摘要
以环氧氯丙烷为交联剂,将聚酰胺胺树状大分子(PAMAM)接枝到稻草基体上,利用FTIR、SEM、XRD、TG等对其结构进行了表征和分析。考察了其对Nd^3+、Sm^3+、La^3+稀土金属离子的吸附性能,探讨了吸附时间、稀土金属离子浓度、吸附温度、溶液pH等因素对吸附性能的影响。同时对吸附过程的动力学、吸附等温线和吸附热力学进行了研究。结果表明,所制备的吸附剂对Nd^3+、Sm^3+、La^3+稀土金属离子的吸附平衡时间约为4 h,平衡吸附量分别为47.14、40.11和50.12 mg/g。吸附过程符合拟二级动力学模型和Freundlich等温线,表明此吸附过程是属于化学吸附过程。吸附热力学研究表明,此吸附过程是自发进行的,同时吸附过程是一个混乱度增加的熵增过程。
A novel absorbent,polyamidoamine(PAMAM)dendrimer grafted rice straw was prepared using epichlorohydrin as crosslinking agent.Its structure was characterized and analyzed by FTIR,SEM,XRD and TG.The adsorption properties of the functionalized rice straw for Nd^3+,Sm^3+and La^3+from aqueous solution were researched.The effects of adsorption time,initial rare earth metal ions concentration,adsorption temperature,pH and other factors on the adsorption properties of these rare earth metal ions were investigated.At the same time,the kinetics behavior,adsorption isotherm,and thermodynamics parameters of the adsorption process were studied.The adsorption mechanism of this adsorption process was discussed.The results showed that the adsorption equilibrium time of the prepared absorbent for Nd^3+,Sm^3+and La^3+was all about 4 h.And the corresponding adsorption capacities were 47.14,40.11 and 50.12 mg/g,respectively.The adsorption process conformed to the pseudo-second-order kinetics model and the Freundlich isotherm model was more appropriate for tracing the adsorption behavior,indicating that the adsorption process was a chemical adsorption process.In additional,the thermodynamics studies showed that the adsorption was a spontaneous and entropy increasing process.
作者
章昌华
郭明
涂伟萍
许立信
ZHANG Changhua;GUO Ming;TU Weiping;XU Lixin(School of Chemistry and Chemical Engineering,Anhui University of Technology,Maanshan 243002,Anhui,China;School of Chemistry and Chemical Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China;Anhui University of Technology Chemical Science&Technology Co.,Ltd.,Maanshan 238251,Anhui,China)
出处
《精细化工》
EI
CAS
CSCD
北大核心
2020年第3期584-589,597,共7页
Fine Chemicals
基金
安徽省教育厅重点项目(KJ2017A047)。
