Platinum Metals Rev., 1977, 21, (2), 42
Catalysts for Removing Oxygen from Stack Gases
A number of processes have been developed for the removal of air pollutants such as nitric oxide and sulphur dioxide from stack gases and one of these catalytically reduces the pollutants with carbon monoxide. Stack gases generally contain 1 to 3 per cent oxygen and there are a number of reasons why it is necessary to remove this prior to the gas entering the main catalytic reactor.
Ajay Sood, C. W. Quinlan and J. R. Kittrell of the University of Massachusetts have reported a comparison of the activities of several catalysts for the reduction of oxygen with carbon monoxide, both in the presence and in the absence of sulphur dioxide (Ind. Eng. Chem., Prod. Res. Dev., 1976, 15, (3), 176–179). Although initial testing of the catalysts was done using dry cylinder gas, three catalysts were also evaluated using wet flue gas.
The results demonstrated that in the presence of sulphur dioxide, of which 2500 ppm are typically present in stack gases, supported platinum and palladium catalysts were superior to the others tested. It is concluded that both alumina supported platinum and palladium have potential for the removal of oxygen from stack gases. The relative activity of these two was difficult to compare because of the experimental conditions; the platinum being supported on monolithic alumina while the palladium was on pellets.