LAUSR

This work is to systematically study the mercury-removal behavior of activated coke (AC), regeneration of spent AC by microwave treatment and subsequent recycling of Hg0. The powdery (AC) was obtained under coal-fired hot gas conditions in a drop-tube reactor. The adsorption mechanism and capacity of the AC for Hg0 removal in a H2O + SO2 + O2 atmosphere were investigated. The regeneration of the AC by microwave heating and recovery of Hg0 were studied. The results showed that this AC preparation method can greatly simplify the process, and the AC's large surface area, developed pore structure, and abundant functional groups played a key role in the adsorption of Hg0. The adsorption mechanism and the optimum reaction conditions were determined, with a highest average Hg0-adsorption efficiency of 91% obtained at 70 °C in 3 h. Desorption of Hg0 was also studied, in which the alkaline-functional-group content and pore structure were enhanced, and S was detected by X-ray photoelectron spectroscopy in microwave-regenerated AC, which could improve the Hg0 removal efficiency increased to 96% after five adsorption/desorption cycles. The Hg0 could subsequently be recovered from the desorbed gas by condensation with an efficiency of 87.4% using ice-water.