Texture/morphology evolution of CeZrO/Al2O3 nanocatalyst via sono-precipitation design for preferential oxidation of carbon monoxide: influence of ultrasound irradiation power

Abstract

A series of CeZrO/Al2O3 nanocatalysts were synthesized via sono-precipitation method for utilization in oxidation of CO. The XRD results showed lower intensity of active phase peaks as the sonication power increased showing higher dispersions. SEM and TEM images showed the destruction of large particle agglomerates and superior dispersion of the CeZrO particles both on the surface and into the depth of support. BET-BJH results showed that the low surface area and pore volume of the CeZrO oxide approaches the alumina's area and higher pore volume by increasing the sonication power which reached 111 m2/g in 90 W sonicated nanocatalyst. The catalytic performance results with three different CO concentrations of 1, 2 and 4% proved the effectiveness of the ultrasound energy in successful conversion of the carbon monoxide in the gas stream. The 90 W treated sample reached the 98% CO conversion at 250 ºC and full conversion at 275 ºC.