改性硅胶固载席夫碱配合物的制备及其催化性能研究

发布时间：2018-01-10 22:00

本文关键词：改性硅胶固载席夫碱配合物的制备及其催化性能研究　出处：《北京服装学院》2017年硕士论文　论文类型：学位论文

【摘要】：席夫碱金属配合物是非官能化烯烃环氧化反应中的一种高效催化剂,但它有很多缺点,比如催化剂和产物难以分离、无法重复使用、稳定性不高、对环境污染、在氧化条件下容易聚合等缺点,这些缺点限制了其在工业上的大规模使用,近年来,将均相催化剂固载到无机或有机载体上制备多相催化剂受到广泛关注。本文首先选用了(3-环氧乙基甲氧基丙基)三甲氧基硅烷和氯丙基三氯硅烷对羟基化的硅胶进行改性,以水杨醛、邻苯二胺、2,4-二羟基苯甲醛、3,5-二叔丁基水杨醛、3,4-二氨基吡啶及过渡金属盐等原料合成共4种席夫碱中间体及salen型配体,简化反应路线,提高反应效率,用核磁共振仪、电喷雾高分辨质谱等手段对所得产品进行了结构表征。合成第二种配体时,原料水杨醛室温下为液体,发现在超声条件下,仅用少量的溶剂,室温反应时间0.5h情况下就能得到较好的产率,达到75%。通过化学接枝合成了三类负载型salen金属配合物催化剂,通过FT-IR,ICP-AES和XRD等对其进行了结构表征。通过ICP-AES检测,三种负载催化剂的金属锰的上载量分别为:A为0.68mmol/g,B为1.05 mmol/g,C为0.72mmol/g。将制备的三类固载型催化剂应用于催化过氧化氢氧化苯乙烯的反应,通过所有单因素实验数据表明,仅探究苯乙烯的转化率,催化剂性能优异顺序为BAC,仅探究环氧苯乙烷的选择性,催化剂性能优异顺序为CAB,若综合考虑底物转化率和产物的选择性,对于催化剂A,B,C,最佳反应温度应分别为60℃,60℃,50℃,反应时间应分别为4h,5h,5h,氧化剂过氧化氢的量与均为底物苯乙烯的3倍,为后续正交试验设计,确定最佳反应条件提供依据,同时,三种催化剂均能重复使用4次以上催化活性和选择性没有明显降低。
[Abstract]:Schiff base metal complexes is an efficient catalyst for the epoxidation of unfunctionalized olefins, but it has many disadvantages, such as the catalyst and the product is difficult to be separated, can not be reused, stability is not high, the environmental pollution, the shortcomings of easy polymerization under oxidizing conditions, these shortcomings limit its large-scale use. In the industry in recent years, the homogeneous catalyst immobilized to the inorganic or organic carrier for preparing heterogeneous catalysts has attracted extensive attention. This paper chooses a (3- epoxy ethyl methoxy propyl trimethoxysilane) and three chloro silane on 3-chloropropyl hydroxylated silica gel was modified by salicylaldehyde two, benzene amine, 2,4- two hydroxy benzaldehyde, 3,5- di Ding Jishui Yang Quan, 3,4- two amino pyridine and transition metal salts such as raw material for the synthesis of 4 kinds of Schiff base intermediates and salen ligands, simplified reaction routes, improve the reaction efficiency, using nuclear magnetic resonance spectrometer, High resolution electrospray mass spectra of the products were characterized. The synthesis of second kinds of ligands, the raw material of salicylaldehyde liquid at room temperature, found under the condition of ultrasound, with only a small amount of solvent, reaction time under the condition of 0.5h at room temperature can get better yield reached 75%. by chemical grafting synthesis of three kinds of load type salen Metal Complexes Catalysts by FT-IR, characterized by ICP-AES and XRD. ICP-AES detection, three kinds of catalyst loading amount of metal manganese were: A 0.68mmol/g, B 1.05 mmol/g, three C 0.72mmol/g. the catalyst used in catalytic oxidation of styrene solid hydrogen peroxide supported by all reaction, single factor experiment data show that only on the conversion of styrene and the excellent performance of the catalyst in the order of BAC, only selective inquiry epoxyethylbenzene, forcing agent performance excellent Shun The order of CAB, if considering the substrate conversion and product selectivity, the catalyst A, B, C, respectively. The optimum reaction temperature 60 C, 60 C, 50 C, reaction time was 4h, 5h, 5h, H2O2 and the amount of substrate are styrene 3 times orthogonal experimental design for the follow-up, the optimum reaction conditions provide the basis, at the same time, three kinds of catalysts can be reused 4 times without significant loss of catalytic activity and selectivity.

【学位授予单位】：北京服装学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O641.4;O621.25

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