CATALYST EFFECTIVENESS IN SULFUR-DIOXIDE OXIDATION

The sensitivity of the relationship between catalyst effectiveness in SO2 oxidation and the Thiele parameter to: (1) the kinetic expression with respect to the presence or absence of strong SO3 inhibition, (2) the activation energy in the range of 16-32 kcal/g mol, (3) the conversion of SO2 up to 90%, (4) the temperature at the exterior surface of the pellet in the range of 450-600°C, and (5) the feed composition ranging from 6-10% SO2 in air, was investigated. A nonisothermal model was used and the calculations were carried close to equilibrium. Far from equilibrium, the relationship is essentially unaffected except by conversion at the pellet surface for the case of strong product inhibition. Close to equilibrium, the relationship is significantly influenced by conversion, temperature, and the inlet composition but the form of the kinetics is not important. The activation energy is not a significant variable. Catalyst size, surface area, and density were not specified while it was necessary to fix the ratios of the transport properties for the calculations. The properties of the American Cyanamid V2O 5 catalyst were used for this purpose. © 1979.