环境工程毕业论文.doc

本科毕业论文题目: 壳聚糖两种形态吸附重金属及其吸附后的比较研究学院:化学工程学院专业:环境工程班级: 1002051 学号: 100205116 学生姓名:荣亚运指导教师: 陈荣平职称:讲师二零一四年六月三日壳聚糖两种形态吸附重金属及其吸附后的比较研究摘要壳聚糖是一种天然高分子, 分子中含有大量的氨基和羟基, 对金属离子有很好的吸附能力。通过交联改性的方法可以提高壳聚糖的物理、化学性质。在本文中,主要研究了壳聚糖两种形态即壳聚糖微球和壳聚糖大球对重金属 Pb(Ⅱ)和Cu(Ⅱ) 的吸附性能,其中包含了该两种重金属一元体系的研究和混合体系的研究并在最后进行了壳聚糖两种形态吸附性能的比较。在研究吸附的过程中,分别研究了 pH,温度,动力学对吸附的影响。吸附热力学研究的结果比较符合 Langmuir 模型,吸附动力学的研究结果可以很好的用二级模型来描述。通过对重金属 Pb(Ⅱ)和Cu(Ⅱ) 混合体系的吸附研究发现壳聚糖在不同的 pH条件下,表现出不同的吸附选择性。壳聚糖两种形态的比较结果是壳聚糖微球的吸附性能要比壳聚糖大球好很多。而且为了更好的研究吸附机理,本实验还做了红外谱图和 XPS 。通过 XPS 的研究可以很清楚的看到壳聚糖在吸附重金属前后,峰的强度发生的变化,并证明壳聚糖确实吸附了该重金属。关键字:壳聚糖;重金属;吸附机理 parative study of two forms of chitosan and its adsorption of heavy metal adsorption abstract Chitosan isone of the most abundant natural polymers, this biopolymer has useful functional groups such as hydroxyl and amine, so it can interact with metal ions. It is available to enhance physical and chemical property by cross-linked modification of chitosan. In this paper , the effects of the two forms of chitosan that chitosan microspheres and big ball which a dsorption of heavy metal Pb(Ⅱ) and Cu (Ⅱ), which includes the study of the unitary system of two heavy metals hybrid systems and research and pared the two forms of chitosan adsorption properties. In the course of the adsorption were studied pH, temperature, influence on the adsorption ics. Comparison of the results of the adsorption thermodynamics of the Langmuir model and adsorption ics study results can be well described by two models. Through the study of the adsorption of heavy metals Pb(Ⅱ) and Cu (Ⅱ) found that chitosan hybrid system under different pH conditions, showing different adsorption selectivity. Comparison of the two forms is the result of chitosan adsorption properties of chitosan chitosan microspheres much better than the big ball. And in order to better study the adsorption mechanism, the experiment also made infrared spectra and XPS. You can clearly see the change before and after the adsorption of heavy metal chitosan, the intensi