Mossbauer Study on the High Temperature Desulfurization of Fuel Gas——The Mechanisms of Desulfurization,Deactivation, and Regeneration of Ferric Oxide Sorbent

The ⁵⁷Fe Mossbauer spectroscopy was used to investigate the transformations of ferric oxide sorbent during hot fuel gas desulfurizahon. The results show that the high dispcrsive elemental iron phase formed rapidly from the reduction of fcrric oxide becomes the active dcsulfurisation phase. The sulfided product of the sorbent is the troilitc FoS. The carbonisation process progresses in parallel with the dcsulfurization process. The formation of bulk carbide θ-Fe₃C results directly in the loss of sulfur capacity, and the depositing of surface carbon cventllally leads the surfent to the deactivation. The initial desulfurization activity of the deactivated sorbent can be efficiently regained by a controlled oxidation regeneration treatment with an air / steam mixture around 973K.