Journal of Hazardous Materials, Vol.260, 104-111, 2013
Selective catalytic oxidation of H2S over iron oxide supported on alumina-intercalated Laponite clay catalysts
A series of iron oxide supported on alumina-intercalated clay catalysts (named Fe/Al-Lap catalysts) with mesoporous structure and high specific surface area were prepared. The structural and chemical properties were studied by nitrogen sorption isotherms, X-ray diffraction (XRD), UV-vis diffuse reflectance spectra (UV-vis DRS), X-ray photoelectron spectra (XPS), Fourier transform infrared spectroscopy (FTIR), H-2 temperature-programmed reduction (H-2-TPR) and NH3 temperature-programmed desorption (NH3-TPD) techniques. It was realized that iron oxide mainly existed in the form of isolated Fe3+ in an oxidic environment. Fe/Al-Lap catalysts showed high catalytic activities in the temperature range of 120-200 degrees C without the presence of excessive O-2. This can be attributed to the interaction between iron oxide and alumina, which improve the redox property of Fe3+ efficiently. In addition, the strong acidity of catalysts and good dispersion of iron oxide were also beneficial to oxidation reaction. Among them, 7% Fe/Al-Lap catalyst presented the best catalytic performance at 180 degrees C. Finally, the catalytic and deactivation mechanisms were explored. Crown Copyright (C) 2013 Published by Elsevier B.V. All rights reserved.
Keywords:Alumina-intercalated clay;H2S selective oxidation;Sulfur yield;Sulfur selectivity;Catalyst deactivation