Journal of Colloid and Interface Science, Vol.581, 427-441, 2021
Understanding the high performance of an iron-antimony binary metal oxide catalyst in selective catalytic reduction of nitric oxide with ammonia and its tolerance of water/sulfur dioxide
YIn recent years, Fe-based catalysts for the selective catalytic reduction of NO with NH3 (NH3-SCR) have been attracting more attention. In this work, a novel Fe-Sb binary metal oxide catalyst was synthesized using the ethylene glycol assisted co-precipitation method and was characterized using a series of tech-niques. It was found that the catalyst with a molar ratio of 7:3 (Fe:Sb) displayed the best NH3-SCR activity with 100% conversion of NOx (nitrogen oxides) over a wide temperature window and with good resistance to H2O + SO2 at 250 degrees C. The X-ray photoelectron spectroscopy (XPS) and in situ diffused reflectance infrared Fourier transform spectroscopy (in situ DRIFTS) of NOx adsorption results suggested that strong electron interactions between Fe and Sb in Fe-O-Sb species existed and electrons of Sb could be transferred to Fe through the 2Fe(3+) + Sb3+ <-> 2Fe(2+) + Sb5+ redox cycle. The introduction of Sb significantly improved the adsorption behaviour of NOx species on the Fe0.7Sb0.3Ox surface, which benefitted the adsorption/transformation of NOx, thereby facilitating the NH3-SCR reaction. In addition, the Fe0.7Sb0.3Ox catalyst demonstrated a good tolerance of H2O and SO2, since the decomposition of NH4HSO4 on the catalyst surface was promoted by the introduction of Sb. (C) 2020 Elsevier Inc. All rights reserved.