Abstract
The primary objective of the present work is to obtain new insight into the reaction mechanism of the zeolite catalyzed methanol-to-hydrocarbons (MTH) reaction. It was decided to use both experimental and computational techniques to reach this goal. An investigation of the n-butene + methanol system was therefore initiated. Over time, it became apparent that it was possible to determine the rate for the methylation of n-butene by methanol. The ethene and propene systems were therefore reexamined in order to collect kinetic information also for those cases. With the development of user-friendly quantum chemistry programs such as the Gaussian suite of programs, the possibility of applying quantum chemical methods to many types of problems has become readily available even for non-experts. When performing mechanistic studies, there is quite often a considerable synergy effect when combining experimental and computational approaches. The methylation reactions mentioned above turned out to be an issue well suited for quantum chemical investigations. The incentive for examining the halomethane reactivity was the clear analogy to the MTH reaction system. Alkene dimerization was also a reaction readily examined with quantum chemistry. As discussed in the introduction of this thesis, polymethylbenzenes, or their cationic counterparts, are suspected to be key
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Citation Formats
Svelle, Stian.
An experimental and theoretical study of reaction steps relevant to the methanol-to-hydrocarbons reaction.
Norway: N. p.,
2004.
Web.
Svelle, Stian.
An experimental and theoretical study of reaction steps relevant to the methanol-to-hydrocarbons reaction.
Norway.
Svelle, Stian.
2004.
"An experimental and theoretical study of reaction steps relevant to the methanol-to-hydrocarbons reaction."
Norway.
@misc{etde_20646873,
title = {An experimental and theoretical study of reaction steps relevant to the methanol-to-hydrocarbons reaction}
author = {Svelle, Stian}
abstractNote = {The primary objective of the present work is to obtain new insight into the reaction mechanism of the zeolite catalyzed methanol-to-hydrocarbons (MTH) reaction. It was decided to use both experimental and computational techniques to reach this goal. An investigation of the n-butene + methanol system was therefore initiated. Over time, it became apparent that it was possible to determine the rate for the methylation of n-butene by methanol. The ethene and propene systems were therefore reexamined in order to collect kinetic information also for those cases. With the development of user-friendly quantum chemistry programs such as the Gaussian suite of programs, the possibility of applying quantum chemical methods to many types of problems has become readily available even for non-experts. When performing mechanistic studies, there is quite often a considerable synergy effect when combining experimental and computational approaches. The methylation reactions mentioned above turned out to be an issue well suited for quantum chemical investigations. The incentive for examining the halomethane reactivity was the clear analogy to the MTH reaction system. Alkene dimerization was also a reaction readily examined with quantum chemistry. As discussed in the introduction of this thesis, polymethylbenzenes, or their cationic counterparts, are suspected to be key intermediates in the MTH reaction. It was therefore decided to investigate the intrinsic reactivity of these species in the gas-phase by employing sophisticated mass spectrometric (MS) techniques in collaboration with the MS group at the Department of Chemistry, University of Oslo The data thus obtained will also be compared with results from an ongoing computational study on gas phase polymethylbenzenium reactivity. 6 papers presenting various studies are included. The titles are: 1) A Theoretical Investigation of the Methylation of Alkenes with Methanol over Acidic Zeolites. 2) A Theoretical Investigation of the Methylation of Alkenes with Methanol over Acidic Zeolites. 3) Theoretical Investigation of the Dimerization of Linear Alkenes Catalyzed by Acidic Zeolites. 4) Kinetic studies of zeolite-catalyzed methylation reactions. 5) Kinetic studies of zeolite catalyzed methylation reactions. 2. Coreaction of [''1''2C]propene or [''1''2C]n-butene and [''1''3C]methanol. 6) The intermediates in the methanol-to-hydrocarbons (MTH) reaction: A gas phase study of the reactivity of polymethylbenzenium cations.}
place = {Norway}
year = {2004}
month = {Jul}
}
title = {An experimental and theoretical study of reaction steps relevant to the methanol-to-hydrocarbons reaction}
author = {Svelle, Stian}
abstractNote = {The primary objective of the present work is to obtain new insight into the reaction mechanism of the zeolite catalyzed methanol-to-hydrocarbons (MTH) reaction. It was decided to use both experimental and computational techniques to reach this goal. An investigation of the n-butene + methanol system was therefore initiated. Over time, it became apparent that it was possible to determine the rate for the methylation of n-butene by methanol. The ethene and propene systems were therefore reexamined in order to collect kinetic information also for those cases. With the development of user-friendly quantum chemistry programs such as the Gaussian suite of programs, the possibility of applying quantum chemical methods to many types of problems has become readily available even for non-experts. When performing mechanistic studies, there is quite often a considerable synergy effect when combining experimental and computational approaches. The methylation reactions mentioned above turned out to be an issue well suited for quantum chemical investigations. The incentive for examining the halomethane reactivity was the clear analogy to the MTH reaction system. Alkene dimerization was also a reaction readily examined with quantum chemistry. As discussed in the introduction of this thesis, polymethylbenzenes, or their cationic counterparts, are suspected to be key intermediates in the MTH reaction. It was therefore decided to investigate the intrinsic reactivity of these species in the gas-phase by employing sophisticated mass spectrometric (MS) techniques in collaboration with the MS group at the Department of Chemistry, University of Oslo The data thus obtained will also be compared with results from an ongoing computational study on gas phase polymethylbenzenium reactivity. 6 papers presenting various studies are included. The titles are: 1) A Theoretical Investigation of the Methylation of Alkenes with Methanol over Acidic Zeolites. 2) A Theoretical Investigation of the Methylation of Alkenes with Methanol over Acidic Zeolites. 3) Theoretical Investigation of the Dimerization of Linear Alkenes Catalyzed by Acidic Zeolites. 4) Kinetic studies of zeolite-catalyzed methylation reactions. 5) Kinetic studies of zeolite catalyzed methylation reactions. 2. Coreaction of [''1''2C]propene or [''1''2C]n-butene and [''1''3C]methanol. 6) The intermediates in the methanol-to-hydrocarbons (MTH) reaction: A gas phase study of the reactivity of polymethylbenzenium cations.}
place = {Norway}
year = {2004}
month = {Jul}
}