SBA-15固载磷钨酸催化剂的制备及催化性能  

Preparation of Heterogeneous Mesoporous Silica-Supported 12-Tungstophosphoric Acid Catalyst and Its Catalytic Performance

作　　者：郭红起 毛明富 倪中斌 陈明清 刘士荣 

机构地区：[1]江南大学化学与材料工程学院,江苏无锡214122

出　　处：《分子催化》2011年第6期496-502,共7页Journal of Molecular Catalysis(China)

基　　金：国家自然科学基金资助项目(20876070)

摘　　要：以SBA-15和氨基功能改性的SBA-15/NH2为载体,采用浸渍法制备了固载磷钨酸催化剂,通过FT-IR光谱,Raman光谱,XRD衍射分析,N2-吸附脱附实验,TEM和NH3-TPD等手段对催化剂进行表征.结果表明,磷钨酸在两种载体上均保持Keggin结构,载体的介孔结构没有明显破坏.在高固载量情况下,磷钨酸在SBA-15载体上发生晶相聚集,介孔孔道发生堵塞使比表面积、孔容和孔径明显减小.在SBA-15/NH2载体上,磷钨酸与载体发生酸碱作用,能够均匀分散于SBA-15/NH2的孔道中,但催化剂酸性有所降低.考察了相同固载量的两种催化剂对苹果酯合成反应的催化活性,结果表明,以SBA-15/NH2为载体的催化剂具有良好的重复使用性能.12-tungstophosphoric acid was supported on SBA-15 and amine-modified SBA-15 by impregnation. The structure and properties of the catalyst were characterized by FT-IR spectroscopy, X-ray diffraction, N2 adsorptiondesorption, TEM, Raman spectra and NH3-TPD technology. The result confirmed the mesostructure for SBA-15 and the Keggin structure of the heteropolyanions was preserved. However, aggregation oeeured in the high loading, and because of the pore blockage, the BET surface area, pore volume and pore diameter decreased obviously. The tungstophosphoric acid can disperse in the pore of the support SBA-15/NH2, but the acidity of the catalyst reduced. The catalytic activities of the catalysts were evaluated for the esterification reaction of ethyl acetoacetate and ethylene glycol . and the catalysts supported on amine-modified SBA-15 show excellent reusability and selectivity.

关 键 词：SBA-15 氨基改性 磷钨酸 固载催化剂 苹果酯 

分 类 号：O643.32[理学—物理化学]