Photocatalytic oxidation removal of Hg0 by ternary Ag@AgCl/Ag2CO3 hybrid under fluorescent light

Photocatalytic oxidation removal of elemental mercury (Hg-0) by Ag@AgCl/Ag2CO3 hybrids was carried out in a wet scrubbing reactor under fluorescent light. The photocatalysts synthesized via a modified coprecipitation method were characterized by using SEM-EDS, HRTEM, N-2 adsorption-desorption, XRD, XPS, DRS, and ESR. Effects of operational parameters on Hg-0 removal, including AgCl content, fluorescent light (FSL) irradiation, pH value, reaction temperature, and flue gas components (O-2, SO2 and NO) were studied in detail. Furthermore, simultaneous removal of Hg-0 and SO2 was investigated and the possible mechanism of highly enhanced Hg-0 removal efficiency was proposed. The results showed that AgCI amount, fluorescent light irradiation, reaction temperature, SO2 and NO had notable impact on Hg-0 removal efficiency. Simultaneous removal efficiencies of 98% for SO2 and 80% for Hg-0 were obtained by coupling Ag@AgCl(0.3)/Ag2CO3 with Ca(OH)(2) under FSL The trapping studies of reactive radicals exhibited that holes (h(+)) were one of the main reactive species for Hg-0 removal. (C) 2017 Elsevier B.V. All rights reserved.