【作者】 孙娅芳；

【导师】 贾殿赠； 王瑞英；

【作者基本信息】 新疆大学 ， 化学， 2010， 硕士

【摘要】 多金属氧酸盐是一类含有氧桥的多金属氧簇化合物,因其独特的结构在催化、磁性、非线性光学性质及抗病毒活性等方面具有广阔的应用前景。从环保的角度出发,离子液体在有机化学反应中作溶剂、萃取剂或催化剂构成复合催化体系以及新型功能催化剂,有着不易燃、热稳定性好、真空压很小(不易挥发)等优点。本论文将多金属氧酸盐及离子液体的优点相结合,选取Keggin结构的杂多酸与所合成的离子液体有机配体为原料,利用低热固相化学反应法合成了系列离子液体多金属氧酸盐,并将其用于作催化一元羧酸、二元羧酸、三元羧酸及不饱和羧酸与正丁醇酯化反应的催化剂,研究其催化性能,结果表明,带有磺酸基团的离子液体多金属氧酸盐对酯化体系有较好的催化活性。有机酯是重要的化工中间体,酯化反应催化剂有无机酸、固体超强酸和离子液体等,这些催化剂有的对设备产生强烈腐蚀和形成大量三废,有的价格昂贵,有的难以分离和回收。本论文采用低热固相化学反应法制备的离子液体多金属氧酸盐对酯化反应具有良好的催化活性,在一些酯化反应体系中开始为均相催化剂,反应结束后又可以沉淀出来,这使其与非均相催化剂有相似之处。离子液体多金属氧酸盐催化剂结合了均相和非均相催化剂的优点,有望解决催化剂分离回收利用等问题。更多还原

【Abstract】 Polyoxometalates, one type of well-known polynuclear metal-oxo clusters, have attracted considerable interest for their application in many materials of catalysis, magnetic materials, non-linear optical and antiviral activity owning to their unique structure. The use of room temperature ionic liquids (ILs) as solvent, catalysts, and extractive solvent for chemical reactions offers several advantages from this environmental perspective. They are non-flammable, thermally stable, exhibit negligible vapor pressure (non-volatile), and offer the potential for recyclability. We synthesize a series ionic liquid polyoxometalates (IL-polyoxometalates) for combining the advantages of polyoxometalates with ionic liquids by low-heating solid-state chemical reaction. We study the catalysis properties of the products in the esterification reaction of unitary, binary, tenary and unsaturated carboxylic acid and butanol using polyoxometalates as catalysts. The results demonstrate that IL-polyoxometalates are good catalysts for esterification reaction.Organic esters are important intermediates in chemical and pharmaceutical industries, and they are mostly produced by acid-catalyzed esterification reactions. Various mineral acids, solid super acid and ionic liquids, have been used as catalysts for esterification. However, these acids are extremely corrosive and contaminative and need to be neutralized at the end of the reaction. Furthermore, it is very difficult to separate and reuse the catalysts.The use of propane sulfonate (PS) functionalized IL-polyoxometalates for the esterification reaction is considered to be an effective approach. They could be used as homogeneous catalysts for many esterification reactions because of their good solubility in reaction media, and moreover, at the end of the reaction, the catalysts precipitated and could be recycled without any regeneration being required, just like a heterogeneous system. Thus, these catalysts combine the advantages of homogeneous with heterogeneous catalysis.更多还原