Experimental and theoretical IR study of methanol and ethanol conversion over H-SAPO-34
| Autor: | Hemelsoet, K.L.J., Ghysels, A., Mores, D., De Wispelaere, K., Van Speybroeck, V., Weckhuysen, B.M., Waroquier, M., Inorganic Chemistry and Catalysis, Sub Inorganic Chemistry and Catalysis |
|---|---|
| Přispěvatelé: | Inorganic Chemistry and Catalysis, Sub Inorganic Chemistry and Catalysis |
| Jazyk: | angličtina |
| Rok vydání: | 2011 |
| Předmět: |
REACTION-MECHANISM
TO-OLEFIN CATALYSIS Ab initio Analytical chemistry Infrared spectroscopy 02 engineering and technology FUNCTIONAL THEORY CALCULATIONS 010402 general chemistry DFT calculations 01 natural sciences 7. Clean energy Catalysis BRONSTED ACID SITES chemistry.chemical_compound Adsorption Physisorption Ir Molecule Methanol to hydrocarbons AB-INITIO Chemistry H-sapo-34 DER-WAALS COMPLEXES General Chemistry Normal mode analysis Science General 021001 nanoscience & nanotechnology SOLID-STATE NMR 0104 chemical sciences BLOCK HESSIAN APPROACH Solid-state nuclear magnetic resonance In situ DRIFT measurements SILICOALUMINOPHOSPHATE MOLECULAR-SIEVES NORMAL-MODE ANALYSIS Methanol 0210 nano-technology |
| Zdroj: | Catalysis Today, 177(1), 12. Elsevier CATALYSIS TODAY Catalysis Today |
| ISSN: | 0920-5861 |
| Popis: | Theoretical and experimental IR data are combined to gain insight into the methanol and ethanol conversion over an acidic H-SAPO-34 catalyst. The theoretical simulations use a large finite cluster and the initial physisorption energy of both alcohols is calculated. Dispersive contributions turn out to be vital and ethanol adsorbs stronger than methanol with approximately 14 kJ mol(-1). Calculated IR spectra of the alcohols and of formed aromatic cations upon conversion are also analyzed and support the peak assignment of the experimental in situ DRIFT spectra, in particular for the C-H and C=C regions. Theoretical IR spectra of the gas phase compounds are compared with those of the molecules loaded in a SAPO cluster and the observed shifts of the peak positions are discussed. To get a better understanding of these framework-guest interactions, a new theoretical procedure is proposed based on a normal mode analysis. A cumulative overlap function is defined and enables the characterization of individual peaks as well as induced frequency shifts upon adsorption. (C) 2010 Elsevier B. V. All rights reserved. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect