席夫碱改性MCM-41分子筛的制备及其对铅离子的吸附性能  

Characterization of Schiff Base Modified MCM-41 Molecular Sieve for Adsorption of Lead Ions from Aqueous Solution

作　　者：吴红梅[1] 徐靖雯 郭宇[1] 张震斌[1] WU Hong-Mei;XU Jing-Wen;GUO Yu;ZHANG Zhen-Bin(School of Chemical and Environmental Engineering,Liaoning University of Technology,Jinzhou 121001,China)

机构地区：[1]辽宁工业大学化学与环境工程学院,锦州121001

出　　处：《分析化学》2024年第1期102-112,共11页Chinese Journal of Analytical Chemistry

基　　金：辽宁省“兴辽英才计划”项目(No.XLYC2007171);辽宁省自然科学基金项目(No.2021-MS-321)资助。

摘　　要：以2-吡啶甲醛为席夫碱配体,采用后接枝法将其接枝到MCM-41分子筛上,获得了一种新型席夫碱改性MCM-41分子筛(N-MCM-41),实现了对水溶液中铅离子(Pb^(2+))的有效吸附。利用X-射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、红外光谱(FT-IR)、热重分析(TGA)和X-射线光电子能谱(XPS)等对N-MCM-41的结构、形貌、表面官能团和化学状态进行了分析,并系统研究了N-MCM-41对水溶液中Pb^(2+)的吸附行为。此吸附剂对Pb^(2+)的最大吸附容量达到101.3 mg/g。N-MCM-41对Pb^(2+)的吸附行为符合准二级动力学模型和Langmuir等温线模型,并且吸附过程是自发和吸热的过程。N-MCM-41表面官能团与Pb^(2+)的螯合配位作用是去除水体中Pb^(2+)的主要机制。N-MCM-41吸附剂经过5次再生后,仍然保持良好的吸附性能,在处理水体铅污染中具有良好的应用前景。A new Schiff base modified MCM-41 molecular sieve(N-MCM-41)was synthesized via post-grafting method with 2-pyridine formaldehyde for efficient removal of lead ions(Pb^(2+))from aqueous solution.X-ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM),Fourier transform-infrared(FT-IR)spectroscopy,thermogravimetric analysis(TGA),and X-ray photoelectron spectroscopy(XPS)were employed to characterize the structure,morphology,surface functional groups and chemical states of N-MCM-41.Moreover,the adsorption behavior of Pb^(2+)by N-MCM-41 was systematically studied.Batch adsorption studies revealed that N-MCM-41 showed the maximal adsorption capacity of 101.3 mg/g at 45℃and pH=5.5 under the initial Pb^(2+)concentration of 80 mg/L after 180 min adsorption.The adsorption process conformed to the Langmuir isotherm model and the pseudo-second-order kinetics model.The adsorption of Pb^(2+)by N-MCM-41 was a spontaneous and endothermic process.Adsorption mechanism analyses suggested that functional groups on N-MCM-41 had strong coordination ability with Pb^(2+)to improve the adsorption capacity.The synthesized N-MCM-41 adsorbent exhibited excellent reusability in five regeneration cycles.Overall,this study showed that the N-MCM-41 had good application prospect to remove Pb^(2+)from aqueous solution.

关 键 词：MCM-41分子筛 席夫碱 改性 吸附 铅离子 

分 类 号：TQ424.25[化学工程] X703[环境科学与工程—环境工程]