Cu‐modified Fe‐Mn magnetic mercury adsorbent and anti‐SO₂ characteristic

A series of Fe 6 Mn 1 Cu x adsorbents for mercury removal were prepared by using co‐precipitation and impregnation methods. The performance of mercury adsorption and anti‐SO 2 characteristic was studied in a fixed‐bed experimental system. The effect of Cu doping amount, reaction temperature, and flue gas components on mercury removal was investigated. The mercury species on the spent adsorbent was analyzed through Hg‐TPD test. The physical–chemical features were characterized by using the N 2 adsorption/desorption, VSM, XPS, and XRD. It was found that the Fe 6 Mn 1 Cu 0.4 exhibited a high performance of mercury adsorption and well magnetic property and good sulfur resistance. Under high concentration of SO 2 , the average adsorption efficiency of Fe 6 Mn 1 Cu 0.4 adsorbent achieved 99%. Cu modification optimized the pore structure and improved the mercury removal performance as well as SO 2 resistance. The XPS analysis indicated that Mn 4+ was the main form that played an important role in oxidizing Hg 0 , as a result of decrement of Mn 4+ after mercury adsorption. Mercury adsorbed on the spent adsorbent was HgO and HgSO 4 .