Transport modelling of packed-tube reactors - IV: Steady-state modelling with intraparticle gradients

A data-based model of surface states in packed tubes is joined with an intr aparticle diffusion-reaction model to describe reactors with significant in traparticle gradients. This modelling approach is demonstrated with steady- state simulations of the partial oxidation of n-butane to maleic anhydride in a packed-tube reactor with spherical particles and a tube/particle diame ter ratio of 2.02. The simulation is based on a correlation of heat transpo rt experiments performed in a unique packed-tube gas flow apparatus, and on a kinetic model taken from the literature. An orthogonal collocation schem e, using rounded Hahn polynomial zeros as axial nodes and Jacobi zeros as i ntraparticle nodes, allows efficient solution of the resulting detailed rea ctor model. (C) 2000 Elsevier Science Ltd. All rights reserved.