Fabrication, Characterization And Properties Of Rare Earth Oxide Desulfurizer For Hot Coal Gas

Pure metal oxides are used as desulfurizer to remove H2S from hot gases easily suffered from evaporation, loss in the surface area and porosity, sintering and mechanical disintegration that affect their performance and life time adversely. In order to overcome these problems rare earth metal oxides were loaded on inert materials. In this study, La(Sm)MeOx/MCM-41 desulfurizers were prepared by means of sol-gel method. For comparison, we also synthesized pure rare earth metal oxides in same way. The H2S removal characteristics of the desulfurizer were investigated fixed-bed quartz reactor. By examining the effect of the reaction temperature, supports and gas composition on the desulfurization, we found that La(Sm)FeO₃/MCM-41 presented better performance than other desulfurizers for hot gas desulfurization under the conditions of T=500℃, WHSV=9000 ml/h·g, gas composition: H₂-10.5%, H₂S-0.33%, CO-17.1%, N₂ balance gas.The properties of desulfurizers before and after the reaction were characterized using techniques such as, X-ray diffraction (XRD), X-ray photoelectron spectra (XPS), transmission electron microscopy (TEM), thermogravimetry analysis (TGA), BET specific surface area, temperature-programmed desorption (CO₂-TPD) and temperature-programmed reduction (H2-TPR).