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OP-II-17CATALYTIC COATING OF METALLIC SUBSTRATES ANDAPPLICATIONS TO INSERTS AND CATALYTIC REACTORSLöfberg A. 1 , Essakhi A. 1 , Swesi Y. 2 , Meille V. 2 , Pitault I. 2 , Paul S. 1 ,Supiot P. 3 , Mutel B. 3 , Le Courtois V. 1 , Bordes-Richard E. 11 Unite de Catalyse et de Chimie du Solide, UMR CNRS 8181, Universite Lille 1,Villeneuve d’Ascq, France, Axel.Lofberg@univ-lille1.fr2 Laboratoire de genie des procedes Catalytiques, UMR CNRS 2214, CPE-Lyon,Villeurbanne, France3 IEMN -UMR CNRS 8520, Universite Lille 1, Villeneuve d’Ascq, FranceCatalytic micro(milli)reactors or structured reactors offer a potential to conductmass or heat transfer-demanding reactions under safe conditions while maintainingand/or increasing selectivity and productivity. Whatever the size and the design of thereactor the key material is the catalytic active phase which must be deposited as thinlayers onto the metallic inserts or reactor walls of reactor. This assembly must bemechanically and thermally stable, and chemically resistant. Moreover the activephase must retain its own surface area, porosity, and activity, selectivity.We have investigated the parameters leading to successful coating by oxides thatbear no chemical resemblance with the metallic substrate. Stainless steel (SS) orFeCrAlloy 5×2×0.05 (mm) plates (to figure out reactor walls) and foams (Porvair®,various ppi) as inserts were used as substrates. Two model reactions were studied.One was the oxidative dehydrogenation of propane on 7%VO x supported on TiO 2 [1],the other was the dehydrogenation of methylcyclohexane (MCH) on a supportedmetal, 2%Pt/Al 2 O 3 [2]. Several methods of coating were used after cleaning andappropriate pretreatments of plates/foams, from dip-coating in suspension withcontrol of the rheology for TiO 2 and alumina supports [3], to grafting by alcoolates(VO x polyvanadates) or impregnation (H 2 PtCl 6 ) followed by calcination or in situ heattreatment, respectively, to get the active phase. In a former work on 7%VO x /TiO 2 /SSplates, Fe was shown to diffuse outwards and to poison vanadium leading todecrease of the selectivity to propene in the ODH of propane [1]. To avoid that, aprimer consisting of a micron-thick silica-like layer intended to act as a barrier wasdeposited onto the metal by RPECVD (Remote Plasma Enhanced Chemical VaporDeposition). This method was successful for coating cobalt on silica support ontostainless-steel plates for Fisher-Tropsch reaction [4]. The technology was adapted tothe coating of foams by using a specially designed sample holder [5]. Figure 1 showsthe layers of TiO 2 /SiO 2 on a branch of foam and on the surface of a plate analysed byElectron Probe Micro Analysis.130