title: Catalytic oxidation of Hg(0) by MnOx-CeO2/γ-Al2O3 catalyst at low temperatures.
abstract: MnOx-CeO2/γ-Al2O3 (MnCe) selective catalytic reduction (SCR) catalysts prepared by sol-gel method were employed for low-temperature Hg(0) oxidation on a fixed-bed experimental setup. BET, XRD and XPS were used to characterize the catalysts. MnCe catalysts exhibited high Hg(0) oxidation activity at low temperatures (100-250 °C) under the simulated flue gas (O2, CO2, NO, SO2, HCl, H2O and balanced with N2). Only a small decrease in mercury oxidation was observed in the presence of 1200 ppm SO2, which proved that the addition of Ce helped resist SO2 poisoning. An enhancing effect of NO was observed due to the formation of multi-activity NOx species. The presence of HCl alone had excellent Hg(0) oxidation ability, while 10 ppm HCl plus 5% O2 further increased Hg(0) oxidation efficiency to 100%. Hg(0) oxidation on the MnCe catalyst surface followed the Langmiur-Hinshelwood mechanism, where reactions took place between the adsorbed active species and adsorbed Hg(0) to form Hg(2+). NH3 competed with Hg(0) for active sites on the catalyst surface, hence inhibiting Hg(0) oxidation. This study shows the feasibility of a single-step process integrating low-temperature SCR and Hg(0) oxidation from the coal combustion flue gas.
authors: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
authors: Pengying
authors: P
authors: Wang
authors: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China. Electronic address: susheng_sklcc@hotmail.com.
authors: Sheng
authors: S
authors: Su
authors: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China. Electronic address: xiangjun@mail.hust.edu.cn.
authors: Jun
authors: J
authors: Xiang
authors: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
authors: Huawei
authors: H
authors: You
authors: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
authors: Fan
authors: F
authors: Cao
authors: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
authors: Lushi
authors: L
authors: Sun
authors: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
authors: Song
authors: S
authors: Hu
authors: State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074, PR China.
authors: Yun
authors: Y
authors: Zhang
mesh_terms: D000327:Adsorption; D000393:Air Pollutants / Q000737:chemistry*; D002384:Catalysis; D003031:Coal; D005740:Gases / Q000737:chemistry; D006851:Hydrochloric Acid / Q000737:chemistry; D008628:Mercury / Q000737:chemistry*; D010084:Oxidation-Reduction; D010087:Oxides / Q000737:chemistry*; D013696:Temperature
chemical_list: D000393:Air Pollutants; D003031:Coal; D005740:Gases; D010087:Oxides; D008628:Mercury; D006851:Hydrochloric Acid
keywords: Cerium oxide; Manganese oxide; Mercury; SCR