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OP-II-11oxide support, it comes that the presence of Pt in the inlet zone of the catalyst, wherehigh oxygen partial pressures still exist, leads to an over-oxidation of the desiredproducts CO and H 2 . Based on the received data a new structured catalyst concept isproposed with a very low Pt concentration at the monolith inlet and successiveincrease along the flow direction. The intrinsic activity of the mixed oxide is exploitedfor the syngas formation at the monolith inlet with extensive presence of oxygen,while in the downstream section, once oxygen concentration is lowered, the rising Ptcontent in the catalyst favors at low oxygen pressure both the direct partial oxidationand the dry/steam reforming of remaining methane. The concept also results in afavorable heat management and reactor size, since the initial catalyst section withoutPt and lower catalyst activity is only slightly overheated, while the reforming sectionwith Pt can be shortened, as smaller quantities of CO 2 and H 2 O require reforming.On the basis of the presented concept, a new combination of active componentssupported on the single corundum monolith channel was prepared with Pt added tothe doped mixed oxide only partially, i.e. in the downstream segment. This newcatalyst was tested and compared to a system with homogeneous Pt concentration inthe monolith coating under the same CPOM conditions. Stability test with freshcatalysts revealed that channels without Pt in the inlet section stabilize much morerapidly than Pt gradient-free systems. Even after 26h on stream this latter system didnot reach steady state operation. It should be stressed, that yields of synthesis gasfor system with Pt gradient in the inlet part were higher then those for other systemwith homogeneous Pt distribution, i.e. overall larger quantity of supported Pt.In summary, the present work outlined a new concept for the effective distributionof the active component along single a channel monolith successfully tested for itsuse in catalytic partial oxidation of methane.References[1]. C.R.H. de Smet, M.H.J.M. de Croon, R.J. Berger, G.B. Marin, et al., AIChE J. 2000, 46, 1837-1849.[2]. D.A. Hickman, L.D. Schmidt, AIChE J. 1993, 39, 1164-1177.[3]. V. Sadykov, S. Pavlova, et al., Kinetics and Catalysis 2005, 46, 227-250.[4]. T.G. Kuznetsova, V.A. Sadykov, et al., Stud. Surf. Sci. Catal. 2002, 143, 659-667.AcknowledgementsThis work was carried out in frames of Russian-French Associated European laboratory oncatalysis and supported by RFBR–CNRS 09-03-93112 Project.119