title: Mechanisms and reaction pathways for simultaneous oxidation of NOx and SO₂ by ozone determined by in situ IR measurements.
abstract: Ozone (O3) oxidation combined with wet scrubbing is a promising method for the simultaneous removal of SO2 and NOx in flue gas. In this study, the O3 oxidation processes of NO and SO2, as well as their coexistence, were investigated using an in situ IR spectrometer. Experimental results showed that the O3 concentration and the reaction temperature played critical roles in the O3 oxidation process of NO. Around 80°C, when inlet molar ratio of O3/NO was less than 1, NO was mainly oxidized to NO2, while when the ratio was greater than 1, NO would be further oxidized to NO3, N2O5, and HNO3. NO3 was the key intermediate product for the formation of N2O5 and HNO3. However, the subsequent reactions of NO3 were temperature dependence. With the increase of reaction temperature above 100°C, the concentration of NO2 increased whereas the concentrations of N2O5 and HNO3 decreased. The oxidation of SO2 by O3 was negligible and SO2 had little influence on the oxidation of NO in the simultaneous oxidation of NO and SO2. Finally, based on the in situ IR results, the oxidation mechanism is discussed and the reaction pathways are proposed.
authors.affiliation: Department of Environment Engineering, Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Yuhangtang Road 866, Hangzhou 310058, PR China.
authors.forename: Chenglang
authors.initials: C
authors.lastname: Sun
authors.affiliation: Department of Environment Engineering, Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Yuhangtang Road 866, Hangzhou 310058, PR China.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhao
authors.affiliation: Department of Environment Engineering, Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Yuhangtang Road 866, Hangzhou 310058, PR China.
authors.forename: Zhuokai
authors.initials: Z
authors.lastname: Zhuang
authors.affiliation: Department of Environment Engineering, Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Yuhangtang Road 866, Hangzhou 310058, PR China. Electronic address: haiqiangwang@zju.edu.cn.
authors.forename: Haiqiang
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Environment Engineering, Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Yuhangtang Road 866, Hangzhou 310058, PR China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Environment Engineering, Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Yuhangtang Road 866, Hangzhou 310058, PR China.
authors.forename: Xiaole
authors.initials: X
authors.lastname: Weng
authors.affiliation: Department of Environment Engineering, Zhejiang University, Yuhangtang Road 866, Hangzhou 310058, PR China; Zhejiang Provincial Engineering Research Center of Industrial Boiler & Furnace Flue Gas Pollution Control, Yuhangtang Road 866, Hangzhou 310058, PR China. Electronic address: zbwu@zju.edu.cn.
authors.forename: Zhongbiao
authors.initials: Z
authors.lastname: Wu
mesh_terms: D000393:Air Pollutants / Q000737:chemistry*; D000397:Air Pollution / Q000517:prevention & control; D009589:Nitrogen Oxides / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry*; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013458:Sulfur Dioxide / Q000737:chemistry*
chemical_list: D000393:Air Pollutants; D009589:Nitrogen Oxides; D016877:Oxidants; D013458:Sulfur Dioxide; D010126:Ozone
keywords: In-situ IR spectra; Nitrogen oxides; Ozone injection; Reaction mechanism; Sulfur oxides