Tsamopoulos J.A., Dandekar H.W., Scholtz J.H.
The channeling action of metal catalysts during graphite gasification is studied. A comprehensive model is developed using all available data in the literature. The dependence of the channeling velocity on the inverse of the particle diameter under oxidation over Pd is shown to be due to slower diffusion of carbon atoms through the catalyst bulk. On the other hand the proportionality of the channel propagation rate to the surface area of the particle available for reaction under hydrogenation over Ni is shown to be due to a slower surface reaction. In both cases increase of the channel depth retards the motion of the catalytic particle. © 1989.