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OP-I-17KINETICS PARTICULARITIES OF PHENOL HYDROGENATION OVERPd IMPREGNATED HYPERCROSSLINKED POLYSTYRENESulman E. 1 , Chernyavsky V. 2 , Ivanov A. 2 , Sulman M. 1 ,Matveeva V. 1 , Kharitonov A. 21 Tver State Technical University, Institute of Nano and Biotechnologies, Tver,Nab. A. Nikitina 22, sulamn@online.tver.ru2 Boreskov Institute of Catalysis, Novosibirsk, Russia, khar@catalysis.ruPhenol hydrogenation over Pd based catalysts is widely used in industry forcyclohexanone synthesis in caprolactam production. The main reaction products arecyclohexanone and cyclohexanol. Process engineers try to obtain the maximalphenol selectivity for cyclohexanone at full phenol conversion. The use of Pdhypercrosslinked polystyrene catalyst can be an essential step toward this goal.In the literature, phenol hydrogenation is considered as a two-route reaction withsuccessive conversion of phenol to cyclohexanone according to the scheme:1) C 6 H 5 OH + 2H 2 = C 6 H 10 O2) C 6 H 10 O + H 2 = C 6 H 11 OHThe reaction is assumed to proceed by the Langmuir–Hinshelwood mechanism.To refine the route scheme for a new catalyst, we studied the kinetic regularitiesunder wide variation of phenol conversion in a steel isothermal flow reactor over thetemperature range of 120 to 181°C. The inlet concentrations were 11% for phenoland 80% for hydrogen. The 0.5 g catalyst sample was diluted with quartz grains inthe ratio of 1 to 3. The bed height was 23 cm. The catalyst was prepared byimpregnating the spherical particles of hypercrosslinked polystyrene with a solution ofNa 2 PdCl 4 . The content of palladium in the catalyst was 0.5 wt %. Active metalnanoparticles were mainly distributed nearby the outside surface of polymergranules, the thickness of saturated layer was found to be 0.04 mm. The catalyst wascharacterized by XPS, XFA, nitrogen physosorption, transmition electron microscopyand FTIR CO. Figure 1 shows selectivity for cyclohexanone versus phenolconversion at different temperatures. The dependences indicate that the minimumnumber of routes is three. Along with the above mentioned routes, there is anadditional route of cyclohexanol formation:3) C 6 H 5 OH + 3H 2 = C 6 H 11 OH68