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Chen Y, Chen L, Liao Y, Chen Z, Ma X. Copper/Nickel/Cobalt modified molybdenum-tungsten-titanium dioxide-based catalysts for multi-pollution control of nitrogen oxide, benzene, and toluene: Enhanced redox capacity and mechanism study. J Colloid Interface Sci 2024; 659:299-311. [PMID: 38176239 DOI: 10.1016/j.jcis.2023.12.150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 12/19/2023] [Accepted: 12/26/2023] [Indexed: 01/06/2024]
Abstract
Previous studies have indicated the potential of monometallic-modified TiO2 catalysts in controlling nitrogen oxide (NOx) and volatile organic compounds (VOCs) in coal-fired flue gas. Unfortunately, increasing selective catalytic reduction (SCR) activity under complicated coal-fired flue gas status is tricky. In this study, modified Co-MoWTiO2 catalysts with multiple active sites were synthesized using the wet impregnation method, which exhibited excellent multi-pollution control ability of NO, benzene and toluene under low oxygen and high SO2 concentrations. The modification of Mo and Co achieved high dispersion and electron transfer. The interaction between W5+/W6+ and Co2+/Co3+ promoted gas-phase O2 adsorption on the catalyst surface, forming of reactive oxygen species (Oα). Density functional theory (DFT) calculations informed that the doping of Co effectively enhanced the NH3 and O2 adsorption capacity of the catalyst, and Co possessed the maximum adsorption energy for NH3 and O2. Possible pathways of multi-pollution control of NO, C6H6, and C7H8 were speculated. NH3/NH4+ on the Lewis/Bronsted acid site is reacted with intermediates of NO (e.g., NO2, nitrite, nitrate) via the Langmuir-Hinshelwood and Eley-Rideal mechanism. The introduction of NO and NH3 did not disrupt the oxidation pathways of benzene and toluene. Following the Mars-van Krevelen mechanism, C6H6 and C7H8 were progressively mineralized by Oα into CO2 and H2O.
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Affiliation(s)
- Yin Chen
- Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization, School of Electric Power, South China University of Technology, Guangdong, Guangzhou 510640, China
| | - Lin Chen
- College of Information and Mechanical & Electrical Engineering, Ningde Normal University, Fujian, Ningde 352100, China
| | - Yanfen Liao
- Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization, School of Electric Power, South China University of Technology, Guangdong, Guangzhou 510640, China.
| | - Zhuofan Chen
- Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization, School of Electric Power, South China University of Technology, Guangdong, Guangzhou 510640, China
| | - Xiaoqian Ma
- Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization, School of Electric Power, South China University of Technology, Guangdong, Guangzhou 510640, China
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Du B, Hu Y, Cheng T, Jiang Z, Wang Z, Zhu C. Low-temperature selective catalytic reduction of NO with NH 3 over an FeO x /β-MnO 2 composite. RSC Adv 2023; 13:6378-6388. [PMID: 36845597 PMCID: PMC9943891 DOI: 10.1039/d3ra00235g] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 02/13/2023] [Indexed: 02/24/2023] Open
Abstract
A series of Fe-modified β-MnO2 (FeO x /β-MnO2) composite catalysts were prepared by an impregnation method with β-MnO2 and ferro nitrate as raw materials. The structures and properties of the composites were systematically characterized and analyzed by X-ray diffraction, N2 adsorption-desorption, high-resolution electron microscopy, temperature-programmed reduction of H2, temperature-programmed desorption of NH3, and FTIR infrared spectroscopy. The deNO x activity, water resistance, and sulfur resistance of the composite catalysts were evaluated in a thermally fixed catalytic reaction system. The results indicated that the FeO x /β-MnO2 composite (Fe/Mn molar ratio of 0.3 and calcination temperature of 450 °C) had higher catalytic activity and a wider reaction temperature window compared with β-MnO2. The water resistance and sulfur resistance of the catalyst were enhanced. It reached 100% NO conversion efficiency with an initial NO concentration of 500 ppm, a gas hourly space velocity of 45 000 h-1, and a reaction temperature of 175-325 °C. The appropriate Fe/Mn molar ratio sample had a synergistic effect, affecting the morphology, redox properties, and acidic sites, and helped to improve the low-temperature NH3-SCR activity of the composite catalyst.
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Affiliation(s)
- Bo Du
- School of Resource and Environmental Engineering, Hefei University of Technology Hefei 230009 P. R. China +86 551 62901649 +86 551 62901523.,Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology Hefei 230009 P. R. China.,Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology Hefei 230009 P. R. China
| | - Yuting Hu
- School of Resource and Environmental Engineering, Hefei University of Technology Hefei 230009 P. R. China +86 551 62901649 +86 551 62901523.,Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology Hefei 230009 P. R. China.,Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology Hefei 230009 P. R. China
| | - Ting Cheng
- School of Resource and Environmental Engineering, Hefei University of Technology Hefei 230009 P. R. China +86 551 62901649 +86 551 62901523.,Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology Hefei 230009 P. R. China.,Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology Hefei 230009 P. R. China
| | - Zhaozhong Jiang
- School of Resource and Environmental Engineering, Hefei University of Technology Hefei 230009 P. R. China +86 551 62901649 +86 551 62901523.,Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology Hefei 230009 P. R. China.,Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology Hefei 230009 P. R. China
| | - Zhenzhen Wang
- School of Resource and Environmental Engineering, Hefei University of Technology Hefei 230009 P. R. China +86 551 62901649 +86 551 62901523.,Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology Hefei 230009 P. R. China.,Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology Hefei 230009 P. R. China
| | - Chengzhu Zhu
- School of Resource and Environmental Engineering, Hefei University of Technology Hefei 230009 P. R. China +86 551 62901649 +86 551 62901523.,Institute of Atmospheric Environment & Pollution Control, Hefei University of Technology Hefei 230009 P. R. China.,Key Laboratory of Nanominerals and Pollution Control of Anhui Higher Education Institutes, Hefei University of Technology Hefei 230009 P. R. China.,Low Temperature Denitration Engineering Research Center of Anhui Province Hefei 230001 P. R. China
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Xu Y, Wang P, Pu Y, Jiang L, Yang L, Jiang W, Yao L. MnCe/GAC-CNTs catalyst with high activity, SO2 and H2O tolerance for low-temperature NH3-SCR. Sep Purif Technol 2023. [DOI: 10.1016/j.seppur.2022.122498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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