芦苇叶模板钴掺杂材料和Co-MCM-41的制备及其催化氧化苧烯

【作者】 姚志昂；

【导师】 王伟； 王家强；

【作者基本信息】 云南大学 ， 物理化学， 2012， 硕士

【摘要】 香芹酮是植物精油中的主要成分,广泛应用于食品工业,特别是牙膏、口香糖、饮料的香精中,它也是合成其它芋烯含氧衍生物的重要中间体。因此,它的合成是一个重要的有机化学反应。由于工业合成香芹酮的方法存在易腐蚀设备、污染严重等缺点,近年来出现很多利用金属盐或金属配合物负载的介孔材料催化合成香芹酮的新方法,研究较多的是用介孔材料负载贵金属离子或者变价金属配合物。模板技术在介孔材料的合成中一直占据着重要地位,近年来,利用廉价、资源丰富、环境友好的生物模板合成孔状无机材料已经引起人们的普遍关注。云南是植物王国,有很丰富的植物资源,为生物模板选择提供了得天独厚的条件。本文选择湿地植物芦苇的叶子作为模板,以正硅酸乙酯(TEOS)为硅源,通过不同方法制备了过渡金属钴掺杂的二氧化硅(Co-SiO2)材料。通过改变材料的合成过程、焙烧方法、材料的焙烧温度及金属的掺杂比例等条件,得到了一系列过渡金属钻掺杂的生物模板材料,对所得材料进行了N2等温吸附-确附、X射线衍射法(XRD)、扫描电子显微镜(SEM)、X射线荧光光谱(XRF)等检测,表征了材料的内部和表面结构。将上述材料制备的催化剂用于芋烯的液相催化氧化反应,同时探讨了不同类型催化剂、不同处理方法催化剂、氧化剂、溶剂及溶剂用量、反应温度、反应时间、催化剂的焙烧温度、催化剂中金属掺杂比例等对催化反应的影响,反应产物用毛细管柱气相色谱进行检测,获得了最佳反应条件,并研究了催化剂的使用寿命。实验表明,在优化反应条件下,芋烯的转化率达100%,香芹酮的选择性为40.0%,香芹酮的得率达到40.0%。用水热法合成的Co-MCM-41,用其催化氧化芋烯,探讨了催化剂、氧化剂、溶剂及用量、反应温度等因素的影响,获得了优化反应条件,在该优化反应条件下,芋烯的转化率达到48.5%,香芹酮选择性达到54.5%。更多还原

【Abstract】 Carvone is one of the main component of plant essential oils, which is widely used in food industry, in particular, is for toothpaste, chewing gum, beverages, flavors, it is also an important intermediate in the synthesis of oxygenated derivatives of limonene.Therefore, its synthesis is an important organic chemical reaction.The industrial synthesis of carvone exists some defects such as corrosive equipment and serious pollution.Recently there are many reports on the synthesis of carvone used new materials as catalysts,such as metal salts and metal complexes loaded mesoporous materials.Most research are focused on the noble metal and Variable divalent metal compelxes which were supported by the mesoporous materials.The synthesis of mesopurous materials using templates has been playing an important role in the development of mesopurous materials.Recently,bio-templates have attracted considerable attention for the syntheses of porous inorganic materials, because they are generally inexpensive, abundant, environmentally benign, moreover, they can provide a novel strategy.Yunnan is very rich in plant resources,in this article,we select the wetland plant reed as the object of the study and choose its leaves as the bio-template.With bio-templates such as reed leaves,silica source such as TEOS, transition metal cobalt doped silica-based mesoporous materials(Co-SiO2) were synthesized by different methods.A series of transition metal cobalt doped silica-based mesoporous materials were obtained by adjusting the preparation process,the conditions of the calcination treatment of the material,the calcination temperature of the materials,the amounts of the transition metal.The samples were characterized by a combination of various physicochemical techniques, such as N2physisorption,,scanning electron microscopy (SEM) and X-ray fluorescencediffuse reflectance(XRF).For the first time,we use the obtained Co-SiO2as catalysts for the liquid phase oxidation of limonene under mild conditions.In order to obtain the optimum reaction conditions,the effects of some parameters were investigated,such as the kinds of the catalysts and oxidants,the amounts and types of the solvent,the reaction time and temperature,the calcination temperature of the catalysts,the doped amounts of the transition metal.After the reaction,the mixture was detected by capillary column Gas chromatograph(GC).And,of course,we had also investigated the life span of the catalysts. According to the experiments data,under the optimum reaction conditions,the conversion of limonene was100%,the selectivity of carvone was40%,the yeild of carvone was achieved at40%.The synthesis of Co-MCM-41was conducted by a process,then,using it as the catalyst of the oxidation of limonene.Under the optimum conditions,the conversion of limonene was48.5%,the selectivity of carvone was54.5%.更多还原