Selective Oxidation of Allylbenzene to Cinnamaldehyde over BiMoO _x -Loaded CoFeMoO _x Catalysts and Kinetic Analysis Including Oxygen Transfer of CoFeMoO _x Supports

The selective oxidation of olefins to unsaturated aldehydesoverBi molybdate catalysts is one of the most important reactions in petrochemicalprocesses. The lattice oxygen of Bi molybdate is believed to be involvedin the reaction, and lattice oxygen transfer is the rate-determiningstep at temperatures below 350 degrees C. Co and Fe are commonly addedto Bi molybdate catalysts to accelerate the reoxidation of the activesites by the lattice oxygen transfer associated with the redox reactionof Fe. Hence, the reaction rate expression should include latticeoxygen transfer, which has not been previously reported. In this study,Bi molybdate catalysts loaded on an Fe-containing-Co molybdate supportwere synthesized, and the selective oxidation of allylbenzene to cinnamaldehydewas performed. The experimental reaction rates were satisfactorilydescribed by the quasi-steady-state approximation of the lattice oxygenof the support surface. The high oxygen uptake ability of the supportwas found to be important for improving the catalyst activity.