title: The use of vacuum ultraviolet irradiation to oxidize SO₂ and NOx for simultaneous desulfurization and denitrification.
abstract: A simple and efficient method for simultaneous desulfurization and denitrification via vacuum ultraviolet (VUV) irradiation and with no additional chemicals is presented. The simultaneous removal of 90% SO2 and 96% NOx (NO+NO2) was achieved from the simulated flue gas under the irradiation from a low-pressure mercury lamp with main wavelengths of 185 and 254 nm, respectively. The composition, flow rate, and temperature of the simulated flue gas, as well as the VUV light intensity, were evaluated as the factors impacting on the efficiency of SO2 and NOx removal. The OH, HO2, O, and O3 produced from the photolysis of H2O and O2 were concluded as the major reactive oxygen species that oxidized SO2 and NOx. The additional OH and HO2 generated through the reactions of NO+HO2 and SO2+OH/HO2 improved treatment efficiency, while the oxidation products of NOx, e.g., NO2, HNO2, HNO3, and HNO4, consumed massive reactive oxygen species (such as O, OH, and HO2) and thereby reducing the removal efficiencies. The main reaction products were characterized as H2SO4 and HNO3 by ion chromatography, which could be used as chemical or fertilizer raw materials.
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China.
authors.forename: Junhui
authors.initials: J
authors.lastname: Ye
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China. Electronic address: shangjing@pku.edu.cn.
authors.forename: Jing
authors.initials: J
authors.lastname: Shang
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China.
authors.forename: Weiwei
authors.initials: W
authors.lastname: Xu
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China.
authors.forename: Jia
authors.initials: J
authors.lastname: Liu
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Feng
authors.affiliation: State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, People's Republic of China. Electronic address: tzhu@pku.edu.cn.
authors.forename: Tong
authors.initials: T
authors.lastname: Zhu
mesh_terms: D000393:Air Pollutants / Q000737:chemistry / Q000528:radiation effects*; D000397:Air Pollution / Q000517:prevention & control*; D017942:Nitric Acid / Q000737:chemistry; D009589:Nitrogen Oxides / Q000737:chemistry / Q000528:radiation effects*; D010084:Oxidation-Reduction; D017382:Reactive Oxygen Species / Q000737:chemistry; D013458:Sulfur Dioxide / Q000737:chemistry / Q000528:radiation effects*; D013464:Sulfuric Acids / Q000737:chemistry; D014466:Ultraviolet Rays; D014618:Vacuum
chemical_list: D000393:Air Pollutants; D009589:Nitrogen Oxides; D017382:Reactive Oxygen Species; D013464:Sulfuric Acids; D013458:Sulfur Dioxide; D017942:Nitric Acid; C033158:sulfuric acid
keywords: Denitrification; Desulfurization; Flue gas treatment; Reactive oxygen species; VUV