壳聚糖-生物炭复合材料对U(Ⅵ)的吸附性能试验研究  

Experimental Investigation on Adsorption of U(Ⅵ) by Chitosan-biochar Composite

作　　者：高翔 谢水波[2] 刘迎久 曾涛涛[1,2] 莫官海 GAO Xiang;XIE Shuibo;LIU Yingjiu;ZENG Taotao;MO Guanhai(School of Civil Engineering,University of South China,Hengyang 421001,China;Hunan Provincial Key Laboratory of Pollution Control and Resources Technology,University of South China,Hengyang 421001,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重点实验室,湖南衡阳421001

出　　处：《原子能科学技术》2019年第8期1350-1358,共9页Atomic Energy Science and Technology

基　　金：国家自然科学基金资助项目(11475080,51408293);南华大学研究生科学基金资助项目(2018KYY097)

摘　　要：以壳聚糖(CTS)和生物炭(AC)为原料,采用原位沉淀法制备了壳聚糖-生物炭(CTS-AC)复合材料,研究了吸附时间、铀初始浓度、初始pH值、温度和干扰离子等因素对CTS-AC吸附U(Ⅵ)的影响,探讨了CTS-AC对U(Ⅵ)的吸附动力学、等温线,采用傅里叶红外光谱(FT-IR)、X射线衍射(XRD)、扫描电镜(SEM-EDS)及比表面积分析(BET)等手段进行了相关机理分析。实验结果表明,CTS-AC吸附U(Ⅵ)的最佳条件为:pH=4、CTS-AC投加量0.8~1 g/L、吸附时间240 min,在此条件下,最大吸附率可达94.85%。CTS-AC对U(Ⅵ)的吸附等温线模型符合Langmuir模型,U(Ⅵ)的吸附动力学符合准二级模型;高浓度Cu^2+对CTS-AC吸附U(Ⅵ)的抑制作用明显;FT-IR、XRD和EDS结果表明,CTS的负载未改变AC的原结构,仅增大了其孔径、增加了结合位点。CTS-AC对U(Ⅵ)的吸附机制为配位作用以及离子交换。Chitosan-biochar(CTS-AC)composites were prepared by using chitosan(CTS)and biochar(AC)as raw materials.The effect of initial U(Ⅵ)concentration,reaction time,initial pH,reaction temperature and interference ion on the adsorption of U(Ⅵ)by CTS-AC was investigated,and the adsorption behavior of U(Ⅵ)by CTS-AC was characterized by FT-IR,XRD,SEM-EDS and specific surface area analysis(BET).The results show that the optimum conditions for the adsorption of U(Ⅵ)by CTS-AC are pH=4,dosage of CTS-AC 0.8-1 g/L and adsorption time 240 min.Under these conditions,the maximum adsorption rate can reach 94.85%.The isothermal thermodynamic data of the adsorption of U(Ⅵ)by CTS-AC accord with the Langmuir model,and the adsorption kinetics is in accordance with the quasi-second-order kinetic model.The inhibiting effect of high concentration of Cu^2+on the adsorption of U(Ⅵ)by CTS-AC is obvious.The results of FT-IR,XRD and EDS show that adding CTS dose not change the original structure of AC,but the pore size and the binding sites increase.The adsorption mechanisms are coordination and ion exchange.

关 键 词：壳聚糖-生物炭 U(Ⅵ) 吸附机理 

分 类 号：O647.3[理学—物理化学]