Imine Oxidation Catalyzed by Zinc Hydroxyapatite: Kinetic Studies

Abstract

The synthesis of N,N‐diphenylformamide from N‐benzylideneaniline and urea hydrogen peroxide is investigated using a zinc hydroxyapatite (ZnHAP) catalyst. It was found that the catalyst resulted in the highest activity of 91 % conversion and 40 % selectivity at 130 °C in 2 h. A kinetic model was validated by Langmuir‐Hinshelwood‐Hougen‐Watson (LHHW) at different temperatures and the absence of mass transfer resistance was proved by the Weisz Prater criterion. Effect of different catalysts, catalyst loading, temperature, mole‐ratio, and speed of stirring was studied. The as‐synthesized catalyst is characterized by FTIR, BET nitrogen adsorption‐desorption, TEM, EDX, TPD‐NH3, XPS, ICP‐MS and XRD. ZnHAP catalyst was found to be stable up to three recycles with no loss in activity.