Title: | Supported ceria-modified silver catalysts with high activity and stability for toluene removal |
Author(s): | Zhang Y; Liu Y; Xie S; Huang H; Guo G; Dai H; Deng J; |
Address: | "Key Laboratory of Beijing on Regional Air Pollution Control, Beijing Key Laboratory for Green Catalysis and Separation, MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China. School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China. Key Laboratory of Beijing on Regional Air Pollution Control, Beijing Key Laboratory for Green Catalysis and Separation, MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation, Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China. Electronic address: jgdeng@bjut.edu.cn" |
DOI: | 10.1016/j.envint.2019.04.062 |
ISSN/ISBN: | 1873-6750 (Electronic) 0160-4120 (Linking) |
Abstract: | "Herein we fabricated the supported single-atom silver catalysts using an in situ molten salt method. The Mn(2)O(3) nanowires supported single-atom silver catalyst (i.e., 0.06?ª+wt% Ag/Mn(2)O(3)) exhibited excellent catalytic activity for toluene combustion, with the temperatures required for 50 and 90% of toluene conversions being 170 and 205?ª+ degrees C, respectively, at a space velocity of 40,000?ª+mL/(g?ª+h). However, the toluene conversion at 205?ª+ degrees C quickly decreased from 90 to 30% within 2.5?ª+h of on-stream reaction. Based on the various characterization results, we found that there were no aggregation of Ag particles, no change in crystal structure of the Mn(2)O(3) nanowire support, and no carbon deposition on the catalyst surface, and the quick deactivation of 0.06?ª+wt% Ag/Mn(2)O(3) was mainly associated with the low oxygen activation ability. The proper CeO(2) addition to the 0.06?ª+wt% Ag/Mn(2)O(3) catalyst was found to not only improve the catalytic activity but also significantly enhance the stability of the catalyst. Toluene conversion at 195?ª+ degrees C over 0.63?ª+wt% CeO(2)-0.06?ª+wt% Ag/Mn(2)O(3) decreased by only 10% in 50?ª+h of on-stream reaction. Because Ag and CeO(2) particles were highly dispersed on the Mn(2)O(3) nanowire support, the oxygen species formed at the surface oxygen vacancies of CeO(2) could efficiently migrate to the active sites (i.e., the interface of Ag-Mn(2)O(3)) and replenish the surface reactive lattice oxygen species. Thus, the present single-atom silver catalyst is an alternative for commercial noble metal catalysts for the removal of VOCs" |
Keywords: | Air Pollutants/*analysis Air Pollution/analysis/*prevention & control Cerium/*chemistry China Environmental Restoration and Remediation/instrumentation/*methods Manganese/analysis Nanowires/*analysis Oxides/analysis Silver/*chemistry Toluene/*analysis Cat; |
Notes: | "MedlineZhang, Yang Liu, Yuxi Xie, Shaohua Huang, Haibao Guo, Guangsheng Dai, Hongxing Deng, Jiguang eng Research Support, Non-U.S. Gov't Netherlands 2019/05/12 Environ Int. 2019 Jul; 128:335-342. doi: 10.1016/j.envint.2019.04.062. Epub 2019 May 8" |