The chemistry of butane has been studied over two well characterised catalysts, EuroPt-1 doped with potassium hydroxide to 1% weight in potassium. The exchange of butane with deuterium produced a U shaped distribution of deuterated products, with maxima at the singly exchanged and fully exchanged butanes over both catalysts. The rate of exchange over the 1% potassium doped catalyst was nearly two orders of magnitude lower than over EuroPt-1. The application of Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) to strongly infrared absorbing catalytic systems was discussed, with the inherent advantages and disadvantages of the technique. It was concluded that it was a useful method for studying the region of the infrared spectrum associated with carbon-hydrogen stretching vibrations, but the strong absorbance of the catalysts' silica support made study of the carbon-hydrogen deformation region difficult for both EuroPt-1 catalysts. The adsorption of butane on EuroPt-1 and 1% potassium doped EuroPt-1 in a flow system was studied using DRIFTS at 298 K and 378 K. The chemistry was similar over the two catalysts, but all infrared intensities were signficantly lower over the 1% potassium doped catalyst. In comparison with equivalent single crystal studies, the main species present at 298 K was assigned to a di-σ or di-σ/π adsorbed butane. Heating preadsorbed butane to 378 K, or adsorbing butane at 378 K produced an infrared spectrum assigned to butylidyne. Further heating evolved hydrocarbon as methane. The reaction of the adsorbed species with pulses of hydrogen was also studied.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:652523 |
| Date | January 1992 |
| Creators | Holmes, Philip D. |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/14090 |
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