Promoted catalytic performance of Ag-Mn bimetal catalysts synthesized through reduction route

• Published in: Journal of environmental sciences (China) Vol. 137; pp. 358 - 369
• Main Authors: Hu, Wenkai, Guo, Tao, Ma, Kaiyao, Li, Xu, Luo, Wangting, Wu, Mingzhi, Guo, Hao, Zhang, Yaxin, Shangguan, Wenfeng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2024
• Subjects: Ag-Mn; Benzene oxidation; Catalytic performance; Reduction route; Ag-Mn; Reduction route; Benzene oxidation; Catalytic performance
• ISSN: 1001-0742; 1878-7320
• DOI: 10.1016/j.jes.2022.10.045

•The loading of silver greatly improved the physico-chemical properties and catalytic activity of manganese oxides.•Silver loaded using reduction method resulted in more active oxygen species.•The Ag-Mn bimetal catalysts synthesized via reduction method showed lower T90 of 203 °C than other samples. VOCs can exert great harm to both human and environment, and catalytic oxidation is believed to be an effective technique to eliminate these pollutants. In this paper, Ag-Mn bimetal catalysts with 10 wt.% of silver were synthesized using doping, impregnation, and reduction methods respectively, and then they were applied to the catalytic oxidation of benzene. Through series of characterizations it showed that the loading of silver using reduction method significantly resulted in improved physico-chemical properties of manganese oxides, such as larger surface area and pore volume, higher proportion of surface Mn3+ and Mn4+, stronger reducibility and more active of surface oxygen species, which were all beneficial to its catalytic activity. As a result, the Ag-Mn catalysts synthesized by reduction method showed a lower T90 value (equals to the temperature at which 90% of initial benzene was removed) of 203°C. Besides, both the used and fresh Ag-Mn catalysts synthesized by reduction method showed preferable stability in this research. The Ag-Mn bimetal catalyst synthesized through reduction method exerted largest specific surface area, pore volume, and surface lattice oxygen than other samples. Moreover, it also exhibited highest AOS value, stronger reducibility among all the as-prepared catalysts. As a result, the Ag-Mn bimetal catalyst gained via reduction route showed lowest T90 value than other catalysts. [Display omitted]