Numerical exploration of diffusion-controlled solid-state reactions in cubic particles

The characteristics of diffusion-controlled solid-state reactions in cubic particles are explored in this study. In order to capture the three-dimensional reaction front, the diffusion equation, subject to an interfacial chemical reaction in cubic particles, is solved in a transient form using the finite volume method. How the unreacted core is shrunk with time is clearly revealed. In addition, the concentration distributions of reactants and products are numerically predicted. A comparison of reacted zones advancing along different directions from the particle surface to the center is also made. The simulated kinetic curves at different conversion constants are shown to be useful to evaluate the conversion kinetics of diffusion-controlled solid-state reactions in cubic particles. (C) 2003 Elsevier B.V. All rights reserved.