Bildea S., Bozga Gr., Simulation of the gas-solid noncatalytic processes. Particle-pellet model. Revista de Chimie, 40(12), 1989 (in Romanian).

The paper analyses the nonisothermal unsteady particle-pellet model, demonstrating that the model is able to simulate a diversity of situations, from the chemical reaction control to the mass tranfer control. The model equations are discretized by orthogonal collocation and the resulting set of ODE is solved by a semi-implicit Runge-Kutta method. For certain values of model parameters multiple (unsteady) states are possible and the reaction system may follow an asymptotic or an oscillatory path.