Carbon monoxide oxidation oxygen concentration effect

CO, but it appeared that the oxygen could have changed the nature of the vessel surface, which was coated with boric acid. They finally concluded that the addition of CO, O2 or N2 had little effect on the initial oxidation rate. On the other hand, Hoare and Walsh [357] found an increase in the oxidation rate when the concentration of either the carbon monoxide or oxygen was raised. The contrasting results on the effect of oxygen are shown in Fig. 63 and 64. 

Mukesh, D., Cutlip, M.C., Goodman, M., Kenney, C.N., Morton, W., 1982. The stability and oscillations of carbon monoxide oxidation over platinum supported catalyst. Effect of butene. Chem. Eng. Sci. 37, 1807-1810. Mukesh, D., Kenney, C.N., Morton, W., 1983. Concentration oscillations of carbon monoxide, oxygen and 1-butene over a platinum supported catalyst. Chem. Eng. Sci. 38, 69-77. 

The precise technical name of HCN is Hydrocyanic Acid. The cyanides are true protoplasmic poisons, combining in the tissues with the enzymes associated with cellular oxidation. They thereby render the oxygen unavailable to the tissues, and cause death through asphyxia. Inhaling concentrations of more than 180 ppm of HCN will lead to unconsciousness in a matter of minutes, but the fatal effects would normally be caused by carbon monoxide poisoning after HCN has made the victim unconscious. Exposure to HCN concentrations of 100 to 200 ppm for periods of 30 to 60 minutes can also cause death. 

The effects of temperature and concentration on direct and indirect oxidation kinetics of carbon monoxide were correlated with global models. In 1986, Helling and Tester found the oxidation of carbon monoxide to be globally first order in carbon monoxide and independent of oxygen concentration over the range investigated. 

However, the removal of carbon monoxide by water-gas shift to a low level still demands its selective oxidation to the minimum concentration possible. Much research and development has been conducted during the past decades to find a gold catalyst that can do this the target is usually described by the acronym PROX (preferential oxidation), but sometimes as SCO (selective catalytic oxidation). The task is somewhat simplified by the constraints that are externally imposed the preferred feed gas, often termed idealised reformate, has the composition 1.0% CO, 1.0% 02, 75.0% H2, balance nitrogen or other inert gas, and while of course variations to this composition can be made to explore the kinetics and mechanism, and the effects of the products water and carbon dioxide can be added to observe their effects, the successful catalyst must remove almost all the carbon monoxide (to <10 ppm) and less than 0.5% hydrogen. This requirement is expressed as a selectivity based on the percentage of the oxygen consumed that is taken by the carbon monoxide this should exceed 50%, under conditions where the conversion of carbon monoxide is above 99.5%.5... 

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