【作者】 邱竹；

【导师】 童张法；

【作者基本信息】 广西大学 ， 化学工艺， 2007， 硕士

【摘要】 高效、低成本进行有机溶剂脱水，特别是从含水的共沸物或近沸点物进行脱水，一直以来是化工生产中的研究热点。特别是脱除含水乙醇中少量水以制备无水乙醇吸引了众多研究者的目光。无水乙醇作为一种新兴能源、具有无污染、可再生等优点。生产无水乙醇符合我国可持续发展的能源政策。传统的方法制备无水乙醇能耗大、生产成本高、而且容易造成环境污染，人们一直在进行低能耗、低成本工艺的开发。吸附分离技术能耗低，其中吸附脱水材料的选择是关键。常见的脱水材料有分子筛类、生物质类材料等。然而分子筛类材料再生比较困难，生物质类材料耐热性能差，寿命不长。因此开发出一种低成本、低能耗、脱水能力强、再生容易的脱水材料以制备无水乙醇具有重要意义。本课题组研制出一种具有阴离子交换功能的碱性钙基膨润土及其制备方法。该膨润土层间的氢氧根除了具有阴离子交换功能外，还更易与水分子形成氢键。本工作把它作为脱水材料进行研究，通过单因素实验、正交试验考查了合成工艺条件对其脱水率的影响，在最佳工艺条件下，利用红外光谱、电镜扫描、X射线衍射和差示扫描量热仪等手段对脱水材料进行表征，并与木薯淀粉及分子筛脱水材料进行了比较。在应用研究方面，将该脱水材料应用于含水乙醇气相脱水试验，制得99.50wt％以上的无水乙醇。单因素实验、正交实验确定最佳工艺条件为：在本实验范围内活性白土与氧化钙用量的质量比为5：2、水土质量比为4、反应温度为60℃、反应时间为12hr。此工艺下所得产品在60℃时的脱水率达到12.1％；结构表征结果显示，碱性钙基膨润土脱水材料热稳定性好，层间距大，脱水速度快，脱水再生温度低，与淀粉和分子筛脱水材料相比较具有明显优势；固定床乙醇气相脱水试验表明，表观气速和床层温度对吸附过程有不同程度的影响，在试验范围内，含水乙醇蒸汽通过脱水材料最高可制得99.63wt％的无水乙醇，拓宽了膨润土的应用领域，为该材料的进一步开发利用提供了参考。更多还原

【Abstract】 Dehydratin in organic solvent with high efficiency and low cost is a hot area in the chemical industry, especially dehydration in azeotropic compounds. Removal of minimum water from ethanol to produce anhydrous ethanol attracts many researchers. As a new energy resource, bioethanol has non-polluting and reproductive properties. Anhydrous ethanol production accords with the energy policy of continuous development. Traditional methods of producing anhydrous ethanol spend too much energy. Researchers are on the way to find a low cost technology. Adsorption technology has a low energy consumption. The choice of anhydrous material is the key point. Molecular sieves and bio-materials are popular anhydrous materials. However molecular sieves are difficult to regenerate and bio-materials are bad in thermal stability. Therefore, it is important to produce anhydrous ethanol with a kind of anhydrous material which is cheap, low energy consumption, efficient, easy to regenerate.A kind of alkaline Ca-bentonite and production technology were presented by our item group. The OH~- in the interlayer has not only exchange function, but also the attachment with water. Alkaline Ca-bentonite is taken as anhydrous material in this work. The effects of preparation conditions for alkaline Ca-bentonite anhydrous material on its dehydration behavior were investigated. The optimized anhydrous materials were characterized by FT-IR, SEM, XRD and DSC. The application experiment in the ethanol vapor dehydration give 99.5 wt% ethanol.The optimized technology are obtained as follows: the mass ratio of activated clay and CaO is 5:2, the mass ratio of liquid to solid is 4, reaction temperature is 60℃, reaction time is 12 hr. Compared with molecular sieves and cassava starch , it shows that the dehydration behavior of alkaline Ca-bentonite is 12.1% at the 60℃which is higher than that of molecular sieves and equivalent to cassava starch. The structure characterization results indicate that alkaline Ca-bentonite is of good thermo-stability, easy regeneration and small adsorption heat. Furthermore, ethanol vapor dehydration experiment with fixed adsorption bed indicate that superficial velocity and temperature affected adsorption differently. Ethanol vapor via dehydration material can give 99.63 wt% ethanol. The application area of bentonite is broadened. A reference for this material application is presented .更多还原