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Electron beam irradiation of Pd/Al 2 O 3 and Pd/C increased dispersion of Pd nanoparticles and activity in toluene hydrogenation by a factor 3-4.Nontraditional methods of catalyst activation (plasma treatment, microwave irradiation) attract significant attention of researchers working in the field of heterogeneous catalysis. Use of these non traditional methods allows obtaining of the new types of active sites on the catalyst surface possessing higher activity and/or selectivity.One of the promising methods is the irradiation catalysts by an electron beam [1 -3]. However, the literature data on studying an impact of the electron irradiation is scarce. The aim of this study consists in an evaluation of an impact electron beam on the structure and activity of Pd catalysts in toluene hydrogenation. 1%Pd/Al 2 O 3 catalyst was prepared using γ-Al 2 O 3 (BET surface area 120 m 2 /g). 1%Pd/C catalyst was prepared from carbon support «Sibunit» (BET surface area 330 m 2 /g). The catalysts were prepared by incipient wetness impregnation withThe activation of the catalysts by the electron beam irradiation was carried out using a LU-10-24 linear resonance electron accelerator in flowing air. The electron energy was 7.7 MeV. The irradiation dose was varied from 120 to 600 Mrad. The catalyst activity in the gas-phase toluene hydrogenation was evaluated using a flow type reactor operated at the atmospheric pressure at 100 -200 0 C. The analysis of the reaction products was performed by gas chromatography. Before catalytic runs the catalyst was reduced in the catalytic reactor at 250 0 C in the flowing hydrogen. Apparent activation energy of toluene hydrogenation was evaluated within a range of low toluene conversion (<15%).EXAFS measurements were carried out at HASYLAB (DESY, Hamburg) on the beam line X1 with the use of the double-crystal Si(311) monochromator. The EXAFS spectra were recorded in transmission mode in He flow at 80 K. Initial catalyst (before reduction) were studied. The catalysts after toluene hydrogenation were studied after the re-reduction in 5%vol H 2 in He in-situ special EXAFS cell at 250°C.Before spectra acquisition the samples were purged with He for 30 min in order to destroy Pd hydride formed in the course of the reductive treatment. The analysis of the EXAFS spectra was performed using the program VIPER for Windows [6]. The details of quantitative information extraction from EXAFS data and Pd particles size estimation are given in [7].The data on the impact of the electron irradiation on the catalytic activity of 1%Pd/Al 2 O 3 catalyst in the gas-phase toluene hydrogenation are given in Table 1. It is evident, that the catalyst activity is significantly improved with increasing irradiation dose from 10 to 600 Mrad. The toluene conversion at 200 °С increases from 32 % over parent catalyst to 58 and 100% with increasing electron irradiation dose to 240 and 600 Mrad respectively. Noteworthy that apparent activation energies of toluene hydrogenation for the parent catalyst and e-beam irradiated samples a...

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