LaFeO3催化剂在木质素湿法氧化合成芳香醛反应中的活性与稳定性

利用溶胶-凝胶法制备了钙钛矿型复合氧化物LaFeO3, 利用X射线衍射、扫描电子显微镜、 X射线光电子能谱和N2吸附等表征手段考察了所制备样品的结构、形貌、表面物种和比表面积,并将其作为催化剂用于木质素湿法氧化合成芳香醛的反应中. 结果表明,该催化剂具有较高的活性和稳定性. 在适当的反应条件下, LaFeO3催化剂能显著提高木质素的转化率以及各芳香醛的产率,紫丁香醛的产率提高幅度大于香草醛和对羟基苯甲醛,紫丁香醛的最大产率是无催化剂反应时的1.85倍. 催化剂连续使用5次后仍能保持较高的活性,且体相结构没有发生明显的变化.

Activity and Stability of LaFeO3 Catalyst in Lignin Catalytic Wet Oxidation to Aromatic Aldehydes

The perovskite-type oxide LaFeO3 catalyst was prepared by the sol-gel method. The structure,shape,particle size,surface species,and specific surface area of the catalyst were characterized by X-ray diffraction,scanning electron microscopy,X-ray photoelectron spectroscopy,and N2 adsorption.The catalyst was used for wet oxidation of lignin to aromatic aldehydes and showed high activity and stability.Compared with a non-catalytic process,lignin conversion and yield of each aromatic aldehyde increased significantly,among which the yield of syringaldehyde was the highest.The maximum yield of syringaldehyde was 1.85 times that of the non-catalytic process.The activity and perovskite-type structure of the LaFeO3 catalyst almost remained unchanged after five successive operations.