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Dai C, Zhang Y, Liu N, Yu G, Wang N, Xu R, Chen B. Mechanistic insight into the effect of active site motif structures on direct oxidation of methane to methanol over Cu-ZSM-5. Phys Chem Chem Phys 2023; 25:24894-24903. [PMID: 37681261 DOI: 10.1039/d3cp01906c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/09/2023]
Abstract
Direct oxidation of methane to methanol (DMTM), a highly challenging reaction in C1 chemistry, has attracted lots of attention. Herein, we investigate the continuous H2O-mediated N2O-DMTM over a series of Cu-ZSM-5-n zeolites prepared by a solid-state ion-exchange method. Excellent CH3OH productivity (194.8 μmol gcat-1 h-1) and selectivity (67.1%) can be achieved over Cu-ZSM-5-0.3%, which surpasses most recently reported zeolite catalysts. The effect of the active site motif structure on the reaction was systematically investigated by the combined experimental and theoretical studies. It has been revealed that both the monomeric [Cu]+ and binuclear [Cu]+-[Cu]+ sites function to produce CH3OH, following the radical rebound mechanism, wherein the latter one plays a dominant role due to the synergistic effect of neighboring [Cu]+ that can efficiently reduce the N2O dissociation barrier to generate active oxygen for CH4 oxidation. Microkinetic modeling results further show that the dicopper site possesses a much higher net reaction rate (1.23 × 105 s-1) than the monomeric Cu site (0.962 s-1); moreover, H2O can shift the rate determining step from the CH3OH desorption step to the N2O dissociation step over the dicopper site, thereby efficiently favoring CH3OH production and resisting carbon deposition. Generally, the study in the present work would substantially favor other highly efficient catalyst designs.
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Affiliation(s)
- Chengna Dai
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, China.
| | - Yuchan Zhang
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, China.
| | - Ning Liu
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, China.
| | - Gangqiang Yu
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, China.
| | - Ning Wang
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, China.
| | - Ruinian Xu
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, China.
| | - Biaohua Chen
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, China.
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Dummer NF, Willock DJ, He Q, Howard MJ, Lewis RJ, Qi G, Taylor SH, Xu J, Bethell D, Kiely CJ, Hutchings GJ. Methane Oxidation to Methanol. Chem Rev 2022; 123:6359-6411. [PMID: 36459432 PMCID: PMC10176486 DOI: 10.1021/acs.chemrev.2c00439] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The direct transformation of methane to methanol remains a significant challenge for operation at a larger scale. Central to this challenge is the low reactivity of methane at conditions that can facilitate product recovery. This review discusses the issue through examination of several promising routes to methanol and an evaluation of performance targets that are required to develop the process at scale. We explore the methods currently used, the emergence of active heterogeneous catalysts and their design and reaction mechanisms and provide a critical perspective on future operation. Initial experiments are discussed where identification of gas phase radical chemistry limited further development by this approach. Subsequently, a new class of catalytic materials based on natural systems such as iron or copper containing zeolites were explored at milder conditions. The key issues of these technologies are low methane conversion and often significant overoxidation of products. Despite this, interest remains high in this reaction and the wider appeal of an effective route to key products from C-H activation, particularly with the need to transition to net carbon zero with new routes from renewable methane sources is exciting.
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Affiliation(s)
- Nicholas F. Dummer
- Max Planck−Cardiff Centre on the Fundamentals of Heterogeneous Catalysis FUNCAT, Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, CardiffCF10 3AT, United Kingdom
| | - David J. Willock
- Max Planck−Cardiff Centre on the Fundamentals of Heterogeneous Catalysis FUNCAT, Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, CardiffCF10 3AT, United Kingdom
| | - Qian He
- Department of Materials Science and Engineering, National University of Singapore, Singapore117575, Singapore
| | - Mark J. Howard
- Max Planck−Cardiff Centre on the Fundamentals of Heterogeneous Catalysis FUNCAT, Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, CardiffCF10 3AT, United Kingdom
| | - Richard J. Lewis
- Max Planck−Cardiff Centre on the Fundamentals of Heterogeneous Catalysis FUNCAT, Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, CardiffCF10 3AT, United Kingdom
| | - Guodong Qi
- National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan430071, P. R. China
- University of Chinese Academy of Sciences, Beijing100049, P. R. China
| | - Stuart H. Taylor
- Max Planck−Cardiff Centre on the Fundamentals of Heterogeneous Catalysis FUNCAT, Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, CardiffCF10 3AT, United Kingdom
| | - Jun Xu
- National Center for Magnetic Resonance in Wuhan, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan430071, P. R. China
- University of Chinese Academy of Sciences, Beijing100049, P. R. China
| | - Don Bethell
- Department of Chemistry, University of Liverpool, Crown Street, LiverpoolL69 7ZD, United Kingdom
| | - Christopher J. Kiely
- Department of Materials Science and Engineering, Lehigh University, 5 East Packer Avenue, Bethlehem, Pennsylvania18015, United States
| | - Graham J. Hutchings
- Max Planck−Cardiff Centre on the Fundamentals of Heterogeneous Catalysis FUNCAT, Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, CardiffCF10 3AT, United Kingdom
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Zhao G, Yan P, Procter K, Adesina A, Jin Y, Kennedy E, Stockenhuber M. Effect of Desilication on the Catalytic Activity of Fe-FER for Direct, Selective, Partial Oxidation of Methane. J Catal 2022. [DOI: 10.1016/j.jcat.2022.11.030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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4
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Liu N, Li Y, Dai C, Xu R, Yu G, Wang N, Chen B. H2O in situ induced active site structure dynamics for efficient methane direct oxidation to methanol over Fe-BEA zeolite. J Catal 2022. [DOI: 10.1016/j.jcat.2022.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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5
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Xue Z, Liu P, Li N, Ling L, Liu P, Shen X, Zhang R, Wang B. Effect of ZSM–5 with different active centers on methane partial oxidation. Molecular Catalysis 2022. [DOI: 10.1016/j.mcat.2022.112308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Movick WJ, Yun GN, Tyrone Ghampson I, Ted Oyama S. The Delplot kinetic method applied to systems with adsorbates: Hydrodeoxygenation of benzofuran on a bimetallic CoPd phosphide catalyst supported on KUSY. J Catal 2021. [DOI: 10.1016/j.jcat.2021.08.051] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Abstract
Microporous zeolite-type materials, with crystalline porous structures formed by well-defined channels and cages of molecular dimensions, have been widely employed as heterogeneous catalysts since the early 1960s, due to their wide variety of framework topologies, compositional flexibility and hydrothermal stability. The possible selection of the microporous structure and of the elements located in framework and extraframework positions enables the design of highly selective catalysts with well-defined active sites of acidic, basic or redox character, opening the path to their application in a wide range of catalytic processes. This versatility and high catalytic efficiency is the key factor enabling their use in the activation and conversion of different alkanes, ranging from methane to long chain n-paraffins. Alkanes are highly stable molecules, but their abundance and low cost have been two main driving forces for the development of processes directed to their upgrading over the last 50 years. However, the availability of advanced characterization tools combined with molecular modelling has enabled a more fundamental approach to the activation and conversion of alkanes, with most of the recent research being focused on the functionalization of methane and light alkanes, where their selective transformation at reasonable conversions remains, even nowadays, an important challenge. In this review, we will cover the use of microporous zeolite-type materials as components of mono- and bifunctional catalysts in the catalytic activation and conversion of C1+ alkanes under non-oxidative or oxidative conditions. In each case, the alkane activation will be approached from a fundamental perspective, with the aim of understanding, at the molecular level, the role of the active sites involved in the activation and transformation of the different molecules and the contribution of shape-selective or confinement effects imposed by the microporous structure.
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Affiliation(s)
- Pablo Del Campo
- Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avenida de los Naranjos s/n, 46022 Valencia, Spain.
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Zhao G, Chodyko K, Benhelal E, Adesina A, Kennedy E, Stockenhuber M. Methane oxidation by N2O over Fe-FER catalysts prepared by different methods: Nature of active iron species, stability of surface oxygen species and selectivity to products. J Catal 2021; 400:10-9. [DOI: 10.1016/j.jcat.2021.04.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Xu R, Liu N, Dai C, Li Y, Zhang J, Wu B, Yu G, Chen B. H 2 O-Built Proton Transfer Bridge Enhances Continuous Methane Oxidation to Methanol over Cu-BEA Zeolite. Angew Chem Int Ed Engl 2021; 60:16634-16640. [PMID: 33982395 DOI: 10.1002/anie.202105167] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Indexed: 11/09/2022]
Abstract
Direct oxidation of methane to methanol (DMTM) is a big challenge in C1 chemistry. We present a continuous N2 O-DMTM investigation by simultaneously introducing 10 vol % H2 O into the reaction system over Cu-BEA zeolites. Combining a D2 O isotopic tracer technique and ab initio molecular dynamics (AIMD) simulation, we for the first time demonstrate that the H2 O molecules can participate in the reaction through a proton transfer route, wherein the H2 O molecules can build a high-speed proton transfer bridge between the generated moieties of CH3 - and OH- over the evolved mono(μ-oxo) dicopper ([Cu-O-Cu]2+ ) active site, thereby pronouncedly boosting the CH3 OH selectivity (3.1→71.6 %), productivity (16.8→242.9 μmol gcat -1 h-1 ) and long-term reaction stability (10→70 h) relative to the scenario of absence of H2 O. Unravelling the proton transfer of H2 O over the dicopper [Cu-O-Cu]2+ site would substantially contribute to highly efficient catalyst designs for the continuous DMTM.
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Affiliation(s)
- Ruinian Xu
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, P. R. China
| | - Ning Liu
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, P. R. China
| | - Chengna Dai
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, P. R. China
| | - Yan Li
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Jie Zhang
- State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Bin Wu
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, P. R. China
| | - Gangqiang Yu
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, P. R. China
| | - Biaohua Chen
- Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, P. R. China.,Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, P. R. China
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10
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Xu R, Liu N, Dai C, Li Y, Zhang J, Wu B, Yu G, Chen B. H
2
O‐Built Proton Transfer Bridge Enhances Continuous Methane Oxidation to Methanol over Cu‐BEA Zeolite. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202105167] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ruinian Xu
- Faculty of Environment and Life Beijing University of Technology Beijing 100124 P. R. China
| | - Ning Liu
- Faculty of Environment and Life Beijing University of Technology Beijing 100124 P. R. China
| | - Chengna Dai
- Faculty of Environment and Life Beijing University of Technology Beijing 100124 P. R. China
| | - Yan Li
- State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 P. R. China
| | - Jie Zhang
- State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 P. R. China
| | - Bin Wu
- Faculty of Environment and Life Beijing University of Technology Beijing 100124 P. R. China
| | - Gangqiang Yu
- Faculty of Environment and Life Beijing University of Technology Beijing 100124 P. R. China
| | - Biaohua Chen
- Faculty of Environment and Life Beijing University of Technology Beijing 100124 P. R. China
- Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical Engineering Changzhou University Changzhou 213164 P. R. China
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Kang Y, Li Z, Lv X, Song W, Wei Y, Zhang X, Liu J, Zhao Z. Active oxygen promoted electrochemical conversion of methane on two-dimensional carbide (MXenes): From stability, reactivity and selectivity. J Catal 2021. [DOI: 10.1016/j.jcat.2020.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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12
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Mousavian P, Esrafili MD. Methane oxidation into methanol catalyzed by TM-anchored C24N24 nanoclusters (TM = Fe, Co and Ni): A DFT study. INORG CHEM COMMUN 2020; 122:108317. [DOI: 10.1016/j.inoche.2020.108317] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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13
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Yun G, Tyrone Ghampson I, Movick WJ, Vargheese V, Kobayashi Y, Ted Oyama S. Applicability of the Delplot method for the determination of catalytic reaction sequences: Hydrodeoxygenation of γ-valerolactone on Ni2P/MCM-41. Chem Eng Sci 2020; 223:115697. [DOI: 10.1016/j.ces.2020.115697] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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14
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Kvande K, Pappas DK, Borfecchia E, Lomachenko KA. Advanced X‐ray Absorption Spectroscopy Analysis to Determine Structure‐Activity Relationships for Cu‐Zeolites in the Direct Conversion of Methane to Methanol. ChemCatChem 2020. [DOI: 10.1002/cctc.201902371] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Karoline Kvande
- Centre for Materials Science and Nanotechnology Department of Chemistry University of Oslo Sem Sælands vei 26 0371 Oslo Norway
| | - Dimitrios K. Pappas
- Centre for Materials Science and Nanotechnology Department of Chemistry University of Oslo Sem Sælands vei 26 0371 Oslo Norway
| | - Elisa Borfecchia
- Department of Chemistry, NIS Center and INSTM Reference Center University of Turin Via P. Giuria 7 10125 Turin Italy
| | - Kirill A. Lomachenko
- European Synchrotron Radiation Facility 71 Avenue des Martyrs, CS 40220 Grenoble Cedex 9 38043 France
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15
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Zhao G, Adesina A, Kennedy E, Stockenhuber M. Formation of Surface Oxygen Species and the Conversion of Methane to Value-Added Products with N2O as Oxidant over Fe-Ferrierite Catalysts. ACS Catal 2019. [DOI: 10.1021/acscatal.9b03466] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Guangyu Zhao
- Chemical Engineering, School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | | | - Eric Kennedy
- Chemical Engineering, School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia
| | - Michael Stockenhuber
- Chemical Engineering, School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia
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16
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Shi Y, Liu S, Liu Y, Huang W, Guan G, Zuo Z. Quasicatalytic and catalytic selective oxidation of methane to methanol over solid materials: a review on the roles of water. Catalysis Reviews 2019. [DOI: 10.1080/01614940.2019.1674475] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Yayun Shi
- Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Shizhong Liu
- Department of Chemistry, Stony Brook University, New York, NY, USA
| | - Yiming Liu
- Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Wei Huang
- Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan, Shanxi, China
| | - Guoqing Guan
- Institute of Regional Innovation (IRI), Hirosaki University, Aomori, Japan
| | - Zhijun Zuo
- Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan, Shanxi, China
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18
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Raynes S, Shah MA, Taylor RA. Direct conversion of methane to methanol with zeolites: towards understanding the role of extra-framework d-block metal and zeolite framework type. Dalton Trans 2019; 48:10364-10384. [DOI: 10.1039/c9dt00922a] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
This Perspective article highlights the latest advances in the field of direct methane to methanol conversion by zeolites containing first row, extra-framework d-block metals (Mn, Fe, Co, Ni, Cu and Zn).
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Affiliation(s)
- Samuel Raynes
- Department of Chemistry
- Durham University
- Durham DH1 3LE
- UK
| | - Meera A. Shah
- Department of Chemistry
- Durham University
- Durham DH1 3LE
- UK
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Richards N, Nowicka E, Carter JH, Morgan DJ, Dummer NF, Golunski S, Hutchings GJ. Investigating the Influence of Fe Speciation on N 2O Decomposition Over Fe-ZSM-5 Catalysts. Top Catal 2018; 61:1983-1992. [PMID: 30930588 PMCID: PMC6411129 DOI: 10.1007/s11244-018-1024-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The influence of Fe speciation on the decomposition rates of N2O over Fe-ZSM-5 catalysts prepared by Chemical Vapour Impregnation were investigated. Various weight loadings of Fe-ZSM-5 catalysts were prepared from the parent zeolite H-ZSM-5 with a Si:Al ratio of 23 or 30. The effect of Si:Al ratio and Fe weight loading was initially investigated before focussing on a single weight loading and the effects of acid washing on catalyst activity and iron speciation. UV/Vis spectroscopy, surface area analysis, XPS and ICP-OES of the acid washed catalysts indicated a reduction of ca. 60% of Fe loading when compared to the parent catalyst with a 0.4 wt% Fe loading. The TOF of N2O decomposition at 600 °C improved to 3.99 × 103 s-1 over the acid washed catalyst which had a weight loading of 0.16%, in contrast, the parent catalyst had a TOF of 1.60 × 103 s-1. Propane was added to the gas stream to act as a reductant and remove any inhibiting oxygen species that remain on the surface of the catalyst. Comparison of catalysts with relatively high and low Fe loadings achieved comparable levels of N2O decomposition when propane is present. When only N2O is present, low metal loading Fe-ZSM-5 catalysts are not capable of achieving high conversions due to the low proximity of active framework Fe3+ ions and extra-framework ɑ-Fe species, which limits oxygen desorption. Acid washing extracts Fe from these active sites and deposits it on the surface of the catalyst as FexOy, leading to a drop in activity. The Fe species present in the catalyst were identified using UV/Vis spectroscopy and speculate on the active species. We consider high loadings of Fe do not lead to an active catalyst when propane is present due to the formation of FexOy nanoparticles and clusters during catalyst preparation. These are inactive species which lead to a decrease in overall efficiency of the Fe ions and consequentially a lower TOF.
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Affiliation(s)
- Nia Richards
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT UK
| | - Ewa Nowicka
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT UK
| | - James H. Carter
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT UK
| | - David J. Morgan
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT UK
| | - Nicholas F. Dummer
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT UK
| | - Stanislaw Golunski
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT UK
| | - Graham J. Hutchings
- Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT UK
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