Adsorption/Oxidation of CHOH on VO. A Theoretical and Experimental Study
The adsorption/oxidation of CH 3 OH on V 2 O 5 was studied in previous work by mass spectrometric analysis of the reaction atmosphere, and by measuring the electrical properties (Hall effect) and total pressure of the system. Such data allowed a reaction pathway to be proposed. In the present work,...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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SAGE Publications
1997-07-01
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| Series: | Adsorption Science & Technology |
| Online Access: | https://doi.org/10.1177/026361749701500705 |
| _version_ | 1797282354694193152 |
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| author | Jorge Sambeth Alfredo Juan Luis Gambaro Horacio Thomas |
| author_facet | Jorge Sambeth Alfredo Juan Luis Gambaro Horacio Thomas |
| author_sort | Jorge Sambeth |
| collection | DOAJ |
| description | The adsorption/oxidation of CH 3 OH on V 2 O 5 was studied in previous work by mass spectrometric analysis of the reaction atmosphere, and by measuring the electrical properties (Hall effect) and total pressure of the system. Such data allowed a reaction pathway to be proposed. In the present work, the variations in the surface oxidation number have been calculated via balances in the C and H atoms in the reaction atmosphere and models of the (010) plane of V 2 O 5 and of CH 3 OH have also been utilized to find energetically favourable sites for the adsorption of CH 3 OH and its subsequent oxidation to H 2 CO. For this purpose, the variation in the total energy of the system was computed by Extended Hückel-type calculations (ASED, Atom Superposition and Electron Delocalization). From such experimental results, it was deduced that the H atoms are removed by the network oxygens and that methanol is adsorbed as the methoxy group. Such removal of H atoms has two consequences: high surface hydroxylation and surface reduction [V(5+) → V(4+)]. In support of these suggestions, the theoretical results have confirmed both the removal of H atoms and methoxy group formation, and have also revealed two possible adsorption sites for CH 3 OH on V 2 O 5 : the terminal oxygens (V=O) and the network bridging oxygens (V-O-V). |
| first_indexed | 2024-03-07T17:11:36Z |
| format | Article |
| id | doaj.art-4de681ab0a1f406b8a0a9089d745d01a |
| institution | Directory Open Access Journal |
| issn | 0263-6174 2048-4038 |
| language | English |
| last_indexed | 2024-03-07T17:11:36Z |
| publishDate | 1997-07-01 |
| publisher | SAGE Publications |
| record_format | Article |
| series | Adsorption Science & Technology |
| spelling | doaj.art-4de681ab0a1f406b8a0a9089d745d01a2024-03-03T00:57:51ZengSAGE PublicationsAdsorption Science & Technology0263-61742048-40381997-07-011510.1177/026361749701500705Adsorption/Oxidation of CHOH on VO. A Theoretical and Experimental StudyJorge Sambeth0Alfredo Juan1Luis Gambaro2Horacio Thomas3 Cindeca, Unlp Conicet, Calle 47, No. , 1900 La Plata, Argentina Plapiqui (Uns Conicet) and Departmento di Fisica. Universidad Nacional del Sur. Av. Alem 1253, 8000 Bahia Blanca, Argentina Cindeca, Unlp Conicet, Calle 47, No. , 1900 La Plata, Argentina Cindeca, Unlp Conicet, Calle 47, No. , 1900 La Plata, ArgentinaThe adsorption/oxidation of CH 3 OH on V 2 O 5 was studied in previous work by mass spectrometric analysis of the reaction atmosphere, and by measuring the electrical properties (Hall effect) and total pressure of the system. Such data allowed a reaction pathway to be proposed. In the present work, the variations in the surface oxidation number have been calculated via balances in the C and H atoms in the reaction atmosphere and models of the (010) plane of V 2 O 5 and of CH 3 OH have also been utilized to find energetically favourable sites for the adsorption of CH 3 OH and its subsequent oxidation to H 2 CO. For this purpose, the variation in the total energy of the system was computed by Extended Hückel-type calculations (ASED, Atom Superposition and Electron Delocalization). From such experimental results, it was deduced that the H atoms are removed by the network oxygens and that methanol is adsorbed as the methoxy group. Such removal of H atoms has two consequences: high surface hydroxylation and surface reduction [V(5+) → V(4+)]. In support of these suggestions, the theoretical results have confirmed both the removal of H atoms and methoxy group formation, and have also revealed two possible adsorption sites for CH 3 OH on V 2 O 5 : the terminal oxygens (V=O) and the network bridging oxygens (V-O-V).https://doi.org/10.1177/026361749701500705 |
| spellingShingle | Jorge Sambeth Alfredo Juan Luis Gambaro Horacio Thomas Adsorption/Oxidation of CHOH on VO. A Theoretical and Experimental Study Adsorption Science & Technology |
| title | Adsorption/Oxidation of CHOH on VO. A Theoretical and Experimental Study |
| title_full | Adsorption/Oxidation of CHOH on VO. A Theoretical and Experimental Study |
| title_fullStr | Adsorption/Oxidation of CHOH on VO. A Theoretical and Experimental Study |
| title_full_unstemmed | Adsorption/Oxidation of CHOH on VO. A Theoretical and Experimental Study |
| title_short | Adsorption/Oxidation of CHOH on VO. A Theoretical and Experimental Study |
| title_sort | adsorption oxidation of choh on vo a theoretical and experimental study |
| url | https://doi.org/10.1177/026361749701500705 |
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