【作者】 叶盛权；

【导师】 郭祀远；

【作者基本信息】 华南理工大学 ， 制糖工程， 2010， 博士

【摘要】 壳聚糖（Chitosan）是天然产物甲壳素（Chitin）的脱乙酰基产物,化学名称为1,4-2-氨基-2-脱氧-β-D-葡萄糖。壳聚糖以其独特的生物相容性、无毒、生物活性和物化特性引起人们的重视,在水处理、化工、轻纺、食品和医药等领域有广泛的应用前景。但由于其分子呈紧密的晶态结构,限制了它的应用活性和应用领域。对壳聚糖进行改性是改善其应用性能的有效途径。本研究将磁场和超声波处理等物理场强化技术应用于壳聚糖改性,以加快其反应速度和提高其反应产率,并改善壳聚糖及其衍生物的应用性能,为开发壳聚糖衍生物新型高效水处理剂提供基础研究数据。主要研究内容和结果如下:一、磁场强化壳聚糖与亚铁离子配合反应的研究研究磁场强化壳聚糖亚铁离子配合物的合成,主要研究磁场强化壳聚糖与硫酸亚铁铵反应,合成壳聚糖亚铁离子配合物的反应条件。包括磁场强度、磁场处理时间、反应物配比、反应温度、反应体系的pH值、亚铁离子的起始浓度、壳聚糖的用量等。结果表明,采用适当强度的恒磁场（100mT～150mT）能促进壳聚糖亚铁离子配合物的合成,在最佳条件下,反应的瞬时速率可提高23%,产物的离子配合量可提高24%。比较恒磁场处理前后的壳聚糖特性的结果显示,恒磁场不会改变溶液中壳聚糖的粘均分子量和脱乙酰度,产物的分子结构也不会改变。二、超声场强化壳聚糖醚化反应的研究将超声波技术引入壳聚糖与环氧丙烷的反应中,研究超声功率、超声处理时间、反应物配比、反应温度、反应体系的pH等对羟丙基壳聚糖的合成反应的影响。结果表明,采用超声波技术能加快羟丙基壳聚糖的合成,可减少环氧丙烷和催化剂的用量。其优化条件为:环氧丙烷、催化剂与壳聚糖的用量比为10ml∶0.8 ml∶1 g,反应温度控制在60℃～70℃,超声处理时间为3 h,超声功率为120W。在此超声强化反应条件下,产品得率和取代度分别提高13.6%和12.9 %。并通过碘仿反应、傅立叶红外光谱和X射线衍射对产物的结构进行了鉴定。三、磁场强化羟丙基壳聚糖亚铁离子配合物吸附性能的研究在制备出羟丙基壳聚糖亚铁离子配合物的基础上,引入磁场辅助处理技术,研究恒定磁场作用下羟丙基壳聚糖亚铁离子配合物对Pb（II）、Cu （II）、Cr（VI）三种过渡金属离子的吸附性能。实验结果表明,羟丙基壳聚糖亚铁离子配合物的吸附效果受到磁场强度、溶液pH、金属离子及溶液初始浓度等条件的影响。当磁场感应强度在200 mT～1000 mT范围内,羟丙基壳聚糖亚铁离子配合物对Pb（II）、Cu （II）、Cr（VI）三种过渡金属离子的吸附率和吸附量都随磁场强度增加而增加,并在pH4～pH5间有一个吸附最适值,离子溶液浓度分别应控制在30mg/L～40 mg/L。四、羟丙基壳聚糖亚铁离子配合物吸附动力学研究研究磁场作用下壳聚糖及其衍生物对Cr（VI）、Cu （II）、Pb（II）等三种金属离子的吸附动力学。结果表明,壳聚糖及其衍生物的吸附性能依次为:羟丙基壳聚糖亚铁离子>羟丙基壳聚糖>壳聚糖;它们对三种过渡金属离子的吸附性能次序均为Cu （II）> Pb（II） >Cr（VI）。用经典等温方程对壳聚糖及其衍生物对Cr（VI）、Cu （II）、Pb（II）的吸附平衡数据进行拟合,显示其吸附行为与Langmuir和Frundlich两种吸附等温方程式均有较好的相关性。研究从动力学角度证明适当的磁场处理对壳聚糖及其衍生物对过渡金属离子吸附性能有明显的强化作用。五、羟丙基壳聚糖亚铁离子配合物在水处理中应用的研究配制了壳聚糖衍生物水处理助剂,采用正交试验法研究其软化硬水的优化条件。结果表明:当水处理助剂用量0.5%,在pH10,温度20℃下,反应25min,能较有效地吸附硬水中的钙镁离子,可使水的硬度由265.52 mg/L（以CaCO₃计）下降到98.70 mg/L,钙镁离子除去率可达60%以上。展示壳聚糖作为硬水软化处理剂的应用前景。对羟丙基壳聚糖亚铁离子配合物吸附铜、铅离子的研究表明:添加量均为1%时,对含铜、铅离子初始浓度分别为1 mg/L、0.1 mg/L的水,吸附30min,其去除率分别达99.8%、78.8%。表明羟丙基壳聚糖亚铁离子配合物可做为吸附重金属离子的新型水处理剂。利用羟丙基壳聚糖亚铁配合物作为水处理剂结合生物处理方法,对屠宰废水进行处理,取得满意的实用效果。更多还原

【Abstract】 Chitosan（CS） , （1,4）-2-amino-2-deoxy-β-D-glucan, is the product of partial deacetylation from natural chitin.Recently, much attention has been paid to chitosan because it has excellent properties such as biocompatibility, non-toxicity, bioactivity and physicochemical property. There is a vast vista of application for chitosan in water treatment, chemical industry, textile, food and medicine industry. However, by its crystalline structure, the application is restricted in some respects. It is an effective step to improve the applied properties with the modification of chitosan. The studies on the modification of chitosan and the properties of its derivatives using physical fields（magnetic field and ultrasonic field） for rising the reaction speed and reaction yield. The basic investigative data were provided for the development on the new high efficiency water treatment agent. The main contents and results of this thesis are as follows:1. Study on the Complex Reaction of Chitosan and Fe（II） Enhancing with Magnetic TreatmentMangnetic technology was used to enhance the synthesis of chitosan-Fe（II）,mostly the reaction of chitosan and ammonium ferrous sulfate,then synthesizing chitosan- Fe（II） complex. The effects of power densities of magnetic field, magnetic treatment time, ratios of reactant, initial concentration of Fe2+, dosages of chitosan, temperature and pH value on the reactions were studied. The result showed that the coordination reaction could be enhanced by a constant magnetic fields with magnetic induction of 100 mT～150mT.The reaction rate and complex yield could be increased 23.0% and 24.0%under the optimized magnetic fields treatment conditions. The analysis showed that for the case of experiments, there was almost no influence on molecular weight, deacetylation degree and the basic structure of products by the treating with the magnetic field.2. Study on Etherification of Chitosan Enhancing with Ultrasonic FieldUltrasonic technology was introduced to study the complex reaction of chitosan with epoxypropane, the effects of power densities of ultrasonic field, ultrasonic irradiation time, ratios of reactant, temperature and pH value on the reactions were studied. The result showed that the reaction speed of the synthesis of O-（hydroxyl isopropy1） chitosan was quickened by the ultrasonic-assisted technology and the dosages of epoxypropane and catalyzer could be reduced.The experimental result of the optimumation for the preparation of O-（hydroxyl isopropy1） chitosan complex was as follow: the ratio of volumn of epoxypropane and catalyzer and the ratio of gram of chitosan is 10ml:0.8 ml:1g, at the temperature 60℃～70℃, radiating with ultrasound for 3 h, under a power ultrasound of 120kW. The improvement of obtain ratio and substitution degree was 13.6% and 12.9 %, respectively. The structure of the product was identified by iodoform reaction, Fourier infrared spectrum and X-ray diffractomer.3. Study on the Adsorptive Property of Hydroxylpropyl Chitosan-Fe（II） Complex Enhancing with Magnetic FieldThe magnetic field treatment technology was introduced in the researches of adsorption properties of hydroxylpropyl chitosan-Fe（II） complex. Three kinds of metal ions: Cr （VI）, Cu （II）, Pb （II） were selected. The study of adsorptive property of hydroxylpropyl chitosan-Fe（II） on the three metal ions under the constant magnetic field. The experimental result showed that adsorption effect could be influenced by power densities of magnetic field, metal ion pH value and initial concentration of solution. The absorptive quality and rate of the Cr （VI）, Cu （II）, Pb （II） by hydroxylpropyl chitosan-Fe（II） complex were both increased with the constant magnetic field intensity when magnetic induction from 200 mT to1000 mT.However, the acidity existed a adsorptive optimum value under pH4～pH5, and the initial concentration of metal ion solution would be controlled in 30mg/L～40 mg/L.4. Study on Adsorptive Kinetics of Hydroxypropyl Chitosan-Fe（II） ComplexThe adsorption kinetics were researched on chitosan and its derivatives on the three metal ions: Cr （VI）, Cu （II）, Pb （II） in magnetic field. The results showed the order of their adsorption properties for the three metal ions was Cu （II） > Pb （II） >Cr （VI）. Classical isothermal equations were used to fit the adsorption equilibrium data of chitosan and its derivatives on Cr （VI）, Cu （II） , Pb （II） and the experimental results showed that their adsorption behavior were interrelated well with Langmuir and Frundlich adsorption isothermal equation. The research showed that the suitable magnetic treatment could be enhanced significantly the adsorption properties of chitosan and its derivatives on matel ions according kinetic view.5. Study on Application of Hydroxypropyl Chitosan- Fe （II） Complex in Water TreatmentThe water treatment additive of derivative chitosan was prepared, the optimum conditions were researched for soften the hard water with the orthogonal experimental technique. The results showed that it could effective adsorb Ca2+ and Mg2+ in hard water with water treatment additive amount of 0.5%, with pH10, temperature at 20℃, reaction time for 25min, it could make water degree of hardness （by the CaCO3 amount） from 265.52 mg/L drops to 98.70 mg/L,Ca²⁺ and Mg²⁺ in hard water may be adsorbed by the rate of above 60%. Display using derivative chitosan as a hard water soften agent is effective and there are the very applications in the future.The adsorptive properties of hydroxypropyl chitosan-Fe（II） complex (HPCTS-Fe²⁺) for heavy metal ions were researched .The experiments showed that the removal efficiencies were 99.8%、78.8% respectively with using 1%（g/mL） of the HPCTS-Fe²⁺, pH5, initial concentration 1 mg/L Cu²⁺、0.1 mg/L Pb²⁺ respectively, absorption for 30min. It showed that HPCTS-Fe²⁺ might be used as a new high efficiency water treatment agent for absorbing heavy metal ions.Satisfactory results were also obtained in practical application of the abattoir wastewater treatment, hydroxypropyl chitosan-Fe（II） complex for water treatment agent combining with biological treatment method.更多还原