Abstract. Pd/H-Beta catalysts with different silica-to-alumina ratio prepared by an impregnation method have been studied by XANES/EXAFS, IR, XRD and TEM. It was shown that palladium in calcined Pd/H-Beta samples exists as palladium oxide that can be easily reduced to Pd metal. The catalysts were tested in selective oxidation of piperonyl alcohol to piperonylaldehyde at 80 oC. The Pd/H-Beta…