Mercury removal from flue gas by magnetic iron-copper oxide modified porous char derived from biomass materials

In this work, a magnetic iron-copper oxide modified porous char derived from biomass materials was prepared by microwave activation and ultrasonic-assisted impregnation method to remove Hg-0 from flue gas. The effects of operating parameters and flue gas components on Hg-0 removal performance as well as physicochemical properties of samples were studied. The reaction mechanism and the regeneration performance of samples were also investigated. The experimental results display that the biomass-based porous char derived from microwave and steam activation exhibits a larger pore volume, higher surface area and well-developed pore structure. The ultrasonic treatment promotes the dispersion of active components on the surface of samples. The CuFe0.3/WSWU10(500) sample exhibits good Hg-0 removal performance, and about 90.58% of Hg-0 is captured from flue gas at 130 degrees C. Increasing SO2 concentration inhibits Hg(0 )removal. The presence of O-2 and NO promotes the removal of Hg-0. Low concentration of water vapor ( > 4%) improves Hg-0 removal performance, while excessive water vapor plays an opposite role. The presence of copper/iron active components, chemisorbed oxygen and lattice oxygen over the surface of adsorbent is conducive to the removal of Hg-0. The modified sample exhibits a good regeneration performance.