β-环糊精聚合物微球对Zn2的吸附行为及机理-食品科学.PDFVIP

※基础研究 食品科学 2011, Vol. 32, No. 01 35 Zn2+ 李仲谨，杨 威，刘 艳，赵 燕，李健基 ( 陕西科技大学化学与化工学院，教育部轻化工助剂化学与技术重点实验室，陕西 西安 710021) 　　 以β- 环糊精为原料，环氧氯丙烷为交联剂，采用反相乳液聚合得到一种交联 β- 环糊精聚合物( β-CDP)微 球，研究其对 Zn 2+ 的静态吸附行为，测定吸附等温线，分析吸附热力学性质和动力学特征，并用红外光谱仪、 X 射线衍射仪和综合热重仪对 β-CDP 微球吸附 Zn2+ 前后对照分析，探讨吸附机理。结果表明：在实验条件范围 内，β-CDP 微球对 Zn2+ 吸附等温线同时符合Langmuir 等温方程和 Freundlich 等温方程；在不同温度下， β-CDP 微 球吸附 Zn2+ 的吸附焓变( ΔH) 、熵变( ΔS) 、吉布斯自由能( ΔG)均为负值，吸附是自发的放热过程； β-CDP 微球主 要通过物理吸附和配位吸附等方式吸附Zn2+ ，这些吸附作用增强了交联链的热稳定性、破坏了β-CDP 微球的结晶结构。 β- 环糊精聚合物微球；Zn 2+ ；吸附机理；动力学 Adsorption Behavior and Mechanism of Zinc (II) on β-Cyclodextrin Polymer Microspheres LI Zhong-jin ，YANG Wei ，LIU Yan ，ZHAO Yan ，LI Jian-ji (Key Laboratory of Auxiliary Chemistry and Technology for Chemical Industry, Ministry of Education, College of Chemistry and Chemical Engineering, Shaanxi University of Science and Technology, Xi ’an 710021, China) Abstract ：The static adsorption behavior of Zn2+ on β-cyclodextrin polymer ( β-CDP) microspheres prepared by crosslinking of β-cyclodextrin with epichlorohydrin and subsequent reversed-phase emulsion polymerization was investigated, and the isothermal adsorption curves and the adsorption thermodynamics and kinetics characteristics were measured at different temperatures. Meanwhile, structural changes in β-CDP microspheres before and after Zn2+ adsorption were examined through FT-IR spectroscopic and X-ray diffraction (XRD) observations and thermogravimetric analysis (TGA), and the adsorption mechanism was also discussed. The results showed that the adsorption of Zn2+ on β-CDP microspheres complied with both Langmuir and Freundlich isotherm adsorption equations. The enthalpy change ( Δ