78%以上,具有再生利用性。Microcrystalline cellulose-supported manganese dioxide hydrogels(MCC@MnO_(2)/SA)were prepared by chemical deposition and used to adsorb U(Ⅵ)in water.The hydrogels were characterized by SEM-EDS,FTIR and XPS,and the adsorption effect of MCC@MnO_(2)/SA on U(Ⅵ)under different factors(pH,contact time,temperature,initial concentration of U(Ⅵ))was investigated.The results showed that when the initial concentration of U(Ⅵ)was 10 mg/L,the pH value was 4 and the temperature was 303 K,the maximum adsorption capacity of U(Ⅵ)by MCC@MnO_(2)/SA reached 234.11 mg/g,which was about 11%higher than that before modification.The adsorption process conforms to the quasi-secondary kinetics,and its isothermal adsorption model is more suitable for Langmuir,mainly monolayer chemical adsorption,its adsorption is a spontaneous endothermic process.The main adsorption mechanism is chemical adsorption and valence forces generated by the combination of covalent metal ions and surface electrons,and MnO_(2)provides more functional groups.The removal rate of the hydrogel remained above 78%after 5 cycles,which was recyclable.

关 键 词：U(Ⅵ) 水凝胶 微晶纤维素 二氧化锰 

分 类 号：TQ316.6[化学工程—高聚物工业] X703[环境科学与工程—环境工程]