Simultaneous removal of mercury and 1,2-dichlorobenzene from flue gas by Ru-based catalyst

Abstract

To solve the pollution problem of mercury and dioxin emission, the catalytic oxidation techniques were introduced, and Ru-based catalyst manifested an excellent performance for simultaneously removing elemental mercury (Hg0) and 1,2-dichlorobenzene (o-DCB) in flue gas. Ce-Zr-Ru presented the highest removal efficiency for o-DCB, which could reach more than 90% above 325 ℃. Besides, it had a good chemical stability, and the o-DCB removal efficiency maintained above 90% after 12 h and 5 cycles. The existence of o-DCB was beneficial for Hg0 removal, and the Hg0 catalytic efficiency of Ce-Zr-Ru can reach nearly 100% at a wide temperature window of 200–400 ℃ in the presence of o-DCB. O2 play a critical role on the catalytic reaction process, which can be activated to oxidize Hg0 and o-DCB. Moreover, the generated hydrogen chloride and chlorine species by catalyzing o-DCB would react Hg0 and HgO to form HgCl2, which can be desorbed from the surface of the catalysts and entered to flue gas.