The catalytically active coatings of tube wall reactors, consisting of an aluminium oxide washcoat and platinum, platinum/tin, or platinum/rhenium deposited by incipient wetness impregnation, are characterized using BET surface area measurements, CO chemisorption, X-ray photoelectron spectroscopy, plasma atomic emission spectroscopy, high resolution transmission electron microscopy (HRTEM), and extended X-ray absorption fine structure analysis (EXAFS). The mesoporous catalysts show a type-IV adsorption isotherm, yielding an average pore diameter of 9 mm, and a BET surface area between 178 and 197 m(2)/g. From the bulk and surface analysis results, an enrichment of tin or rhenium, respectively, is found to take place at the surface of the bimetallic catalysts. Very good agreement between the particle sizes estimated from EXAFS, CO-chemisorption, and HRTEM data is found for a low loading (1.5 wt%) platinum catalyst, leading to dispersion values between 75 and 80%, a cluster size of 30 atoms, and a particle diameter around 13 Angstrom. Using the catalytic dehydrogenation of methylcyclohexane as a test reaction, it is demonstrated that a pretreatment at high reduction temperatures leads to a decrease in activity. EXAFS show that this effect is due to a stronger metal-support interaction, as indicated by the appearance of a Pt-O contribution at 2.25 Angstrom in the coordination sphere of the surface platinum atoms.