A two-phase compartments model for the selective oxidation of n-butane in a circulating fluidized bed reactor

A phenomenological model for the partial oxidation of n-butane to maleic an hydride (MAN) in a gas-solid riser reactor is proposed. The model captures the main transport-kinetic interactions at both the particle and reactor sc ale. Two different kinetic models from the literature that either include o r neglect the role of solid-state diffusion of oxygen in the catalyst bulk are compared in terms of their impact on overall reactor performance. The u se of computational fluid dynamics (CFD) as a means of defining a macroscop ic cell-type model for describing the flow patterns in an industrial-scale gas-solids riser is also described. Predictions for the conversion of n-but ane and yield of MAN are presented as a function of selected operating vari ables, and the impact of the variable model parameters on the predictions i s briefly assessed. It is shown that the predictions are particularly sensi tive to the kinetic model. The relative importance of the interactions betw een the chemical kinetics and the hydrodynamics is also highlighted. (C) 20 00 Published by Elsevier Science B.V.