NO reduction by propane over monolithic cordierite-based Fe/Al2O3 catalyst: Reaction mechanism and effect of H2O/SO2. (15th October 2016)

• Record Type: Journal Article
• Authors: Zhou, Hao; Su, Yaxin; Liao, Wenyu; Deng, Wenyi; Zhong, Fangchuan
• Is Part Of: Fuel. Volume 182(2016)
• Page Start: 352
• Page End: 360
• Publication Date: 2016-10-15
• Subjects: Fe/Al2O3 -- SCR of NO -- C3H8 -- H2O -- SO2; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2016.05.116
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: Fe/Al2 O3 /cordierite catalyst for NO reduction with C3 H8 . The strong and reversible inhibition effect of H2 O on NO2 /NO3 − species, while the negligible effect on acetate/formate species. The weak inhibition effect of SO2 on NO2 /NO3 − species, although the enhancement of the acetate/formate species. A mechanism of the C3 H8 -SCR reaction over Fe/Al2 O3 /cordierite catalyst was proposed. Abstract: The selective reduction of NO by C3 H8 and the sensitivity to H2 O and SO2 have been studied over monolithic cordierite-based Fe/Al2 O3 catalysts, which were prepared by the sol–gel and impregnation method. The catalysts were investigated by N2 adsorption, X-ray diffraction (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) techniques. Results showed that NO reduction was more than 90% in the absence of oxygen at 500 °C and in the presence of oxygen at 600 °C respectively. In a continues test of 12 h at 600 °C, 0.02% of SO2 caused an irrecoverable decrease of NO conversion from 94% to 85% and 2.5% of H2 O caused a drop of NO conversion from 86% to 56%, while NO conversion totally recovered when H2 O was removed. The catalysts lost 15% of the initial activity after a hydrothermal treatment due to the agglomeration of iron oxide nanorods. Sulphidation treatment caused about a loss of 30% of the initial activity because of the deposited SO4 2− species. In situ study by DRIFTS indicated that coexisting H2 O influenced the formation NO2 adspecies and unidentate nitrate, while SO2 slightly inhibited the formation of NO2 /NO3 − species, but promoted the formation of acetate/formate species during NO reduction by C3 H8 . Based on the results, a preliminary mechanism was proposed and discussed. The results may help understand the fundamental performance of monolithic cordierite-based Fe/Al2 O3 catalysts and provide some reference for SCR-HC catalyst design.