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Ceramic and cermet membranes containing catalytic coatings in the internal volume of their channels were obtained. A relationship between the permeability and kinetic regularities of CO oxidation describing the transmembrane flow of gases was studied. The pre exponential factor and apparent activation energy change as the loading of the membrane channels by the catalyst proceeds. The study of gas permeability through the membranes showed that the catalyst with a loose branched surface is distributed in the membrane microchannels. The reaction rate constant increases in parallel with an increase in the relative fraction of the catalyst surface. The CO oxidation rate is assumed to depend statistically on the number of active sites, which increases with filling of the membrane channels by the catalytic material.Regularities of heterogeneous catalytic reactions in channels of ceramic and cermet membranes are of great interest for researchers in the area of continuously devel oping nanotechnology. In the general case, gas transfer in porous media occurs due to viscous, slipping, surface, and molecular flows. 1,2 Since catalytic coatings with large specific surface have high ratios of the catalytic coating surface to the volume of transport pores of a microreactor (S/V), it can be expected that the frequency of interaction of molecules with walls of the pores increases in these systems, and catalytic reactions occur therein more in tensely than in macroreactors.Alkoxo methods forming oxide catalytic systems from colloidal solutions of metal complex precursors can be considered as promising for designing catalytic oxide coat ings in channels of ceramic membranes. 3,4It has previously 5,6 been shown that a number of ox ides containing transition metal ions and obtained by the alkoxo method exhibit high activity in the low tempera ture oxidation of CO.In this work, we present the results of studying the kinetic regularities of CO oxidation with air when the gas is transferred through channels of cermet and ce ramic membranes, whose internal walls are modified by single phase oxide systems Cu 0.03 Ti 0.98 O 2±δ of anatase structure and 0.06NiO•0.94Al 2 O 3 of spinel structure. These oxides can be used as active catalytic systems in CO oxidation when applied as powders and coatings on mono liths. 4,6-8 . ExperimentalCermet (Trumem ТМ ) and ceramic (BUM) microporous membranes as tubes with a diameter of 14 mm and disks with a diameter of 40 mm were used. 9,10 The cermet membrane has a bilayer composite structure consisting of a support and sup ported rutile layer. The support is based on the SS316L porous stainless steel. Its thickness is 200 µm, the average pore volume is 2 µm, and the estimated specific surface is 1.5•10 4 cm 2 cm -3 . A thin ceramic rutile layer is 20 µm thick, its average pore volume is 0.13 µm, the estimated specific surface of the ceramic layer is 2•10 5 cm 2 cm -3 , the porosity is 30-35%, and the air permeability is 330-400 m 3 h -1 m -2 atm -1 .The BUM ceramic membrane is based on titanium carbide a...

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