Abstract
This thesis comprises analysis for two types of catalysis: CO oxidation and N2O decomposition; related by their research in sol-gel catalysis. The CO oxidation work was undertaken on behalf of Servomex plc in order to understand how their catalyst-based sensor (Tfx 1750) worked and why it failed when exposed to coal power station flue streams within its two-year guarantee period. This research will show, by means of many analytical techniques and catalytic tests: 1. A comparison of the Servomex catalyst powder and a sol-gel prepared material containing the same components: 10 % Pt on 10 % Zr02 doped Al2O3. 2. The mechanism of CO oxidation observed on the surface of these catalysts. 3. What effect sulphur oxides (SO2 and SO3) have on both catalysts, and the mechanisms that give rise to S build up on their surfaces. In contrast, the catalysed N2O decomposition research was sponsored by Dytech in order to determine which metal oxides and multimetal oxide systems are suitable for N2O decomposition in satellite propulsion systems. This research will allow: 1. A comparison of a wide range of metal oxide systems during thermal treatment in an N2O atmosphere. 2. Further analysis into the best systems with respect to their suitability as catalysts; such as selectivity, activation temperatures, longevity and reliability. 3. A comparison of different preparation techniques; precipitation and sol-gel, by using various analytical techniques and catalytic testing. 4. A comparison of the in-house rig system designed for the comparison of catalysts by thermal treatment, and a rig system built by the Surrey Space Group as a realistic comparison for actual satellite propulsion systems. This comparison will justify the results shown in part (1).