APPLICATION OF LaBO3 (B = Fe, Co, Mn) IN LIGNIN CATALYTIC WET OXIDATION CONVERSION TO SELECTIVE PRODUCTION OF AROMATIC ALDEHYDES

In order to find an efficacious and lower-price heterogeneous catalyst for the catalytic wet aerobic oxidation of lignin, the perovskit-type oxide LaBO(3) (B = Fe,Co,Mn) catalysts were prepared by the sol-gel method and it was applied for the catalytic wet aerobic oxidation of lignin. The structure, surface species, reducibility and specific surface area of catalysts were characterized by XRD, XPS, TPR of H2. The catalysts showed high activity, compared with non-catalyst process, and lignin conversion and yield of each aromatic aldehydes were increased significantly. The following activity scale was found : LaCoO(3) > LaMnO(3) > LaFeO(3). The result indicated that the catalytic oxidation activity was related with the content of the surface absorbed oxygen and redox ability of B-site ion.