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Liu K, Yu Q, Wang B, Qin Q, Wei M, Fu Q. Low temperature selective catalytic reduction of nitric oxide with urea over activated carbon supported metal oxide catalysts. ENVIRONMENTAL TECHNOLOGY 2020; 41:808-821. [PMID: 30118387 DOI: 10.1080/09593330.2018.1511752] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Accepted: 08/02/2018] [Indexed: 06/08/2023]
Abstract
Selective catalytic reduction of nitrogen oxides (SCR) with loaded urea is a method for removing NO under oxygen-rich and low-temperature conditions, which can solve the inhibitory effect of oxygen on the catalyst and the slip of ammonia. In present study, a series of activated carbon (wo-AC, co-AC, cs-AC and nu-AC) supported metal (Mn, Fe, Co, Cu and Zn) oxide catalysts with loading urea were prepared by ultrasonic assisted impregnation. The catalysts were used for NO removal at 50-120°C and characterized by XRD, SEM, GFAAS, EDS, XPS, BET and FTIR techniques. The effects of activated carbon type, loaded active element, metal oxides loading, temperature fluctuation on catalytic activity and the catalytic stability were also studied in this paper. The results indicated that nutshell-based activated carbon was more suitable as a carrier than other activated carbons, and urea-10Mn/nu-AC catalyst yielded a higher NO conversion than other catalysts. Besides, for used activated carbons, the larger specific surface area, more micropores distribution and the larger number of hydroxyl group and cyano terminal group are beneficial to the catalytic process. Moreover, the downward trend of NO conversion with increasing temperature suggested the adsorption of reactant gases played a crucial role in the catalytic process of urea-SCR.
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Affiliation(s)
- Kaijie Liu
- State Environmental Protection Key Laboratory of Eco-Industry, School of Metallurgy, Northeastern University, Shenyang, People's Republic of China
| | - Qingbo Yu
- State Environmental Protection Key Laboratory of Eco-Industry, School of Metallurgy, Northeastern University, Shenyang, People's Republic of China
| | - Baolan Wang
- State Environmental Protection Key Laboratory of Eco-Industry, School of Metallurgy, Northeastern University, Shenyang, People's Republic of China
| | - Qin Qin
- State Environmental Protection Key Laboratory of Eco-Industry, School of Metallurgy, Northeastern University, Shenyang, People's Republic of China
| | - Mengqi Wei
- State Environmental Protection Key Laboratory of Eco-Industry, School of Metallurgy, Northeastern University, Shenyang, People's Republic of China
| | - Qi Fu
- State Environmental Protection Key Laboratory of Eco-Industry, School of Metallurgy, Northeastern University, Shenyang, People's Republic of China
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Zhang G, Huang X, Tang Z. Enhancing Water Resistance of a Mn-Based Catalyst for Low Temperature Selective Catalytic Reduction Reaction by Modifying Super Hydrophobic Layers. ACS APPLIED MATERIALS & INTERFACES 2019; 11:36598-36606. [PMID: 31529949 DOI: 10.1021/acsami.9b08451] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
OMS-2 catalysts exhibit excellent selective catalytic reduction (SCR) activity at low temperature but weak H2O resistance restricts its industrial application. To remarkably improve the water resistance of Mn-based catalysts is a key technical problem. In this work, the H2O endurance and self-cleaning properties of OMS-2 catalysts are remarkably improved by the facile process, construction of hydrophobic coating. The performance of the hydrophobic layer on the bulk OMS-2 catalyst surface could be effectively controlled by adjusting the polydimethylsiloxane (PDMS) vapor deposition temperature. It is discovered that the 200 °C catalyst obtained super hydrophobic properties and formed with a contact angle of 160.3°, which not only exhibited satisfactory NH3-SCR activity at low temperatures (140-300 °C) but also dramatically improved H2O endurance and self-cleaning performance. Moreover, the mechanism of improving H2O resistance and stability of the 200 °C catalyst was investigated in detail through a series of characterizations. Although the SCR activity of the 200 °C catalyst decreased slightly because of the combination of some active species (Oα and Mn3+) with PDMS, the H2O passivation of the active species was eliminated. The advantage of self-cleaning was confirmed by the analysis of surface species and simulation experiments, which could avoid the accumulation of intermediates on the surface and promote the stability of the OMS-2 catalyst for NH3-SCR at low temperature. This method of constructing special coating might be a huge step to remarkably improve the H2O endurance properties of the catalyst and provided a new concept for future industrial application.
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Affiliation(s)
- Guodong Zhang
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, and National Engineering Research Center for Fine Petrochemical Intermediates, Lanzhou Institute of Chemical Physics , Chinese Academy of Sciences , Lanzhou 730000 , PR China
| | - Xiaosheng Huang
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, and National Engineering Research Center for Fine Petrochemical Intermediates, Lanzhou Institute of Chemical Physics , Chinese Academy of Sciences , Lanzhou 730000 , PR China
| | - Zhicheng Tang
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, and National Engineering Research Center for Fine Petrochemical Intermediates, Lanzhou Institute of Chemical Physics , Chinese Academy of Sciences , Lanzhou 730000 , PR China
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Gu T, Gao F, Tang X, Yi H, Zhao S, Zaharaddeen S, Zhang R, Zhuang R, Ma Y. Fe-modified Ce-MnO x/ACF N catalysts for selective catalytic reduction of NO x by NH 3 at low-middle temperature. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:27940-27952. [PMID: 31350690 DOI: 10.1007/s11356-019-05976-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 07/12/2019] [Indexed: 06/10/2023]
Abstract
A series of MnOx/ACFN, Ce-MnOx/ACFN, and Fe-Ce-MnOx/ACFN catalysts on selective catalytic reduction (SCR) of NOx with NH3 at low-middle temperature had been successfully prepared through ultrasonic impregnation method, and the catalysts were characterized by SEM, XRD, BET, H2-TPR, NH3-TPD, XPS, and FT-IR spectroscopy, respectively. The results demonstrated that the 15 wt% Fe(1)-Ce(3)-MnOx(7)/ACFN catalyst achieved 90% NOx conversion (100~300 °C), good water resistance, and stability (175 °C). The excellent catalytic performance of the Fe(1)-Ce(3)-MnOx(7)/ACFN catalyst was mainly attributed to the interaction among Mn, Ce, and Fe. The doping of Fe promoted the dispersion of Ce and Mn and the formation of more Mn4+ and chemisorbed oxygen on the surface of a catalyst. This work laid a foundation for the successful application of active carbon fiber in the field of industrial denitrification, especially in the aspect of denitrification moving bed. Graphic abstract.
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Affiliation(s)
- Tian Gu
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
| | - Fengyu Gao
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
| | - Xiaolong Tang
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China.
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China.
| | - Honghong Yi
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
| | - Shunzheng Zhao
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
- Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
| | - Sani Zaharaddeen
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
| | - Runcao Zhang
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
| | - Ruijie Zhuang
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
| | - Yingli Ma
- Department of Environmental Engineering, School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, People's Republic of China
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Liu K, Yu Q, Wang B, Han Z, San J, Qin Q. Novel efficient U–Cu/CSAC catalyst for selective reduction of NO at low temperatures: preparation, characterization, evaluation and mechanism. NEW J CHEM 2019. [DOI: 10.1039/c9nj02740h] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Highly dispersed Cu0 nanoparticles and amorphous Cu2O supported on coconut shell-based activated carbon showed excellent LTU-SCR activity at low temperatures.
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Affiliation(s)
- Kaijie Liu
- School of Metallurgy
- Northeastern University
- Liaoning
- P. R. China
| | - Qingbo Yu
- School of Metallurgy
- Northeastern University
- Liaoning
- P. R. China
| | - Baolan Wang
- School of Metallurgy
- Northeastern University
- Liaoning
- P. R. China
| | - Zhicheng Han
- School of Metallurgy
- Northeastern University
- Liaoning
- P. R. China
| | - Junbo San
- School of Metallurgy
- Northeastern University
- Liaoning
- P. R. China
| | - Qin Qin
- School of Metallurgy
- Northeastern University
- Liaoning
- P. R. China
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