Model studies, sulfur dioxide oxidation

Cerium-zirconium mixed metal oxides are used in conjunction with platinum group metals to reduce and eliminate pollutants in automotive emissions control catalyst systems. The ceria-zirconia promoter materials regulate the partial pressure of oxygen near the catalyst surface, thereby facilitating catalytic oxidation and reduction of gas phase pollutants. However, ceria-zirconia is particularly susceptible to chemical and physical deactivation through sulfur dioxide adsorption. The interaction of sulfur dioxide with ceria-zirconia model catalysts has been studied with Auger spectroscopy to develop fundamental information regarding the sulfur dioxide deactivation mechanism. 

Thus, the ln(C /C o) varies linearly with position z. This suggests studying experimental reactors of different length (fixed Vq ) or varying Vq (fixed z). Baron et al. (1952) used this model to study oxidation of sulfur dioxide on a vanadium pentoxide catalyst. 

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