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Wang J, Liu W, Hu Y, Song L, Hu Y, Hou Y, Hu W. Optimizing low-temperature CO oxidation under realistic combustion conditions: The impact of CeO 2 morphology on Au/CeO 2 catalysts. JOURNAL OF HAZARDOUS MATERIALS 2025; 487:137182. [PMID: 39813932 DOI: 10.1016/j.jhazmat.2025.137182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2024] [Revised: 12/29/2024] [Accepted: 01/09/2025] [Indexed: 01/18/2025]
Abstract
The development of carbon monoxide oxidation catalysts for complex gas environments faces significant challenges in fire scenarios. Only a few representative gases are used as interfering components in simulated real smoke under laboratory conditions, which cannot accurately reflect the performance of catalysts in a real fire. Herein, Au/CeO2 catalysts with high activity were prepared by adjusting the morphology (rod, cube, polyhedron and irregular particles) and exposed crystal surface ratio of CeO2. Rod-like Au/CeO2 (Au/CeO2-NR) achieved 99 % CO conversion at 25 °C and demonstrated excellent water resistance. This excellent activity originates from the high oxygen vacancy concentration of the CeO2-NR and the interaction between Au species and the carrier. A testbed was established by connecting a steady-state tube furnace with a catalytic fixed-bed reactor to evaluate the CO elimination performance of the catalyst under realistic combustion conditions. Despite competitive adsorption of small molecules (H2O, acetone, etc.) on the active sites, Au/CeO2-NR eliminates carbon monoxide in real combustion atmospheres at only 60 °C. This study provides a method for evaluating the catalytic activity of CO in realistic environments, which is promising for practical use in application scenarios dealing with toxic fumes.
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Affiliation(s)
- Jing Wang
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, PR China
| | - Wei Liu
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, PR China
| | - Yandong Hu
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, PR China
| | - Lei Song
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, PR China
| | - Yuan Hu
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, PR China; Suzhou Key Laboratory for Urban Public Safety, Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, Jiangsu 215123, PR China
| | - Yanbei Hou
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, PR China; Suzhou Key Laboratory for Urban Public Safety, Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, Jiangsu 215123, PR China
| | - Weizhao Hu
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230026, PR China; Suzhou Key Laboratory for Urban Public Safety, Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, Jiangsu 215123, PR China.
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Liu W, Zhou Y, Wang J, Hu Y, Hu W. Enhancing low-temperature CO removal in complex flue gases: A study on La and Cu doped Co 3O 4 catalysts under real-world combustion environment. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134174. [PMID: 38574661 DOI: 10.1016/j.jhazmat.2024.134174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 03/22/2024] [Accepted: 03/29/2024] [Indexed: 04/06/2024]
Abstract
Designing CO oxidation catalysts for complex flue gases conditions is particularly challenging in fire scenarios. Traditional flue gas simulations use a few representative gases but often fail to adequately evaluate catalyst performance in real-world combustion conditions. In this study, we developed doping strategies using La and Cu to enhance the water resistance of Co3O4 catalysts. Catalyst 0.1La-Co3O4-CuO/CeO2 exhibits exceptional low-temperature catalytic activity, achieving 100% conversion at 130 °C. This enhancement is largely due to the introduction of La, which increases the active Co3+/Co2+ ratio and suppresses hydroxyl group formation on the Co3O4 surface. Cu doping also changes the Co3O4 lattice structure, forming Cu+ as active sites and enhancing the activity at low temperatures. For the first time, steady-state tube furnace and fixed bed were employed to evaluate the catalytic performance of CO in actual combustion atmosphere. Catalyst 0.1La-Co3O4-CuO/CeO2 maintains excellent catalytic efficiency (T100 = 120 °C) under well-ventilated conditions. However, its activity significantly decreases in poorly ventilated environments, due to the competitive adsorption of small molecules at active sites, such as acetone, commonly found in smoke. This study provides valuable insights for designing water-resistant, low-temperature, non-noble metal catalysts and offers a methodology for evaluating CO catalytic activity in real-world environments.
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Affiliation(s)
- Wei Liu
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China
| | - Yifan Zhou
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China
| | - Jing Wang
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China
| | - Yuan Hu
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China
| | - Weizhao Hu
- State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, PR China.
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