CHARACTERIZATION OF MULTICOMPONENT DIFFUSION EFFECTS IN MTBE SYNTHESIS

The application of multicomponent diffusion theory to characterize intracatalyst mass-transfer resistances in the liquid-phase synthesis of methyl tert-butyl ether using acidic ion exchange resins is discussed. By formulation of invariant solutions to the multicomponent conservation equations, the system of coupled differential equations is reduced to a single ordinary differential equation and solved using orthogonal collocation. The parameters characterizing the invariant solutions are shown to yield significant, insight into the nature of the diffusion processes and illustrate the importance of accounting for multicomponent diffusion effects. A comparison between model predictions and published experimental data indicates good agreement between model and experiment in the limit where diffusion of methanol is rate limiting.