III International Conference

PP-I-45STUDY OF AN INFLUENCE OF PREPARATION CONDITIONS OF ALUMINASUPPORTED URANIUM OXIDE CATALYSTS ON THEIR CATALYTIC ANDPHYSICO-CHEMICAL PROPERTIESShikina N.V., Ismagilov Z.R., Kuntsevich S.V., Rogov V.A., Ushakov V.A., Boronin A.I.,Zaikovskii V.I., Kuznetsov V.V., Lazarchuk V.V. 1 , Balakhonov V.G. 1 , Matyuha V.A. 1 ,Drobyaz A.I. 2 , Khlytin A.L. 2Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia1 Siberian Chemical Complex, Seversk, Russia2 Plant of Chemical Concentrates, Novosibirsk, RussiaE-mail: shikina@catalysis.ruThree series of the 5%U-Al 2 O 3 catalyst were prepared by impregnation, solid phasesynthesis and mechanical blending methods. The catalysts were studied by S BET , XRD, TPR,SEM, TEM and XPS. It has been shown that properties of the catalysts prepared by varioustechniques depend on a synthesis method and are caused by different degree of interaction ofactive component and support. A mixture of UO x and AlO x is presumably responsible forcatalytic activity at low temperature. This phase is not identified precisely so far. The catalystcalcined at temperature around 1000 ºC has finely (0.1 nm) dispersed active componentconsisting of nanosized uranium oxide.Uranium oxides possess unique properties, they are new generation of catalytic materials andthere is great potential to various catalytic processes. The continues series of oxygen containingcompounds, which are characterized by different O/U ratio and include uranium in valence statefrom 4 to 6, are most interesting for catalysis. High activity of uranium oxide catalysts has beendiscussed in the literature. Supporting of uranium oxides allows reducing the total amount ofuranium in a catalyst and increasing thermal stability of a catalyst and its lifetime [1, 2].Uranium oxides are known to form complex oxides, such as uranates and polyuranates,with alkali, alkali-earth, rare-earth and transition elements. There are restricted data onformation of mixed uranium oxides with alumina, which is usually used as a catalyst support.Even in the X-ray database JCPDS the system U-Al-O is not described.The objective of this paper is preparation and study of catalytic activity of nanosizeduranium oxides supported on alumina depending on preparation conditions and hightemperature treatment.Three series of the 5%U-Al 2 O 3 catalyst were prepared by impregnation of γ-Al 2 O 3 withaqueous solution of uranyl nitrate (UO 2 (NO 3 ) 2 ⋅6H 2 O), solid phase synthesis and mechanicalblending. Synthesized catalysts were calcined at 500, 600, 800, 900, 1000 ºС and studied by89