A series of Sm-Mn mixed oxide catalysts were prepared via precipitation using various precipitants,namely Na_(2)CO_(3)(NH_(4))_(2)CO_(3),and NH_(3)·H_(2)O,and evaluated for the selective catalytic reduction(SCR)o...A series of Sm-Mn mixed oxide catalysts were prepared via precipitation using various precipitants,namely Na_(2)CO_(3)(NH_(4))_(2)CO_(3),and NH_(3)·H_(2)O,and evaluated for the selective catalytic reduction(SCR)of NO_(x)with NH_(3)at low temperatures.Various characterisation techniques were used to determine the physicochemical properties of the catalysts,and it is found that their catalytic performance is greatly influenced by the nature of the precipitation agent used.It is found that Sm_(0.1)Mn-Na_(2)CO_(3)and Sm_(0.1)Mn-(NH_(4))_(2)CO_(3)exhibit superior catalytic performance in the SCR reaction to that of Sm_(0.1)Mn-NH_(3)·H_(2)O due to an abundance of surface acid sites,high surface concentration of Mn^(4+),and high NO oxidation capacity.From in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFT)analysis,we conclude that the Sm-Mn catalysts follow both Eley-Rideal and Langmuir-Hinshelwood mechanisms,and that the Eley-Rideal mechanism is dominant at elevated temperatures.展开更多
基金Project supported by the National Key Research and Development Program of China(2016YFC0204300)the National Natural Science Foundation of China(21577034,21922602,22076047,U1905214)+2 种基金Shanghai Risingstar Program(20QB1400400)Shanghai Science and Technology Innovation Action Plan(20dz1204200)Fundamental Research Funds for the Central Universities。
文摘A series of Sm-Mn mixed oxide catalysts were prepared via precipitation using various precipitants,namely Na_(2)CO_(3)(NH_(4))_(2)CO_(3),and NH_(3)·H_(2)O,and evaluated for the selective catalytic reduction(SCR)of NO_(x)with NH_(3)at low temperatures.Various characterisation techniques were used to determine the physicochemical properties of the catalysts,and it is found that their catalytic performance is greatly influenced by the nature of the precipitation agent used.It is found that Sm_(0.1)Mn-Na_(2)CO_(3)and Sm_(0.1)Mn-(NH_(4))_(2)CO_(3)exhibit superior catalytic performance in the SCR reaction to that of Sm_(0.1)Mn-NH_(3)·H_(2)O due to an abundance of surface acid sites,high surface concentration of Mn^(4+),and high NO oxidation capacity.From in situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFT)analysis,we conclude that the Sm-Mn catalysts follow both Eley-Rideal and Langmuir-Hinshelwood mechanisms,and that the Eley-Rideal mechanism is dominant at elevated temperatures.
