Catalytic oxidation of hydrogen over Au/TiO2 catalysts

Selective catalytic oxidation of hydrogen in the presence of hydrocarbons was studied in a fixed bed quartz reactor, over 3 wt%Au/TiO2 and 5 wt%Au/TiO2 catalysts. This reaction can be utilised in the production of light alkenes via catalytic dehydrogenation, providing in situ heat to the endothermic dehydrogenation reaction and simultaneously removing a fraction of the produced hydrogen. It is important to avoid the non-selective combustion of the hydrocarbons in the mixture. Both 3 wt%Au/TiO2 and 5 wt%Au/TiO2 are active for the combustion of hydrogen, but in a gas mixture with propane and oxygen the selectivity is dependent upon the feed ratio of hydrogen and oxygen. At 550 degrees C, with propane present, no carbon oxides are formed when the H-2:O-2 ratio is four, but at lower ratios some CO2 and some CO is formed.