Process Optimization and Kinetic study of Wet Peroxide Oxidation of Phenol in Wastewater over Mg-Al Nano Mixed Oxide

Abstract

The wet peroxide oxidation (CWPO) of phenol in the polluted water on Mg-Al nano mixed oxide was investigated and the optimization and kinetic of the process were studied. The nanocatalyst was characterized by XRD, FESEM, EDS and BET. The average crystallite size of 25 nm was estimated using Scherrer formula.FESEM images approved the catalyst comprised of spherical nanoparticles in the range of 94-130 nm. BET results indicated the mesoporous nanocatalyst (dpore=21 nm) has a specific surface area of 86.3 m².g^-1. The optimized conditions of the process resulted at initial concentration of phenol, reaction temperature, reaction time and hydrogen peroxide volume of 100 ppm, 60ºC, 55 min and 3 mL, respectively. The phenol degradation under the optimal conditions reached 85%. The result of the kinetic study indicated that the oxidation of phenol over Mg-Al nano mixed oxide follows the pseudo-first-order kinetics with a correlation factor of 0.94. The activation energy of phenol oxidation over the catalyst was determined to be 19.07 kJ.mol^-1. The Mg-Al mixed oxide is a cheap and green catalyst and could be prove to promising for the CWPO process.