原位制备磁性壳聚糖纳米粒子及其对Ag(I)的吸附性能论文.doc

毕业设计(论文)
题目: 原位制备磁性壳聚糖纳米粒子及其对Ag(I)的吸附性能
Title: In-situ preparation of ic chitosan Nanoparticles and their adsorption properties for Ag (I) ions
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二零一二年六月
摘要
以壳聚糖、Fe2+/ Fe3+盐为水相,环已烷/正已醇为油相,Triton X-100为乳化剂,通过在W/O微乳体系中加NaOH溶液沉淀剂,原位制备磁性壳聚糖纳米粒子(MCN),用于吸附Ag(I)。考察了pH值、Ag (I)吸附Ag (I)的影响。结果表明,MCN分散良好,粒径15–40 nm, emu·g-1。pH= , Ag (I)吸附容量随温度升高。吸附动力学符合拟二级方程,且为自发放热过程。吸附等温线分别用Langmuir,Freundich和D-R模型拟合,表明Langmuir模型拟合最好,为单分子层吸附,。吸附活化能E=~ kJ/mol,表明以化学吸附为主。
关键词:原粒制备; 磁性壳聚糖; 吸附; Ag (I)
ABSTRACT
The ic chitosan nanoparticles (MCN) were in-situ prepared by adding the NaOH solution precipitant into a W/O microemulsion system, which posed of chitosan and Fe2+/ Fe3+ salts solution as water phase, cyclehexane/n-hexanol as oil phase, and Triton X-100 as emulsifier. The influences of different parameters such as pH, initial Ag (I) concentration, and temperature on Ag (I) adsorption by MCN were investigated. The results showed that MCN were monodispersed, and had a particle size of 15–40 nm and a saturation ization of . The optimum pH value for Ag(I) adsorption was pH . The Ag(I) adsorption capacity decreased with increasing the temperature. The adsorption ic was fitted well with the second-order model and the adsroption process was spontaneous and exothermic. Langmuir, Freundlich and D–R models were used for fitting the equilibrium data, and the results showed very good fits with the Langmuir isotherm equation for the monolayer adsorption process, and the maximum adsorption capacity was mmol/g. The E values (E=~ kJ/mol) indicated that the adsorption was predominant on the chemisorption.
Keywords: In-situ preparation; ic chitosan; Adsorption; Ag(I) ions
目录
1. 绪论 1
壳聚糖 1
壳聚糖的应用 2
磁性微球 3
磁性微球的制备 3
包埋法 3
化学共沉淀法 4
交联聚合法 4
磁性微球在含金属废水的污水处理中的应用 4
本文的研究目的 5
2. 实验部分 6
实验仪器及主要试剂 6
实验方案 6
样品表征 7
2. 4 吸附/脱附 7
3. 结果与讨论 8
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