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Experimental and analytical investigations into the synthesis of the ceramic material based on the Ti–Al system with a nanodimensional porous structure are performed. The results of previous studies of the collective of authors show that it is reasonable to produce porous ceramic materials intended to filtrate liquids and gases in the thermal explosion mode (over the entire sample bulk) rather than by the layer-by-layer combustion. Nanoporous ceramic membranes are fabricated by self-propagating high-temperature synthesis (SHS) in one stage with the formation of the TiAl3 compound from a mixture of powders, wt %: 40Ti + 60Al. It is established that the synthesized material consists of the main TiAl3 phase with an insignificant amount of aluminum oxidized into Al2O3 and unreacted. Microstructural analysis of the sample fracture shows that the material has the developed surface and high open porosity. Its empirically determined magnitude reaches 48%, while the pore size ranges from 0.1 to 0.2 μm. The efficiency of fabricated porous material for the Ti–Al-based ceramic SHS filter reaches 99.999%, gas flow resistance is 100 mmHg, and filtration index is 0.062. The gas ultrafiltration capacity reaches 40 L(cm2 h) at a pressure drop across the filter of 2 kPa, while that of water ranges from 2 to 10 L/(cm2 h) at a pressure drop across the filter of 0.1 MPa. Membranes thus fabricated from ceramic materials with the gradient nanoporous structure can be used as filter elements for small installations providing fine water purification with the removal of bacteria, viruses, and dissolved organic carbon and for the fine purification of air and process gases with the removal of dispersed microimpurities and radioactive aerosols. The developed membrane SHS filters can be also demanded for installations operating in aggressive media and/or at high temperatures (up to 1000°C).

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.

The research is devoted to the development of scientific bases for creating a technology for manufacturing heat-resistant membranes based on a highly porous ceramic material with nanoscale pores (nanoporous), which allows increasing the efficiency of high-temperature purification of liquids from submicron dispersed contaminants by tangential filtration. Membranes based on a mixture of Ti and Al powders (40% by 60% mass ratio) were synthesized in one stage using the SHS method in the thermal explosion mode and used as filter elements in the ultrafiltration unit. Using X-ray and SEM methods, it was found that the synthesized material consists of the main phases TiAl3 and Al2O3. Analysis of the microstructure showed that the resulting ceramic material has a multilevel highly developed web-like nanostructure that forms an open porosity of the membrane, which provides the possibility of ultrafiltration.

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.