【作者】 陈仁菊；

【导师】 肖凯军；

【作者基本信息】 华南理工大学 ， 制糖工程， 2011， 硕士

【摘要】 膜分离技术是一种经济环保高效的新型的分离技术,而智能膜材料具有响应环境的智能型特点,成为膜分离技术应用研究的热点领域。温度感应型智能膜是一种新型膜材料,在外界温度变化时,膜能够响应外界温度的改变,膜的结构与性能发生相应的有规律的变化,在可控释放、智能控制等方面具有广泛的应用。本文研究了接枝法制备智能复合膜和相变法制备智能膜的工艺参数,研究两种工艺条件下的微观结构、膜分离特及其温度响应特性,并首次利用温度响应智能膜开展纳米孔径吸收二氧化碳气体的吸收、传质等特性的研究,建立相关数学模型。本论文研究的主要内容和结果如下:1.开展碱改性-接枝法制备温度响应聚偏氟乙烯（PVDF）复合膜的制备工艺的研究。首先对PVDF平板膜进行强碱改性,然后采用接枝法引入PNIPAM单体,研究不同交联剂浓度、温度对膜性能的影响,制备出具备温度响应特性的智能膜。红外光谱分析结果显示已经接枝上了温敏基团,实验结果表明最佳工艺条件为:交联剂（MBAA）浓度0.02mol/L,接枝率7%,交联反应温度50℃⁶0℃。2.进行相转变法制备温度响应的PVDF膜的研究。用强碱和接枝方法对PVDF粉末进行改性,通过相变法制备出具备温度响应特性的智能膜。研究了单体浓度、交联剂浓度、溶剂种类、凝固浴组成对其温度响应特性的影响。结果表明较理想的工艺流程参数为:交联反应的温度60℃,单体浓度12%¹4%,凝固浴中乙醇与水的体积比为3:7,溶剂中N,N-二甲基甲酰胺与二甲基亚砜按1:1混合。对其性能的研究发现,其具备较好的选择透过性、耐污染性、温度响应性等。3.研究具有温度感应特性的PVDF中空纤维膜吸收器对二氧化碳的吸收特性和传质规律。采用碱改性-接枝法制备出的的智能膜材料,加工成膜组件制备成温度感应型中空纤维膜吸收器。以二氧化碳为温室效应的代表气体,以NaOH为吸收液,膜吸收器较佳的工艺参数为:吸收液浓度为0.4mol/L,吸收液流量为16L/h,气体流量为250L/h,操作温度为室温25℃,气液两相相对流动方式采用逆流方式。此时,二氧化碳的吸收率接近100%。而对二氧化碳气体吸收过程中传质的研究得出,总传质系数在KG = 17.5²6.3×10⁶ mol·m^-3·s^-1·kPa^-1,和传质通量N_CO2 =3.8⁷.6×10⁵ mol·m·s^-1·L^-1。结合影响智能膜吸收器对二氧化碳吸收率及传质系数的主要因素（气体流量、吸收液流量、温度、吸收液浓度等）,建立相关的数学模型。建立的数学模型能较好的描述了各相关因素的影响,且影响因素的大小顺序如下:吸收液浓度>吸收液流量>温度>二氧化碳气体流量。关于二氧化碳吸收率的回归方方程:关于总传质系数的回归方程:关于二氧化碳传质通量的回归方程:更多还原

【Abstract】 Membrane Separation Technique is very economic, environmentally friendly, efficient. Intelligent membrane materials has become the hotspot areas in application of membrane separation technology, as it can repsonse to the changes of environment . Temperature responsive membrane is a new membrane material.The structure and properties of the membrane changed regularly according to the changes of environment temperature, so this membrane used widely in controlled release, intelligent control and etc.In this paper, we studied the technological parameter of preparing the intelligent composite membrane by grafted method and preparing the intelligent membrane by phase change method, and we also studied the microscopic structure of the membrane, membrane separation, and temperature response characteristics under this two process conditions. In this paper, we use the temperature intelligente membrane in carbon dioxide gas absorbing, mass transfer research by nanometer aperture membrane, established relevant mathematical model at the same time.The main contents and the results of this paper as follows:（1） Carry out the research of preparation process of temperature responding polyvinylidene fluoride（PVDF） composite intelligent membrane by alkaline modification - grafted method . PVDF flat membrane was modified with the method of strong caustic grafting modification, PNIPAM was grafted onto the PVDF basement membrane, and the thermo-responsive intelligence membrane was prepared. Infrared spectral analysis results showed that temperature sensitive group has been grafted onto PVDF, experimental results showed that the optimum technological conditions is: crosslinking agent （MBAA） concentration 0.03mol/L, grafted rate of 7%, cross-linking reaction temperature 50℃ 60℃. The result also showed that it has strong resistance to pollution, very selective, and good temperature responsive. by study is performance.（2） Carry out the research of temperature response PVDF by Phase change method .PVDF powder was modified with the method of strong caustic modification and graft, and thermo-responsive intelligente membrane was prepared by phase change. Factors which can influence the temperature responsive characteristics of thermo-responsive intelligence membrane was reseached such as monomer concentration, crosslinking agent concentration, the kind of solvents, coagulation bath composition. The results showed that ideal process parameters for this experiment is: crosslinking reaction temperature 60℃, monomer（PNIPAM） concentration 12% 14%, the concentration of ethanol in coagulation bath is 30%, the solvent is made up by N, N - DMF and dimethyl sulfoxide with 1:1 ratio.（3） Studied the CO₂ absorption characteristics and mass transfer rule temperature repsonse PVDF hollow fiber membrane absorber. The intelligent membrane materials was prepared by alkaline modification, temperature responsive intelligent hollow fiber membrane absorber was prepared by equip this intelligent meterial into membrane module. Using carbon dioxide for representative greenhouse gases, and use NaOH as absorbing liquid, the result showed that the ideal process parameters for this process is : absorbing liquid concentration is 0.4 mol/L, absorbing liquid flow is 16L/h, gas flow is 250L/h, operating temperature temperature is 25℃, gas-liquid downstream flow.And under such conditions, the absorption rate carbon dioxide is close to 100%, total mass transfer coefficient is KG = 17.5²6.3×10⁶ mol·m^-3·s^-1·kPa^-1 , and the mass transfer flux is about N_CO2 =3.8⁷.6×10⁵ mol.m.s^-1.L^-1. Combine the main factors that influence on carbon dioxide absorption rate and the mass transfer coefficients （gas flow, absorbing liquid flow, temperature, absorbing liquid concentration etc）, establish relevant mathematical model. Established mathematical model can better describes each related factors, and the order of the influence factors are as follows: absorbing liquid concentration >absorbing liquid flow >temperature > carbon dioxide gas flow.The mathematical model showed as follows.Regression equation about carbon dioxide absorption rate :Regression equation about total mass transfer coefficient:Regression equation about total mass transfer flux:更多还原