The work described in this thesis involves the use of several techniques to investigate cyclopentene, cyclopentane and methylcyclopentane adsorption on metal surfaces. <SUP>2</SUP>D NMR spectroscopy was used to study the products of the exchange reaction of methylcyclopentane with deuterium over supported metal catalysts. The distribution and extent of exchange of deuterium in the hydrocarbon was found to vary with the metal used. <SUP>2</SUP>D NMR spectroscopy was used in conjunction with mass spectrometry to elucidate information on the intermediate species involved. Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and transmission infrared spectroscopy were employed to follow adsorption of cyclopentene, cyclopentane and methylcyclopentane on EuroPt-1 <i>in situ</i>. The behaviour observed using infrared spectroscopy was correlated with behaviour in the gas phase observed using mass spectrometry and thermal conductivity in the flow system used. This allowed quantification and analysis of the reactants and products. Molecular adsorption of the three molecules was observed, and temperature programmed desorption (TPD) was used to follow behaviour with increasing temperature. This allowed activation energy to desorption to be estimated. Cyclopentene showed complicated behaviour on heating, forming an unsaturated species on the surface. Cyclopentane and methylcyclopentane desorbed molecularly into the gas phase. Reflection Absorption Infrared Spectroscopy (RAIRS) was used to follow adsorption and TPD of the same hydrocarbon molecules onn a Pt(111) single crystal under UHV conditions. Adsorption was observed at low temperature, and multilayer build up of the three hydrocarbons was observed on increasing exposure.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:649609 |
| Date | January 1993 |
| Creators | Dolan, Anne S. |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/13677 |
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