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 SO2 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 O2, H2SO4, and SO2 indicated that surface diffusion was appreciable for SO2 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.