Preparation of Manganese Blending-Modified Activated Coke for Flue Gas Desulfurization

In this study, the preparation and desulfurization application of MnO₂ and pyrolusite blending-modified activated cokes (ACM and ACP) were studied. Thermodynamic calculation shows that the blended metal oxides could be reacted with the solid carbon and gaseous products H₂, CO, and CO₂ for activation. The physicochemical properties of the blending-modified ACP and ACM responded considerably differently to preparation conditions. The blended metal oxide significantly improved the mesoporous structure of the modified activated cokes, as well as the surface acidic and basic functional groups. Different metal oxides played different roles in the pore structure and surface functional group evolution, and the current investigation indicates that MnO₂ is more favorable than pyrolusite. The enhanced acidic and basic functional groups, coupled with the catalysis of metal oxides, improved the desulfurization performance of the modified activated cokes. The sulfur capacities of the prepared ACP and ACM were 47.9-208.9 and 119.4-205.9 mg/g, respectively, which were much greater than the sulfur capacity of the fresh activated coke.