Structure-activity relationships, product species distribution and the mechanism of effect of multi-component flue gas on Hg 0 adsorption and oxidation over CuO/ACs.

A series of Cu-doped activated cokes (CuO/ACs) were synthesized via an impregnation method and applied for the removal of elemental mercury (Hg 0 ). Structure-activity relationships between Hg 0 removal and CuO/AC surface characteristics were identified. Hg 0 removal over CuO/AC occurs through a combination of physisorption and chemisorption and is mainly dominated by chemisorption. It was found that 1 nm micropores facilitate Hg 0 physisorption. Hg 0 could weakly adsorb onto an O-terminated crystal layer, whereas strongly adsorb onto Cu-terminated single highly dispersed, clustered and bulk CuO (110) crystal planes via the Mars-Maessen mechanism. Product distributions and mechanisms of Hg 0 adsorption and oxidation over the CuO/AC catalyst under multi-component flue gases are also discussed. O 2 enhances both physisorption and chemisorption toward Hg 0 by 38%. Inhibition of Hg 0 removal by SO 2 originates from the competitive adsorption and deactivation of CuO cation vacancies, whereas the impact is weakened by O 2 through generating 20% of physically adsorbed mercury product species. NO and O 2 promote Hg 0 chemisorption efficiency by 93% to form Hg(NO 3 ) 2 . HOCl and/or Cl 2 produced by HCl can oxidize 100% of Hg 0 to HgCl 2 , and the catalytic oxidation efficiency is approximately 29%, but O 2 slightly lowers the Hg 0 catalytic oxidation efficiency by 8%. The affinity ability between various flue gases and Hg 0 follows the order O 2 < NO < HCl.