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A porous catalytically active membrane based on α-Al2O3 was synthesized. Powdered additives of the eutectic composition of magnesium oxide and silicon carbide were added to the initial corundum filler to synthesize a membrane framework with high open porosity and physical and mechanical characteristics that was pressed at 40 – 70 MPa followed by sintering in process combustion mode. Additives of Re2O7 andWO2 were added up to 4 mass% to the initial mixture by a simple technological method to impart catalytic properties to the synthesized membrane. Scientific foundations were developed for creating a technology for one-stage production of catalytically active ultraporous membrane converters effective for dehydrogenation of cumene to α-methylstyrene.

A porous, catalytically active membrane based on coarse-fraction silicon carbide was synthesized. Ultrafine additives with an eutectic composition of magnesium oxide and silicon carbide, which during sintering at temperatures from 1100 to 1450°C form a liquid phase in the form of clinoenstatite MgSiO3 that wets the coarse-size SiC particles and forms a strong porous framework of the membrane, were introduced into the initial SiC powder to synthesize the membranes. The pore size of the ceramic material was studied as a function of the pressing pressure, which made it possible to obtain a highly porous ceramic membrane with pore size optimized for dehydrogenation of ethylbenzene into styrene. Modification of the pore surfaces to 10% Re – W by means of active components using the alkoxy method is performed in order to give the synthesized membrane the catalytic properties required for realizing the dehydrogenation process.

Propylene and butadiene considered as the most popular raw materials in the modern industry of basic organic and petrochemical synthesis with a continuing tendency to increase demand for their consumption.

The work is devoted to the preparation of catalytically active membranes for the dehydrogenation of ethylbenzene to produce styrene which is necessary for the synthesis of numerous types of polymers, for example, polystyrene, styrene-modified polyesters, ABS (acrylonitrile-butadiene-styrene), and SAN (styrene-acrylonitrile) plastics. The global production of styrene in 2018 amounted to ~ 30 million tons, with up to 90% of styrene obtained by dehydrogenation of ethylbenzene in the presence of water vapor.