Sulfur dioxide oxidation in slurries of activated carbon. Part II. Mass transfer studies

Bubble‐to‐liquid, liquid‐to‐particle, and intraparticle mass transport effects were all found to be significant for some conditions in a three‐phase slurry reactor operated for the oxidation of SO 2 at 25°C and 1 atm. In particular, intraparticle diffusion was important for particles as small as 99 microns (effectiveness factor = 0.45). Effective diffusivities determined from reaction, desorption, and adsorption data for O 2 , H 2 SO 4 , and SO 2 indicated that surface diffusion was appreciable for SO 2 but not for oxygen. These results are consistent with the kinetic results in Part I which suggested that the rate‐controlling step was a chemisorption process for oxygen on the pore surface of the carbon particles.