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Goda MN, El-Aal MA, Magdy E, Said AEAA. The catalytic performance of FexMn1-xWO4 as novel wolframite-type nanocatalysts for the selective dehydration of methanol into dimethyl ether. MOLECULAR CATALYSIS 2023; 547:113350. [DOI: 10.1016/j.mcat.2023.113350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
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Rüther F, Baumgarten R, Ebert F, Gioria E, Naumann d'Alnoncourt R, Trunschke A, Rosowski F. Tuning catalysis by surface-deposition of elements on oxidation catalysts via atomic layer deposition. Catal Sci Technol 2023. [DOI: 10.1039/d2cy02184f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/31/2023]
Abstract
This study on surface-modifications of bulk oxidation catalysts with sub-monolayers of POx, BOx and MnOxvia atomic layer deposition demonstrates this method to be a powerful tool for tuning the performance in selective oxidations of light alkanes.
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Desseigne M, Madigou V, Coulet MV, Heintz O, Chevallier V, Arab M. Au/WO3 nanocomposite based photocatalyst for enhanced solar photocatalytic activity. J Photochem Photobiol A Chem 2022. [DOI: 10.1016/j.jphotochem.2022.114427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Shoukat H, Altaf AA, Hamayun M, Ullah S, Kausar S, Hamza M, Muhammad S, Badshah A, Rasool N, Imran M. Catalytic Oxidation of Toluene into Benzaldehyde and Benzyl Alcohol Using Molybdenum-Incorporated Manganese Oxide Nanomaterials. ACS OMEGA 2021; 6:19606-19615. [PMID: 34368547 PMCID: PMC8340403 DOI: 10.1021/acsomega.1c02163] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
Oxidation of toluene (an organic pollutant), into useful chemical products, is of great interest nowadays. However, efficient conversion of toluene under mild and sustainable conditions is a thought-provoking task. Here, we report MnMoO4 nanomaterials (CH1-CH2), synthesized through a very facile solvothermal approach. Catalytic efficiencies of MnMoO4 nanomaterials were evaluated by direct oxidation of toluene via C-H activation. Toluene was converted into benzaldehyde and benzyl alcohol in the presence of H2O2 as an oxidant at 80 °C. The reaction parameters, that is, catalyst dose, time, and toluene concentration, were varied to obtain the optimal conditions for the oxidation process. The 40.62% maximum toluene conversion rate was obtained after 18 h of oxidation activity with 0.06 g of catalyst CH1. A maximum of 78% benzaldehyde selectivity was obtained with 0.06 g of catalyst CH1 after 18 h of toluene oxidation activity. Also, 62.33% benzyl alcohol selectivity was achieved using 0.1 g of catalyst CH1 after 1 h of activity. Several catalytic cycles were run with CH1 to evaluate catalyst reusability. Potential % toluene conversion was obtained for up to six cycles and their turnover frequencies were found to be 1.94-1.01 s-1. FTIR spectra of catalyst CH1 before and after recovery indicate no significant change. The good conversion rate of toluene and efficient selectivity toward benzaldehyde and benzyl alcohol indicates the robustness and high potential of these catalysts to oxidize toluene under a milder, greener, and hazardous chlorine-free environment.
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Affiliation(s)
- Hamza Shoukat
- Department of Chemistry, University of Gujrat, Hafiz Hayat Campus, Gujrat 50700, Pakistan
| | - Ataf Ali Altaf
- Department of Chemistry, University of Okara, Okara 56300, Pakistan
- Catalysis and Energy Research Center, University of Okara, Okara 56300, Pakistan
| | - Muhammad Hamayun
- Department of Chemistry, University of Gujrat, Hafiz Hayat Campus, Gujrat 50700, Pakistan
| | - Shaheed Ullah
- Department of Chemistry, University of Okara, Okara 56300, Pakistan
| | - Samia Kausar
- Department of Chemistry, University of Gujrat, Hafiz Hayat Campus, Gujrat 50700, Pakistan
| | - Muhammad Hamza
- Department of Chemistry, University of Gujrat, Hafiz Hayat Campus, Gujrat 50700, Pakistan
| | - Shabbir Muhammad
- Department of Physics, College of Science, King Khalid University, Abha 61413, P.O. Box 9004, Saudi Arabia
| | - Amin Badshah
- Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Nasir Rasool
- Department of Chemistry, Government College University, Faisalabad 38000, Pakistan
| | - Muhammad Imran
- Department of Chemistry, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia
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Li X, Teschner D, Streibel V, Lunkenbein T, Masliuk L, Fu T, Wang Y, Jones T, Seitz F, Girgsdies F, Rosowski F, Schlögl R, Trunschke A. How to control selectivity in alkane oxidation? Chem Sci 2019; 10:2429-2443. [PMID: 30881671 PMCID: PMC6385647 DOI: 10.1039/c8sc04641g] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 12/20/2018] [Indexed: 11/21/2022] Open
Abstract
The well-defined particle morphology of crystalline MnWO4 catalysts investigated in the present study facilitates obtaining insight into the origin of selectivity limitations in alkane oxidation. Hydrothermal synthesis at variable pH values granted access to a series of phase-pure MnWO4 catalysts with particles ranging from cube-like (aspect ratio 1.5) to rod- or needle-like (aspect ratio 6.8) shapes. Kinetic studies reveal a strong dependence of the propane consumption rate on the particle shape. The true origin of the structure sensitivity was unraveled by comprehensive bulk and surface analysis using nitrogen adsorption, XRD, SEM, ADF-STEM, STEM-EELS, XPS, multi-laser excitation Raman and DRIFT/operando FTIR spectroscopies, temperature-programmed oxidation (TPO), in situ NEXAFS, and DFT calculations. The active phase is composed of a thin manganese oxy-hydroxide layer formed on the surface of crystalline MnWO4. The differences in catalytic performance within the series clearly illustrate that the structural motif as the most popular descriptor in oxidation catalysis is not essential, since all MnWO4 catalysts in the series under study exhibit the same bulk crystal structure and bulk chemical composition and are phase pure and homogenous. The variable particle shape serves as a proxy that reflects the formation of varying abundance of redox active Mn2+/Mn3+ surface sites, which correlates with catalytic activity. Operando FTIR spectroscopy directly confirms the formation of Mn-OH surface species by abstraction of hydrogen atoms from the propane molecule on nucleophilic oxygen atoms and suggests that active site regeneration occurs via oxidative dehydrogenation of Mn-OH species indicating a single-site nature of the active sites that does not allow four-electron reduction of molecular oxygen. Instead, intermediates are created that cause side reactions and lower the selectivity. The findings highlight fundamental design criteria that may be applied to advance the development of new alkane oxidation catalysts with improved selectivity.
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Affiliation(s)
- Xuan Li
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
- UniCat-BASF Joint Lab , Technische Universität Berlin , Sekr. EW K 01, Hardenbergstraße 36 , 10623 Berlin , Germany
| | - Detre Teschner
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
- Department of Heterogeneous Reactions , Max-Planck-Institut für Chemische Energiekonversion , Stiftstraße 34-36 , 45470 Mülheim a. d. Ruhr , Germany
| | - Verena Streibel
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
| | - Thomas Lunkenbein
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
| | - Liudmyla Masliuk
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
| | - Teng Fu
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
| | - Yuanqing Wang
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
- UniCat-BASF Joint Lab , Technische Universität Berlin , Sekr. EW K 01, Hardenbergstraße 36 , 10623 Berlin , Germany
| | - Travis Jones
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
| | - Friedrich Seitz
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
| | - Frank Girgsdies
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
| | - Frank Rosowski
- UniCat-BASF Joint Lab , Technische Universität Berlin , Sekr. EW K 01, Hardenbergstraße 36 , 10623 Berlin , Germany
- BASF SE , Process Research and Chemical Engineering , Heterogeneous Catalysis , Carl-Bosch-Straße 38 , 67056 Ludwigshafen , Germany
| | - Robert Schlögl
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
- Department of Heterogeneous Reactions , Max-Planck-Institut für Chemische Energiekonversion , Stiftstraße 34-36 , 45470 Mülheim a. d. Ruhr , Germany
| | - Annette Trunschke
- Department of Inorganic Chemistry , Fritz-Haber-Institut der Max-Planck-Gesellschaft , Faradayweg 4-6 , 14195 Berlin , Germany . ; Tel: +49 30 8413 4457
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