Progress in catalyst development for reactions such as Fischer-Tropsch synthesis (FTS) has been impeded by the time consuming characterisation and catalytic testing of new formulations. Hence, this thesis discusses the development of high-throughput (HT) techniques for studying the deactivation of cobalt based catalysts under simulated FTS conditions. Libraries were rapidly synthesised by incipient wetness methods utilising robotic platforms and then treated in arrays under conditions designed to cause rapid ageing. HT X-ray diffraction (XRD) was performed before and after the ageing test to monitor the deactivation of the catalysts by sintering of the active metal particles or loss of metallic cobalt. HT thermogravimetric analysis in 5 % H2 was utilised to probe the reducibility of the catalysts and this information was then combined with results from XRD to inform decisions on which formulations to scale-up for further testing. This approach led to the discovery of highly stable Co/Ru/Mg/γ-Al2O3 catalysts. Thorough characterisation of selected hits was carried out to understand the phase assemblage. In addition to the high stability of Co/Ru/Mg/γ-Al2O3 catalysts, there was also a lowering of intrinsic activity. The degree to which the intrinsic activity was decreased was dependent on the amount of Mg in the catalyst and more specifically, the amount of Mg in close proximity to Co as identified by the amount of Mg incorporated into MgxCo3-xO4 phases prior to activation. In addition to incipient wetness synthesis, a method was also developed to perform HT co-precipitation synthesis with the aid of robotic platforms. HT synthesis was coupled with HT XRD to determine synthesis conditions giving rise to high surface area, phase-pure magnesium aluminate supports.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:579378 |
| Date | January 2013 |
| Creators | Gallagher, James R. |
| Contributors | Rosseinsky, Matthew J.; Claridge, John B. |
| Publisher | University of Liverpool |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://livrepository.liverpool.ac.uk/10793/ |
Page generated in 0.0012 seconds