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Operation in corrosive media and/or at high temperatures requires improved characteristics of the performance and durability of filtering equipment. The Ti – Al intermetallic system combines low density with high strength and exhibits high resistance to oxidation and corrosion at elevated temperatures. We present the results of studying high-temperature Ti – Al cermet products (filters) with nanoscale pores. Filters were obtained from a mixture of Ti and Al powders (mass ratio 40:60) by thermal explosion. XRD methods showed that the synthesized material consists of two main phases: TiAl3 and Al2O3. The microstructure analysis revealed the presence of large-sized TiAl3 structures and spherical Al2O3 aggregates enveloped by nanostructured TiAl3. Moreover, nanoscale fibrous TiAl3 compounds forming a multilevel developed cobweb-like structure are observed in the entire volume of the pore space of the material. The open porosity of the material was 48%, the pore size was 0.1 – 0.2 μm, the efficiency of the porous material was 99.999%, the resistance to gas flow was 100 mm of water column, and the filtration index was 0.062. Thermal tests revealed the possibility of effective use of filters under conditions of elevated (up to 800°C) temperatures and corrosive media due to the chemically stable and heat-resistant binary structure of the material. The results obtained can be used to improve the methodology of the development and operation of high-temperature cermet filters based on Ti – Al.

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.

The possibilities of combined piercing through and “blind” holes in hard-to-process materials are considered. The possibilities of intensifying the processing process by using multi-electrode tools are presented. A fundamentally new element of the new technology is the creation and use of a new working environment based on a rheological fluid with variable viscosity. This determines the conditions for mass removal of processing products from the hole forming site and creates conditions for process stabilization. The method is protected by a Russian patent and has been used in many factories countries. The article considers the technology of processing parts in the proposed working environment, which implements the proposed method in the form of a technological process in the manufacture of parts with holes of different cross-sections. At the same time, the use of combined multi-electrode cross-linking allowed up to 3 times to speed up the production of channels for cooling parts of the hot zone of thermal machines, and to achieve stability of cross-section sizes within ±5%. This technology expands the use of electrical processing methods in General and special engineering in the manufacture of parts from hard-to-process alloys.

Conductance of thin semicontinuous metallic films is measured in coplanar waveguide configuration at frequencies of 1 GHz to 20 GHz. The presented model of the microwave network correlates the experimental scattering parameters (S11) and (S21) with complex impedance and propagation constant, from which we are able to determine the films surface conductance, coefficients of reflectance, transmittance and dissipation. The measurement is illustrated on films of gold, 4 nm to 12 nm thick. After percolation from individual nanoparticles, films thicker than 10 nm resemble a continuous conductor. The presented methodology accurately captures the insulator to conductor transition, and can be used to determine microwave characteristics of such materials.

Internal photoemission (IPE) spectroscopy is a powerful technique for investigating electronic properties of inhomogeneous interfaces of hetero‐structures. Two of the most important aspects of IPE measurements involve threshold spectroscopy and photoelectron yield spectroscopy. In the first measurement type, IPE is used to determine the barrier heights at the interfaces while the second deals with photoemission of carriers (electrons and holes) with the energies above and below the barrier. We will present a brief description of the IPE principle upon which the extraction of the interfacial energy thresholds or barrier heights is based. The details of our IPE experiment setup will be also presented. For applications, in this report we will focus mainly on the first aspect of IPE where we determine the barrier heights of a technologically important class of materials which includes various metal‐high‐k insulator‐semiconductor structures.