Novel sulfation effect on low-temperature activity enhancement of CeO2-added Sb-V2O5/TiO2 catalyst for NH3-SCR

Abstract

Sulfur dioxide (SO2) is considered as a poisoning gas for NH3-SCR catalysts under real time conditions. However, it has revealed an obvious beneficial effect on the activity of CeO2 containing catalysts. Hereby we report the applied research in sulfation effect on low-temperature activity enhancement of CeO2 modified, Sb2O3-V2O5-TiO2 catalyst system pretreated with SO2 under oxidizing conditions at different temperatures for 2 h. We have elucidated the real insights via nature-property relationships of the species formed at various SO2 pretreatment temperatures (T=300, 400 and 500 degrees C) with the help of advanced characterization techniques such as X-ray diffraction (XRD), temperature programmed reaction (NH3-TPD, NO-TPD and H-2-TPR), BET surface area, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS). Our results indicated that SO2 pre-treatment at 500 degrees C led to the maximum favorable sulfation with cerium(III) sulfate as the major surface species. (c) 2014 Elsevier B.V. All rights reserved.