Combined removal with other coal fired pollutants was an effective method to control mercury emission during coal combustion.Accelerating the transformation of Hg0 to Hg2+ could enhance the performance of air pollution control devices in mercury emission control.Therefore

it is necessary to understand the influence factors of mercury speciation transformation.A bench scale test rig was built to simulate the process of mercury oxidation by gas components by using the Ontario Hydro Method for mercury detection at medium-to-low temperature.It was found that 90% Hg0 could be oxidized by Cl2 at the concentration of 10 μl8226;L-1.The process of Hg0 oxidation was sensitive within a range of SO2 concentration

out of which SO2 concentration had little influence on Hg0 oxidation.HCl

as the reaction product of H2O and Cl2

could also oxidize mercury from Hg0 to Hg2+

but its oxidation ability was weaker than Cl2

which generally made H2O an inhibitor of Hg0 oxidation.The process of NO2 decomposition would release free oxygen atoms which could oxidize mercury from Hg0 to Hg2+

so mercury oxidation by NO2 should be considered in a comprehensive kinetics model.