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将奎宁与Keggin结构磷钼钒杂多酸结合制备出一种新颖的多相苯羟基化杂化催化剂,采用傅里叶变换红外光谱、紫外-可见光谱、X射线衍射、扫描电镜、热重、N2吸附-脱附和CHN元素分析等表征手段对催化剂进行了分析.结果表明,该催化剂是一种具有较高比表面积和孔体积的半无定形有机杂多酸盐.在H2O2为氧源的苯羟基化反应中,杂化催化剂引导了液-固两相催化体系,表现出较高催化活性和重复使用稳定性.催化剂中奎宁与杂多阴离子间的氢键和电子相互作用赋予了其高熔点和难溶性,而高比表面积和因奎宁而改善的杂多阴离子的氧化还原性是其获得优异催化性能的主要原因.这为多相苯羟基化反应提供了一种新的且制备便捷的基于多金属氧酸盐的高效催化剂.
A novel heterogeneous benzene hydroxylation hybrid catalyst was prepared by combining quinine with Keggin phosphomolybdovanadophosphoric acid. Fourier transform infrared spectroscopy, UV-Vis, X-ray diffraction, scanning electron microscopy, thermogravimetry , N2 adsorption-desorption and CHN elemental analysis were used to characterize the catalyst.The results showed that the catalyst was a semi-amorphous organic heteropoly acid salt with high specific surface area and pore volume.When H2O2 was used as oxygen source In the benzene hydroxylation reaction, the hybrid catalyst leads to the liquid-solid two-phase catalytic system, which exhibits high catalytic activity and repeated use stability. The hydrogen bonding and electronic interaction between the quinine and the heteropolyanion give the High melting point and poor solubility, while the high specific surface area and the redox properties of heteropolyanion improved by quinine are the main reasons for its excellent catalytic performance.This provides a new and promising method for the heterogeneous benzene hydroxylation Easy and efficient polyoxometallate based catalyst.