Catalytic performance and reaction mechanism of an iron-loaded catalyst derived from blast furnace slag for the CO-SO2 reaction to produce sulfur

For realizing resource desulfurization and high-value sulfur recovery, an iron-loaded catalyst was prepared from steelmaking byproduct blast furnace slag to reduce SO2 to elemental sulfur with CO. SO2 conversion efficiency, sulfur selectivity, and sulfur yield were used to evaluate the catalyst behavior. The catalyst with 15wt.% Fe2O3 at 500 degrees C showed the best activity performance. The changes in the structure and active phase of the catalyst as well as the complete reaction pathway were explored. A series of in situ diffuse reflectance infrared Fourier transform spectroscopy experiments were used to study the adsorption and desorption processes of CO and SO2, and a large number of sulfates were formed on the catalyst surface after the reaction. Combined with the experimental performance, the strong adsorption of BFS and the production pathway of H2S were proposed. The prepared iron-loaded catalysts followed the redox mechanism and the COS intermediate mechanism in the reaction.