Influence of flue gas components on the mercury adsorption/oxidation by mechanochemical S2Cl2-modified sawdust coke

The effects of flue gas components (O-2, CO2, SO2 and NO) on the Hg-0 removal of mechanochemical S2Cl2-modified BC (S2Cl2-MC) were explored based on the Hg-0 removal efficiency/amount, Hg-0 adsorption amount and Hg2+ escape amount/ratio. The BET, FTIR, XPS, and Hg-TPD were used to obtain relevant physicochemical properties. It shows O-2 and CO2 promote the Hg2+ escape but inhibit Hg-0 adsorption. O-2 slightly affects Hg-0 removal, while CO2 promotes it. 400 similar to 800 ppm SO2 slightly affect Hg-0 removal, while 1200 ppm SO2 facilitates Hg2+ escape and Hg0 adsorption. SO2 affects Hg2+ escape ratio little. As NO concentration increases, the Hg2+ escape is promoted while Hg-0 adsorption is inhibited. O-2 and CO2 do not change the mercury forms. SO2 and NO promote the production of HgSO4 and Hg(NO3)(2), respectively. The Hg-0 adsorption might mainly depend on the physical properties of adsorbents.

Automated summary

This study investigated the effects of flue gas components (O2, CO2, SO2, and NO) on the Hg-0 removal of mechanochemical S2Cl2-modified BC (S2Cl2-MC). It was found that O2 and CO2 promoted the escape of Hg2+ but inhibited the adsorption of Hg-0, while SO2 and NO had a certain promoting effect on the removal of Hg-0.