George C. Hsu

Estimation of catalyst activity profiles in fixed bed reactors

The description of the steady state operation of a fixed bed catalytic reactor requires a certain amount of information about the catalyst activity distribution. For a monofunctional catalyst with no transport limitations the total catalyst activity is sufficient for describing the steady reactor operation. The total activity can be easily estimated from measurements at the reactor exit. In the presence of diffusional limitations, or in the case of bifunctional catalysts, the reactor description requires knowledge of the detailed activity profile. This can be approximately determined by parametrization and estimation of the parameters from a few measurements along the reactor. An application of the parametrization technique is made to a simplified model of naphtha reforming.

Estimation of Catalyst Deactivation Parameters from Operating Reactor Data

Techniques are presented for estimating the parameters of catalyst deactivation models from the operating data of industrial reactors. In the case of a first-order deactivation model, the partial differential equations describing the main reaction and deactivation are transformed to an ordinary differential equation for which estimation techniques are well established. The general power deactivation model can only be treated approximately and the case of a bifunctional catalyst must be treated by special methods. A numerical example is presented for the oxidation of butene to butadiene.