Insight into the Mercury Removal Mechanism of Copper Salt-Modified Biomass Coke in an Oxyfuel Combustion Atmosphere

The development of effective sorbents using biomass isimportantto achieve mercury removal in coal combustion flue gas. In this work,a biomass sorbent was prepared by using rice husk as a raw materialand CuCl2 solution as a modifier. The experiment exploredthe mercury removal ability of rice husk with different modificationsolution concentrations. The sorbent showed the best mercury removalcapacity with 0.15 mol/L CuCl2 solution modified rice huskcoke at an inlet mercury concentration of 54.4 mu g/m(3) at 150 degrees C. It was found that the modification made CuCl2 adhere to the surface of the coke sample successfully andchlorine-containing functional groups and copper-containing functionalgroups in the coke sample both promoted the adsorption of mercury.The increase in chemisorbed oxygen due to the modification also promotedthe sorbent removal of mercury. The increase of adsorption temperatureand inlet mercury concentration was beneficial to mercury removal,but too high temperature had a negative effect on its mercury removal.The purpose of this work is to explore a novel approach for the efficientuse of this agricultural waste, apply it to mercury removal in oxyfuelcoal-fired power plants, and provide technical support and theoreticalguidance for its application in industry.