THE FORMATION OF SO3 IN A FLUIDIZED-BED

The oxidation of SO//2 to SO//3 in an electrically heated bed of sand fluidized by mixtures of N//2, O//2, H//2O, and SO//2 has been studied from 973 to 1223 K at atmospheric pressure. The amounts of SO//3 formed were much less than those for equilibrium. The results suggest that the oxidation is a heterogeneous catalytic reaction on the surface of the sand. A simple Eley-Rideal mechanism is propose, in which O//2 and SO//2 competitively chemisorb on the sand, with the rate controlled by gas-phase SO//2 reacting with adsorbed O atoms.