Kinetic studies and Mechanism Evolution of the Ammoxidation of 3-picoline Over V2O5/ZrO2 Catalyst

Abstract

A kinetic investigation of the ammoxidation of 3‐picoline to 3‐cyanopyrdine has been studied over V2O5/ZRO2 Catalyst in a differential flow reactor in the temperature range 573‐683 K. The partial pressures of 3‐picoline, oxygen and ammonia were varied and rates were measured for the formation of 3‐cyanopyridine. Kinetics studies reveal that the mechanism of the reaction is of the “Redox” type. The rate equation deduced, assuming a study state involving a three stage oxidation‐reduction process, represented the data most satisfactorily for conversion of 3‐picoline to nicotinonitrile. Catalysts have been characterized using IR, XRD, ESR, Surface area and ammonia desorption methods with a view to understanding the structure and nature of bonding over the surface of the catalyst. A tentative mechanism of the process has been suggested.

Effect of supports on the structure and activity of vanadium-chromium oxide catalysts for ammoxidation of 3-picoline

“…Therefore, the redox properties strongly influence the catalytic performance. According to a study by Radheshyam et al [23], the activation energy of the reduction step is almost three times higher than that of the reoxidization step in the ammoxidation of 3-PIC over V2O5/ZrO2 catalyst. These findings indicated that the more reducible the vanadium in the catalyst is, the more active the catalyst is.…”