Objective To develop improvements to be made to gas detection systems.Results showed that tin (iv) oxide was readily deposited on the coils to procure a thick monolithic coating. After coating with palladium, the resulting bead readily oxidised carbon monoxide and hydrogen and, to a lesser degree, butane. Little catalytic activity was shown in the presence of methane and further work is clearly necessary before a device suitable for trials in an industrial environment could be developed.Apart from the sudden deterioration in performance of gas detectors due to the presence of poisons, many problems may arise due to the construction and manufacture of such devices.In practice, catalytic sensors lose activity after prolonged use at high temperatures or after operation in gas rich atmospheres and this may be due to agglomeration of the crystallites of the active component or to breakdown the refractory support caused either by its inherent chemical instability or by the effects of thermal shock. The latter mode of deactivation is helped by the fact that, using conventional methods of deposition of the refractory metal oxide which involve the thermal decomposition of a water-soluble precursor of that oxide, a poor bond is formed between the metal base and the oxide. It is possible to manufacture a gas detector which displays suitable mechanical strength and resistance to thermal effects by means of chemical vapour deposition of a suitable oxide.As a result of the present work, it appeared that, although little could be done to prevent the initial interaction of the inhibitor and the catalyst, certain catalyst-support systems recovered very much more rapidly than others from this interaction. One such system was based on tin (iv) oxide.In an attempt to exploit the ability of tin (iv) oxide to recover from exposure to poisons and incorporate the stability of vapour deposited oxides, preliminary experiments were carried out with a palladium-tin oxide sensor produced by cvd. The device was of similar construction to a pallistor detector and consisted of a helicat platinium coil embedded in a bead of tin (iv) oxide. The bead was produced by the vapour phase oxidation of tin (iv) chloride on the heated metal coil and the palladium was applied from a solution containing a suitable salt. Programme(s) ENG-HYDROCARB 1C - Programme (EEC) of Community projects in the hydrocarbons sector, 1973-1985 Topic(s) 1.9 - PRODUCTION SYSTEMS Call for proposal Data not available Funding Scheme DEM - Demonstration contracts Coordinator Sieger Ltd EU contribution No data Address Hatch Pond House 4 Stinsford Road Nuffield Estate BH17 7RZ Poole United Kingdom See on map Total cost No data
