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

• Published in: Applied catalysis. B, Environmental Environmental, 2014-06, Vol.152-153, p.28-37
• Main Authors: Maqbool, Muhammad Salman, Pullur, Anil Kumar, Ha, Heon Phil
• Format: Article
• Language: English
• Subjects: Beneficial sulfation; Catalysis; CeO2/TiO2; Cerium(III) sulfate; Chemistry; Exact sciences and technology; General and physical chemistry; NH3-SCR; NOx conversion; Theory of reactions, general kinetics. Catalysis. Nomenclature, chemical documentation, computer chemistry
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2014.01.017

•Sulfation of Sb-V2O5–CeO2/TiO2 catalyst formed cerium sulfates preferentially.•Sulfation at 500°C could improve its acidity at the expense of NO adsorption.•S500 catalyst produced Ce2(SO4)3 which is more active and favorable for NH3-SCR.•Sulfation at high temperature increased chemisorbed oxygen and reducible species. 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 2h. We have elucidated the real insights via nature-property relationships of the species formed at various SO2 pretreatment temperatures (T=300, 400 and 500°C) with the help of advanced characterization techniques such as X-ray diffraction (XRD), temperature programmed reaction (NH3-TPD, NO-TPD and H2-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°C led to the maximum favorable sulfation with cerium(III) sulfate as the major surface species.