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A kinetic study into the styrene hydrogenation over a palladium on alumina catalyst has been made. Styrene was used as a model component for pyrolysis gasoline. A kinetic rate expression has been derived and the inhibiting e ect of sulfur components has been included. Using this kinetics and mass-transfer models compiled from literature, the performance of two types of reactors for the styrene (pyrolysis gasoline) hydrogenation has been evaluated. A structured reactor such as a monolith has large advantages over a conventional trickle-bed reactor. For the monolithic reactor a more than 3 times higher volumetric productivity is obtained with much less catalyst. The modeling results indicate that deactivation by gum formation should be signiÿcantly less due to much better hydrogen mass transfer in the reactor. ?

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A rapid, simple, and efficient method for the preparation of highly dispersed supported Au catalysts has been developed. In the preparation, NaBH4 is used to reduce the Au precursor, lysine is employed to cap the formed Au colloids, and a short sonication time is applied to facilitate dispersion and deposition of the Au colloids onto the catalyst support, which has been mixed with the precursor beforehand. The end‐point pH value of the solution and the isoelectric points (IEPs) of the catalyst supports have an influence on the size of the Au particles and their deposition. The optimum value for the end‐point pH is 7.5–10.0, and the IEP should be 5–10. The amino acid capping agent is easily removed at the catalyst activation stage at 200 °C, and the Au particles are thermally stable against sintering, even at 500 °C for 3 h. It is also proven that the method is applicable to the preparation of supported Pt catalysts. The catalytic activity of the prepared Au catalysts for CO oxidation in the absence/presence of H2 is comparable to that of a Au catalyst prepared by the co‐precipitation (CP) method, and to that of the standard catalyst from the World Gold Council (WGC). X‐ray photoelectron spectroscopy (XPS) results show that only metallic Au exists in the catalysts before and after activation, and also after the catalysis reaction.

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