Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base Properties
The catalytic activity of zeolites is often related to their acid–base properties. In this work, the relationship between the value of apparent activation energy of ethanol dehydration, measured in a fixed bed reactor and by means of a temperature-programmed surface reaction (TPSR) depending on the...
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MDPI AG
2022-01-01
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| Series: | Catalysts |
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| Online Access: | https://www.mdpi.com/2073-4344/12/1/51 |
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| author | Pavel Čičmanec Jiří Kotera Jan Vaculík Roman Bulánek |
| author_facet | Pavel Čičmanec Jiří Kotera Jan Vaculík Roman Bulánek |
| author_sort | Pavel Čičmanec |
| collection | DOAJ |
| description | The catalytic activity of zeolites is often related to their acid–base properties. In this work, the relationship between the value of apparent activation energy of ethanol dehydration, measured in a fixed bed reactor and by means of a temperature-programmed surface reaction (TPSR) depending on the amount of ethanol in the zeolite lattice and the value of activation energy of H/D exchange as a measure of acid–base properties of <b>MFI</b> and <b>CHA</b> zeolites, was studied. Tests in a fixed bed reactor were unable to provide reliable reaction kinetics data due to internal diffusion limitations and rapid catalyst deactivation. Only the TPSR method was able to provide activation energy values comparable to the activation energy values obtained from the H/D exchange rate measurements. In addition, for <b>CHA</b> zeolite, it has been shown that the values of ethanol dehydration activation energies depend on the amount of ethanol in the <b>CHA</b> framework, and this effect can be attributed to the substrate clustering effects supporting the deprotonation of zeolite Brønsted centers. |
| first_indexed | 2024-03-10T01:45:44Z |
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| institution | Directory Open Access Journal |
| issn | 2073-4344 |
| language | English |
| last_indexed | 2024-03-10T01:45:44Z |
| publishDate | 2022-01-01 |
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| spelling | doaj.art-f4bfca5c277e42d9ab269b1b9da86cf62023-11-23T13:16:18ZengMDPI AGCatalysts2073-43442022-01-011215110.3390/catal12010051Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base PropertiesPavel Čičmanec0Jiří Kotera1Jan Vaculík2Roman Bulánek3Department of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, CZ-532 10 Pardubice, Czech RepublicDepartment of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, CZ-532 10 Pardubice, Czech RepublicDepartment of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, CZ-532 10 Pardubice, Czech RepublicDepartment of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, CZ-532 10 Pardubice, Czech RepublicThe catalytic activity of zeolites is often related to their acid–base properties. In this work, the relationship between the value of apparent activation energy of ethanol dehydration, measured in a fixed bed reactor and by means of a temperature-programmed surface reaction (TPSR) depending on the amount of ethanol in the zeolite lattice and the value of activation energy of H/D exchange as a measure of acid–base properties of <b>MFI</b> and <b>CHA</b> zeolites, was studied. Tests in a fixed bed reactor were unable to provide reliable reaction kinetics data due to internal diffusion limitations and rapid catalyst deactivation. Only the TPSR method was able to provide activation energy values comparable to the activation energy values obtained from the H/D exchange rate measurements. In addition, for <b>CHA</b> zeolite, it has been shown that the values of ethanol dehydration activation energies depend on the amount of ethanol in the <b>CHA</b> framework, and this effect can be attributed to the substrate clustering effects supporting the deprotonation of zeolite Brønsted centers.https://www.mdpi.com/2073-4344/12/1/51chabaziteMFIzeolite acid–base propertiesethanol dehydrationsubstrate clusteringtemperature programmed surface reaction |
| spellingShingle | Pavel Čičmanec Jiří Kotera Jan Vaculík Roman Bulánek Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base Properties Catalysts chabazite MFI zeolite acid–base properties ethanol dehydration substrate clustering temperature programmed surface reaction |
| title | Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base Properties |
| title_full | Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base Properties |
| title_fullStr | Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base Properties |
| title_full_unstemmed | Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base Properties |
| title_short | Influence of Substrate Concentration on Kinetic Parameters of Ethanol Dehydration in MFI and CHA Zeolites and Relation of These Kinetic Parameters to Acid–Base Properties |
| title_sort | influence of substrate concentration on kinetic parameters of ethanol dehydration in mfi and cha zeolites and relation of these kinetic parameters to acid base properties |
| topic | chabazite MFI zeolite acid–base properties ethanol dehydration substrate clustering temperature programmed surface reaction |
| url | https://www.mdpi.com/2073-4344/12/1/51 |
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