1
|
Feng S, Li Z, Shen B, Yuan P, Ma J, Wang Z, Kong W. An overview of the deactivation mechanism and modification methods of the SCR catalysts for denitration from marine engine exhaust. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 317:115457. [PMID: 35751261 DOI: 10.1016/j.jenvman.2022.115457] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 11/27/2021] [Accepted: 05/28/2022] [Indexed: 06/15/2023]
Abstract
Selective catalytic reduction (SCR) technology is currently the most effective deNOx technology and has broad application prospects. Moreover, there is a large NOx content in marine engine exhaust. However, the marine engine SCR catalyst will be affected by heavy metals, SO2, H2O(g), hydrocarbons (HC) and particulate matter (PM) in the exhaust, which will hinder the removal of NOx via SCR. Furthermore, due to the high loading operation of the marine engine and the regeneration of the diesel particulate filter (DPF), the exhaust temperature of the engine may exceed 600 °C, which leads to sintering of the SCR catalysts. Therefore, the development of new catalysts with good tolerances to the above emissions and process parameters is of great significance for further reducing NOx from marine engines. In this work, we first elaborate on the mechanism of the SCR catalyst poisoning caused by marine engine emissions, as well as the working mechanism of SCR catalysts affected by the engine exhaust temperature. Second, we also summarize the current technologies for improving the properties of SCR catalysts with the aim of enhancing the resistance and stability under complex working conditions. Finally, the challenges and perspectives associated with the performance optimization and technology popularization of marine SCR systems are discussed and proposed further. Consequently, this review may provide a valuable reference and inspiration for the development of catalysts and improvement in the denitration ability of SCR systems matched with marine engines.
Collapse
Affiliation(s)
- Shuo Feng
- School of Energy and Environmental Engineering, Tianjin Key Laboratory of Clean Energy and Pollution Control, Hebei University of Technology, Tianjin, 300401, China
| | - Zhaoming Li
- School of Energy and Environmental Engineering, Tianjin Key Laboratory of Clean Energy and Pollution Control, Hebei University of Technology, Tianjin, 300401, China
| | - Boxiong Shen
- School of Energy and Environmental Engineering, Tianjin Key Laboratory of Clean Energy and Pollution Control, Hebei University of Technology, Tianjin, 300401, China.
| | - Peng Yuan
- School of Energy and Environmental Engineering, Tianjin Key Laboratory of Clean Energy and Pollution Control, Hebei University of Technology, Tianjin, 300401, China; School of Chemical Engineering and Technology, Hebei University of Technology, Tianjin, 300130, China.
| | - Jiao Ma
- School of Energy and Environmental Engineering, Tianjin Key Laboratory of Clean Energy and Pollution Control, Hebei University of Technology, Tianjin, 300401, China
| | - Zhuozhi Wang
- School of Energy and Environmental Engineering, Tianjin Key Laboratory of Clean Energy and Pollution Control, Hebei University of Technology, Tianjin, 300401, China
| | - Wenwen Kong
- School of Energy and Environmental Engineering, Tianjin Key Laboratory of Clean Energy and Pollution Control, Hebei University of Technology, Tianjin, 300401, China
| |
Collapse
|
2
|
Lee K, Choi B. HC-SCR system combining Ag/Al2O3 and Pd/Al2O3 catalysts with resistance to hydrothermal aging for simultaneous removal of NO, HC, and CO. J IND ENG CHEM 2021. [DOI: 10.1016/j.jiec.2021.06.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
|
3
|
Le MT, Singh S, Nguyen-Quang M, Ngo AB, Brückner A, Armbruster U. Insight into the properties of MnO 2-Co 3O 4-CeO 2 catalyst series for the selective catalytic reduction of NO x by C 3H 6 and NH 3. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 784:147394. [PMID: 34088029 DOI: 10.1016/j.scitotenv.2021.147394] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 04/21/2021] [Accepted: 04/23/2021] [Indexed: 06/12/2023]
Abstract
A series of MnO2-Co3O4-CeO2 catalysts with different ceria loading (0.75, 1.26 and 1.88 Ce/Mn molar ratio) were synthesized by a co-precipitation technique and the catalytic activity was tested for selective catalytic reduction of NOx by C3H6 or NH3. The catalysts were characterized by various physicochemical techniques to examine the effect of ceria loading on the properties of catalysts, such as crystallinity of metal species, surface area, porosity, and acidity using physical adsorption analysis, SEM-EDX, H2-TPR, XRD, NH3-TPD and in-situ FTIR spectroscopy. Ceria loading had a significant effect on the reduction of NOx, with the catalyst having low amount of ceria loading (Ce/Mn = 0.75) showing excellent performance at low-temperature conditions, but the activity declined at higher temperature. The high ceria loading (Ce/Mn = 1.88) catalyst showed poor activity compared to the counterparts owing to the lower number of acid sites and the resulting lower adsorption capacity.
Collapse
Affiliation(s)
- Minh Thang Le
- Department of Organic and Petrochemical Technology, School of Chemical Engineering, Hanoi University of Science and Technology, 1 Dai Co Viet, Hanoi 10000, Viet Nam.
| | - Sharanjit Singh
- Department of Organic and Petrochemical Technology, School of Chemical Engineering, Hanoi University of Science and Technology, 1 Dai Co Viet, Hanoi 10000, Viet Nam
| | - Minh Nguyen-Quang
- Department of Organic and Petrochemical Technology, School of Chemical Engineering, Hanoi University of Science and Technology, 1 Dai Co Viet, Hanoi 10000, Viet Nam
| | - Anh Binh Ngo
- Leibniz Institute for Catalysis, Albert-Einstein-Straße 29a, D-18059 Rostock, Germany
| | - Angelika Brückner
- Leibniz Institute for Catalysis, Albert-Einstein-Straße 29a, D-18059 Rostock, Germany
| | - Udo Armbruster
- Leibniz Institute for Catalysis, Albert-Einstein-Straße 29a, D-18059 Rostock, Germany
| |
Collapse
|
4
|
Zhao G, Liang H, Xu H, Li C, Tan Q, Zhang D. Catalytic wet peroxide degradation of acrylonitrile wastewater by ordered mesoporous Ag/CeO 2: synthesis, performance and kinetics. RSC Adv 2021; 11:15959-15968. [PMID: 35481213 PMCID: PMC9030448 DOI: 10.1039/d1ra01258d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 03/12/2021] [Indexed: 11/28/2022] Open
Abstract
Ordered mesoporous Ag/CeO2 catalysts have been successfully synthesized by a microwave assisted soft template method. The morphology, structure and chemical composition of the catalyst were characterized by XRD, N2 adsorption-desorption, SEM, EDS, TEM and XPS. The study of catalytic performance and reaction kinetics of organic matter degradation in acrylonitrile wastewater was performed in a catalytic wet peroxide (CWPO) system. The degradation pathways of organic matter in acrylonitrile wastewater were elucidated by temporal evolution of intermediates and final products detected by GC/MS analysis along with a continuous flow experiment study. The results show that the Ag/CeO2 has an ordered mesoporous structure, the specific surface area is 91.4-118.2 m2 g-1 and the average pore size is 12.63-16.86 nm. 0.4-Ag/CeO2 showed the best catalytic performance, the COD removal rate reached 94.6%, which was 30% higher than that of CeO2. The degradation is in accordance with the second-order reaction kinetics of the Arrhenius empirical model and Langmuir-Hinshelwood kinetic model. However the latter fits better, and the linear correlation coefficient R 2 is more than 0.98, which describes the adsorption catalytic mechanism of Ag/CeO2. According to the analysis by GC/MS, the organic compounds in acrylonitrile wastewater oxidized into intermediate compounds and other small compounds, then are further oxidized into carbon dioxide and water. The catalytic activity of Ag/CeO2 was the result of the combination of Lewis acid-base position of CeO2 and redox cycle of Ce3+/Ce4+.
Collapse
Affiliation(s)
- Guozheng Zhao
- School of Environmental & Safety Engineering, Liaoning Petrochemical University Liaoning Fushun 113001 China
| | - Hui Liang
- School of Environmental & Safety Engineering, Liaoning Petrochemical University Liaoning Fushun 113001 China
| | - Hongzhu Xu
- School of Environmental & Safety Engineering, Liaoning Petrochemical University Liaoning Fushun 113001 China
| | - Changbo Li
- School of Environmental & Safety Engineering, Liaoning Petrochemical University Liaoning Fushun 113001 China
| | - Qingwei Tan
- School of Environmental & Safety Engineering, Liaoning Petrochemical University Liaoning Fushun 113001 China
| | - Daihang Zhang
- School of Environmental & Safety Engineering, Liaoning Petrochemical University Liaoning Fushun 113001 China
| |
Collapse
|
5
|
Lee K, Choi B, Lee C, Oh K. Effects of SiO2/Al2O3 ratio, reaction atmosphere and metal additive on de-NOx performance of HC-SCR over Cu-based ZSM-5. J IND ENG CHEM 2020. [DOI: 10.1016/j.jiec.2020.07.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
6
|
Selective catalytic reduction of NOx with ethanol and other C1–4 oxygenates over Ag/Al2O3 catalysts: A review. Front Chem Sci Eng 2019. [DOI: 10.1007/s11705-019-1847-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
7
|
Plasma-Assisted Selective Catalytic Reduction for Low-Temperature Removal of NOx and Soot Simulant. Catalysts 2019. [DOI: 10.3390/catal9100853] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The challenge that needs to be overcome regarding the removal of nitrogen oxides (NOx) and soot from exhaust gases is the low activity of the selective catalytic reduction of NOx at temperatures fluctuating from 150 to 350 °C. The primary goal of this work was to enhance the conversion of NOx and soot simulant by employing a Ag/α-Al2O3 catalyst coupled with dielectric barrier discharge plasma. The results demonstrated that the use of a plasma-catalyst process at low operating temperatures increased the removal of both NOx and naphthalene (soot simulant). Moreover, the soot simulant functioned as a reducing agent for NOx removal, but with low NOx conversion. The high efficiency of NOx removal required the addition of hydrocarbon fuel. In summary, the combined use of the catalyst and plasma (specific input energy, SIE ≥ 60 J/L) solved the poor removal of NOx and soot at low operating temperatures or during temperature fluctuations in the range of 150–350 °C. Specifically, highly efficient naphthalene removal was achieved with low-temperature adsorption on the catalyst followed by the complete decomposition by the plasma-catalyst at 350 °C and SIE of 90 J/L.
Collapse
|
8
|
Bimetallic AgFe Systems on Mordenite: Effect of Cation Deposition Order in the NO Reduction with C3H6/CO. Catalysts 2019. [DOI: 10.3390/catal9010058] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Mono- and bimetallic systems of Ag, Fe, and Ag–Fe exchanged in sodium mordenite zeolite were studied in the reaction of NO reduction. The transition metal cations Ag and Fe were introduced by ion exchange method both at room temperature and 60 °C; modifying the order of component deposition in bimetallic systems. These materials were characterized by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), ultraviolet-visible spectroscopy (UV-Vis), X-Ray photoelectron Spectroscopy (XPS) and High-resolution transmission electron microscopy (HR-TEM). The XPS and UV–Vis spectra of bimetallic samples revealed that under certain preparation conditions Ag+ is reduced with the participation of the Fe2+/Fe3+ ions transition and is present in the form of a Ag reduced state in different proportions of Agm clusters and Ag0 NPs, influenced by the cation deposition order. The catalytic results in the NO reduction reaction using C3H6/CO under an oxidizing atmosphere show also that the order of exchange of Ag and Fe cations in mordenite has a strong effect on catalytic active sites for the reduction of NO.
Collapse
|