The kinetics of the hydrogenation of gas mixtures of ethyne and ethene on a commercial Pd catalyst was studied experimentally using a Berty reactor. The experimental conditions corresponded with typical industrial tail-end conditions, 0.3-1.3% C2H2, 0.4&4% HZ, the balance being ethene. The influence of small amounts of carbon monoxide added to the feed gas was also investigated. The pressure was varied between 0.3 and 2.1 MPa and the temperature between 299 and 330 K. The maximum temperature was limited due to mechanical problems of the Berty reactor. Eight different sets of rate expressions, partially adapted from expressions previously proposed in the literature, have been tested. No ' best' model was chosen, because many models were found to describe the data equally well. The prediction of the rate of ethane formation was less accurate than the prediction of the rate of cthyne hydrogenation.This was not only due to the higher experimental error involved, but also because ethane could be formed by alternative routes. In deriving adequate rate expressions for the rather complex system, a compromise has to be sought between the relative inaccuracy of the simpler expressions and the inability of determining the large number of parameters in more complex expressions.

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This work describes a novel method that enables the calculation of a series of adsorption isotherms basically from a single Temperature-Programmed Desorption (TPD) experiment. The basic idea is to saturate an adsorbent packed in a fixed bed at a certain feed concentration and temperature and to subsequently increase its temperature linearly with time, while maintaining a constant feed concentration. We measured TPD response curves for carbon dioxide on activated carbon at different heating rates for various combinations of feed concentration, molar flow rate and particle size. Response curves from an axially dispersed plug flow model were fitted to experimental data by adjustment of the Langmuir parameters. Adsorption isotherms calculated with these fitted parameters are in good agreement with adsorption data obtained by other methods over the full temperature range. The influence of heating rate on intraparticle mass transfer resistance is discussed.

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