Outstanding Performance of Recyclable Amorphous MoS3 Supported on TiO2 for Capturing High Concentrations of Gaseous Elemental Mercury: Mechanism, Kinetics, and Application

Hg 0 capture by sorbents was a promising technology to control Hg 0 emission from coal-fired power plants and smelters. However, the design of a high performance sorbent and the predicting of the extent of Hg 0 adsorption were both extremely limited due to the lack of adsorption kinetics and structure–activity relationship. In this work, the adsorption kinetics of gaseous Hg 0 onto MoS 3 /TiO 2 was investigated and kinetic parameters were obtained by fitting breakthrough curves. According to the kinetic parameters, the removal efficiency, the adsorption rate and the capacity for Hg 0 capture were accurately predicted. Meanwhile, the structure–activity relationship of metal sulfides for gaseous Hg 0 adsorption was built. The chemical adsorption rate of gaseous Hg 0 was found to mainly depend on the amount of surface adsorption sites available for the physical adsorption of Hg 0, the amount of surface S 2 2– available for Hg 0 oxidation and gaseous Hg 0 concentration. As MoS 3 /TiO 2 showed a superior performance for capturing high concentrations of Hg 0 due to the large number of surface adsorption sites for the physical adsorption of gaseous Hg 0, it has promising applications in recovering Hg 0 from smelting flue gas.