Remember from elementary chemical thermodynamics that, for exothermic reactions (such as sulfur dioxide oxidation), an increase in temperature decreases the equilibrium conversion. Converse is of course the case for endothermic reactions: an increase in temeperature increases the equilibrium conversion.
Analysis of the effect of total pressure P on equilibrium conversion ((ySO2,in - ySO2,eq)/ySO2,in) is illustrated by the following equation (with the assumption that all solid phases have unit activity):
Make sure you know how to solve Problem 5.19 in Benítez, which is typical for the kinetics of 1st-order "calcination" (thermal decomposition) reactions.
lrr3@psu.edu (revised 11/03/98)