The surfactant adsorption behavior of fly ash doped with small amounts of activated carbon has been evaluated. The potential impact of activated carbon deposition on the fly ash utilization is significantly depending on the amount of activated carbon and the type. Preliminary results on carbon surface modification shows that the ozone treatment can decrease the surfactant adsorptivity of activated carbon, either within or without fly ash, thus minimizing the impact of activated carbon on the fly ash utilization for concrete. Two wet oxidation methods were also employed to modify the surface of FGD activated carbons. In all cases the equilibrium Hg~0 adsorption capacity of oxidized activated carbons measured in a fixed bed reactor is less than that of the virgin sample. The destruction of the binding sites for oxidized mercury species on carbon surface is a possible explanation for this trend. The results suggest that oxidative treatment of commercial activated carbon can produce sorbents with minimal impact on fly ash utilization, while maintaining an acceptable, though lower mercury adsorption capacity. Overall, activated carbon surfaced oxidation deserves further examination as a simple route to develop ash-utilization-friendly sorbents for gas phase mercury emission control in utility boilers.
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