화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.35, No.8, 3234-3242, 2010
Preferential oxidation of carbon monoxide in simulated reformatted gas over PtAu/Ce(x)Zn(y)O(2) catalysts
A series of Pt-Au catalysts prepared by co-precipitation (CP) and single step so-gel (SSG) methods was investigated for selective CO oxidation. The characteristics of the prepared catalysts were determined by XRD, BET surface area, SEM, H(2)-TPR, chemisorption analysis, and FTIR. The simulated reformatted gas consisted of 1% CO, 1% O(2), 0% to 10% H(2)O, 0-20% CO(2), and 40% H(2) in He balance. The operating temperature range was varied from 50 degrees C to 190 degrees C at atmospheric pressure. The experimental results elucidated that the catalytic preparation method had a significant effect on the catalyst characteristics and its activity. The catalytic performance over PtAu/Ce(1)Zn(1)O(2) prepared by co-precipitation was higher than that of PtAu/CeO(2) and PtAu/ZnO because of the incorporation of Ce(4+) ions and the Zn(2+) ions in the lattice. To encourage better catalytic performance, the catalysts should be calcined at 500 degrees C for 5 h and pretreated in a H(2) atmosphere. The CO conversion for the single- and double-stage reaction was reduced when adding water vapor and CO(2) to the feedstream; the water vapor and CO(2) molecules compete for the adsorption with CO on the active sites of the catalysts. During the deactivation test for 60 h, the CO conversion and selectivity are maintained. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.