Catalytic Oxidation and Adsorption of Elemental Mercury over CuCl2-Impregnated Sorbents

CuCl2-impregnated sorbents were employed to remove elemental mercury from flue gas. Three carriers including neutral Al2O3, artificial zeolite, and activated carbon have been investigated in this research. The performances of these prepared sorbents have been tested in a bench-scale fixed-bed reactor under different simulated flue gas atmospheres and temperatures (333-573 K). CuCl2-impregnated activated carbon showed the best adsorption ability. However, CuCl2-impregnated neutral Al2O3 and zeolite have demonstrated an adsorption rate similar to that of CuCl2-impregnated activated carbon in the early stage of the tests (5 min), and they achieved relatively high mercury oxidation efficiencies. These non-carbon sorbents could remarkably enhance the technoeconomical properties of mercury removal in coal-fired power plants and have great potentials in industrial application. The appropriate mercury capture temperature for these sorbents is 333-473 K. The possible mechanisms of elemental mercury oxidation have been discussed.