Characterization and performance of Pt-Pd-Rh cordierite monolith catalyst for selectivity catalytic oxidation of ammonia.

This work considers the oxidation of ammonia (NH(3)) by selective catalytic oxidation (SCO) over a Pt-Pd-Rh cordierite monolith catalyst in a tubular fixed-bed flow quartz reactor (TFBR) at temperatures between 423 and 623K. A Pt-Pd-Rh cordierite monolith catalyst was prepared by incipient wetness impregnation with aqueous solutions of H(2)PtCl(6), Pd(NO(3))(3) and Rh(NO(3))(3) that were coated on cordierite substances. The catalysts were characterized using XRD, PSA and SEM. The experimental results show that around 99.0% NH(3) removal was achieved during catalytic oxidation over the Pt-Pd-Rh cordierite monolith catalyst at 623K with oxygen content of 4%. N(2) was the main product in the NH(3)-SCO process over the Pt-Pd-Rh cordierite monolith catalyst. These results also verify that the Pt-Pd-Rh metals on cordierite monolith surfaces, resulting in the formation of catalytically active sites at the metal-support interface in the reduction of NH(3) in the process. Copyright 2010 Elsevier B.V. All rights reserved.