Ultrasonic-assisted fabrication and catalytic activity of CeZrAl oxide-supported Pd for the purification of gasohol exhaust

CeZrAl oxides (CZA) using as the support of Pd catalyst for purification of gasohol exhausts are synthesized by co-precipitation assisted by ultrasonic vibration. CZA are characterized by surface analysis, X-ray diffraction, temperature-programmed reduction by hydrogen, oxygen storage capacity (OSC), and X-ray photoelectron spectroscopy. The results show that ultrasonic vibration promotes the formation of smaller, more uniform pores in CZA, which is beneficial to the dispersion of Pd species. Ultrasonic vibration can also improve the OSC and uniformity of the composition of CZA on its surface and in bulk. Catalytic tests demonstrate that ultrasonic treatment of CZA widens the window of the full use of oxygen from 0-0.64% to 0-1.16% of Pd-CZA catalysts in the purification of gasohol exhaust, and decreases the light-off temperature of ethanol, propane, and carbon monoxide by 30, 28, and 24 C, respectively. Moreover, the interaction between Pd species and CZA can enhance the reaction of NO with propane and ethanol. (C) 2013, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.