title: Mercury oxidation and adsorption characteristics of potassium permanganate modified lignite semi-coke.
abstract: The adsorption characteristics of virgin and potassium permanganate modified lignite semi-coke (SC) for gaseous Hg0 were investigated in an attempt to produce more effective and lower price adsorbents for the control of elemental mercury emission. Brunauer-Emmett-Teller (BET) measurements, X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) were used to analyze the surface physical and chemical properties of SC, Mn-SC and Mn-H-SC before and after mercury adsorption. The results indicated that potassium permanganate modification had significant influence on the properties of semi-coke, such as the specific surface area, pore structure and surface chemical functional groups. The mercury adsorption efficiency of modified semi-coke was lower than that of SC at low temperature, but much higher at high temperature. Amorphous Mn7+, Mn6+ and Mn4+ on the surface of Mn-SC and Mn-H-SC were the active sites for oxidation and adsorption of gaseous Hg0, which oxidized the elemental mercury into Hg2+ and captured it. Thermal treatment reduced the average oxidation degree of Mn(x+) on the surface of Mn-SC from 3.80 to 3.46. However, due to the formation of amorphous MnOx, the surface oxidation active sites for gaseous Hg0 increased, which gave Mn-H-SC higher mercury adsorption efficiency than that of Mn-SC at high temperature.
authors.affiliation: College of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao 266590, China. sdkdzhw@163.com
authors.forename: Huawei
authors.initials: H
authors.lastname: Zhang
authors.forename: Jitao
authors.initials: J
authors.lastname: Chen
authors.forename: Peng
authors.initials: P
authors.lastname: Liang
authors.forename: Li
authors.initials: L
authors.lastname: Wang
mesh_terms: D000327:Adsorption; D003031:Coal / Q000032:analysis*; D008628:Mercury / Q000737:chemistry* / Q000302:isolation & purification; D056951:Photoelectron Spectroscopy; D011196:Potassium Permanganate / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D003031:Coal; D011196:Potassium Permanganate; D008628:Mercury