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The studies were performed suggesting that the cause of P2O5 losses during apatite-staffelite ores (ASO) treatment are due to non-selective flocculation of fine classes during flotation. When using strong flocculants, special preparation of condensed slurries is necessary, ensuring their deflocculation before the flotation process. A scheme and mode of preparation of fine classes for the flotation process have been developed, including thickening of the classification overflows using strong anionic flocculants and deflocculation of the thickened product before the flotation process with reagents-dispersants used in the basic flotation mode. A mode of preparation of slimes of ASO ores for flotation is proposed, including thickening of the discharge of the classification operation using the anionic flocculant “Praestol-2540”, conditioning of the condensed product with additions of liquid glass and caustic soda in a ratio of 1 : 1, dilution and re-thickening of deflocculated slimes, consolidation and flotation thickened sludge and sand. The big laboratory tests have shown that the application of the developed regime provides a total increase in the extraction of P2O5 from ore from 70,1 to 71,5 % with an increase in the P2O5 content in apatite concentrate from 37,1 to 37,8 %, which makes the developed technology promising for processing refractory ASO at Kovdorsky GOK.

The article discusses the possibility of creating new inorganic heat-insulating materials based on liquid glass binder and mineral fillers. Within the framework of the article, the influence of various additives such as sawdust, chalk, coal and graphite on the physical and technical properties of an inorganic heat-insulating material is considered. The authors of the article proposed the compositions and conditions for obtaining materials that meet the regulatory requirements for materials and products for building thermal insulation

Titanium dioxide (TiO2) is widely applied in the field of pollution treatment due to its good catalytic properties and being an environmentally friendly material. In this study, TiO2 nanotubes were prepared from commercial TiO2 particles. The effects of carboxymethyl cellulose (CMC) and liquid glass (sodium silicate) on catalyst activity and catalyst adhesion on quartz tubes were investigated. Transmission microscopy (TEM), scanning microscope (SEM), X-ray diffraction (XRD), X-ray energy dispersive spectroscopy, Fourier transform infrared spectroscopy (FT-IR) were used for the characterization of the catalyst. In this study, the ethanol degradation ability of the catalyst, which was added with 0; 0.5; 1, and 1.5% liquid glass and calcined at 400 and 500oC, was determined. TiO2 nanotubes after preparation have a uniform diameter from 10-12 nm and an average length of about 150nm, specific surface area increases markedly compared to commercial granules (nearly 15 times). The results showed that CMC plays an important role in the thickness and distribution of TiO2 on the quartz surface. Liquid glass significantly affects the ethanol degradation efficiency.

The article is devoted to the development of resource-saving technology of porous granular materials for energy-efficient construction. The relevance of the work for international research is to emphasize expanding the raw material base of porous lightweight concrete aggregates at the expense of technogenic and substandard materials. The work aims to study the processes of porization of glass crystalline granules from polymineral raw materials mixtures. The novelty of the work lies in the establishment of regularities of thermal foaming of glass crystalline granules when using waste of magnetic separation of skarn-magnetite (WMS) ores and lignite clay. Studies of liquid glass mixtures with various mineral fillers revealed the possibility of the formation of a porous structure with the participation of opoka, WMS and lignite clay. This is due to the presence in the materials of substances that exhibit thermal activity with the release of a gas phase. The foaming efficiency of the investigated materials increases when combined with glass breakage. The addition of WMS and lignite clay to the glass mixture increases the pore size in comparison with foam glass. The influence of the composition of raw mixtures on the molding and stability of granules is determined. The addition of sodium carbonate helps to strengthen the raw granules and reduce the softening temperature of the mass. The composition of the molding mixture of glass breakage, liquid glass and a multicomponent additive is developed, which provides an improvement in the molding properties of the glass mass, foaming of granules at a temperature of 750 °C. Foam glass crystalline granules have polymodal porosity, characterized by a density of 330–350 kg/m3, a compressive strength of 3.2–3.7 MPa, and a thermal conductivity of 0.057–0.061 W/(m·°C). Accordingly, the developed granules have a high potential use in structural and heat-insulating concretes.

Abstract Information on the effect of a polysilicate solution obtained by mixing liquid glass with a silicic acid sol on the structure formation of lime compositions is presented. It was revealed that the amount of specific heat released when lime is wetted with a polysilicate solution is greater than when lime is wetted with water. This is due to the additionally released heat due to the chemical interaction of lime with polysilicate solution. It was found that the introduction of a polysilicate solution accelerates the development of plastic strength. For comparison, we used liquid glass and a sol of silicic acid as an additive. The synergistic effect of the influence of the polysilicate solution on the structure formation of lime finishing compositions was established, which manifests itself in the acceleration of the set plastic strength in comparison with silica sol and water glass. It has been established that the introduction of a polysilicate solution into the lime mixture formulation contributes to an increase in the resistance to slipping of the finishing layer. The optimal thickness of the finishing layer was determined, which is 20 mm, at which sliding from the vertical surface is not observed.

The main methods of improving the performance of granular thermal insulationmaterials based on liquid glass are chemical methods of their modification, which are based onchanging their structure through the use of special ingredients. At the same time, there is a need to introduce often a large number of components and individual technological operations, which is notalways technological. One of the promising methods of changing the physical state of substancesunder the action of an electromagnetic field is non-thermal treatment of microwave radiation. Theadvantages of using microwave radiation in comparison with the generally accepted methods ofmodification of materials are the transformation of their structure without significant changes in thetechnological process and the need to use additional components. Due to volumetric heating and themechanism of non-thermal action of microwave radiation on processing objects the duration of theirheating considerably decreases. When microwave heating of a liquid glass composition part of theenergy of electromagnetic radiation is converted into heat, which contributes to the intense swellingof the material, and the other part is aimed at structural changes in the material, which improve itsproperties due to the non-thermal effect of microwave radiation. Studies show that the best set ofperformance properties have granular materials obtained under the action of microwave radiationat a power of 650 W, which corresponds to a temperature of 110-120 0C. The required duration ofsuch heat treatment is 6-7 minutes. The closest to them in terms of coefficient of swelling are materialsobtained by convective heating at a temperature of 200 0C for 1 hour, but their physical andmechanical properties are much lower. Thus, it can be noted that the use of microwave radiationallows to obtain granular thermal insulation materials with a better set of performance properties atlower energy costs for their production.

The study of the thermal insulation market of Ukraine showed that the market is dominated by aerated concrete and silicates, which are used as thermal insulation materials at an average density of 300-500 kg / m3. Their disadvantages include high values of water absorption and hygroscopicity, as well as very low flexural strength, because this material does not have elasticity and the use of small bending forces leads to its cracking. Foam glass has a set of operational properties that meet the highest regulatory requirements. Foam glass is the strongest of all effective thermal insulation materials, but this material is fragile. It is sensitive to vibration - induced damage. In addition, the technology of production of foam glass is quite complex and requires high energy consumption, as a consequence, the cost of this material is high. Therefore, it was important to develop thermal insulation material with the appropriate level of performance while reducing production costs. This was achieved by using energy-saving microwave technology to swell liquid glass materials. This technology is based on the simultaneous swelling of the liquid glass granulate and the binder under microwave radiation, which, due to the volumetric heating of the liquid glass composition, allows to obtain a strong monolithic material with a rigid, homogeneous and mostly closed-porous structure. The production of thermal insulation materials is proposed to be carried out on the basis of liquid glass granulate, because the introduction of granules reduces the deformability and shrinkage of the material and prevents its cracking, increases its strength, because the granular material has a certain plastic deformation, reduces water hygroscopicity. granules swell to form a compacted shell, which slows down the absorption kinetics of water and its vapor. The monolithic granules are proposed to be carried out with a binder that foams not only due to the release of water, but also with the help of a gasifier, because this technology will allow uniform distribution of the binder in the intergranular space, thus forming a more homogeneous structure of the material, which has a positive effect on its physical and mechanical characteristics.

Abstract. The growth of requirements for the quality and performance of materials used for the construction of ship premises indicates the need to create new types of heat-insulating and structural and finishing products that can provide the stability of operational properties in a wide temperature range, high aesthetics and environmental safety. One of the means of providing these requirements is the use of non-flammable and non-toxic heat-insulating materials of increased strength during a fire. The processes of interaction between the components, the structure and phase composition of the obtained materials studied using complex X-ray phase, IR spectroscopic, and electron-optical methods of analysis. The main estimated quality indicators of the manufactured samples were taken: material density, thermal conductivity, ultimate strength in static bending, water absorption, also flammability and fire resistance, which determined in accordance with the current state standard and international ISO standards. The determination of the basic recipe composition of the raw mixture and the influence of technological parameters on the strength characteristics of the composite material was carried out using the method of mathematical planning of the experiment. The results obtained made it possible to fairly accurately outline the boundaries of variation of the composition of the vermiculite-silicate presscomposition and the main technological parameters. The results of the studies carried out correlate with the indicators of the physical, mechanical and technical properties of the varieties of the modified material, which makes it possible to purposefully search for the optimal composition and technological modes of manufacturing heat-insulating material for shipbuilding purposes. Using the methods of X-ray structural and electron-optical analysis, infrared spectroscopy, it has been established that as a result of heat treatment of the vermiculate-silicate presscomposition, complex physicochemical processes occur. It was found that in the system vermiculate–liquid glass –hardener, the chemical interaction of Al2O3 of vermiculate with liquid glass occurs with the formation of aluminosilicates. Additional crystallization at the vermiculite-water glass interface causes the formation of an intermediate layer of products, which prevents the occurrence of tension. The main regularities of directed synthesis in the system vermiculate–binder–hardener of neoplasms characterized by high strength and thermal stability in a wide temperature range have been studied. The optimal ratios of the main recipe components (vermiculate–binder–hardener), also a certain influence of water repellents, modifiers and reinforcing components on the processes of interaction between components, phase composition and structure of the composite have been determined.

The study analyses rigid polyurethane (PUR) foam modified with 10–30 wt.% sunflower press cake (SFP) and liquid glass-impregnated sunflower press cake (LG-SFP) particles and their impact on performance characteristics of PUR foams—foaming behaviour, rheology, thermal conductivity, compressive strength parallel and perpendicular to the foaming directions, tensile strength, dimensional stability, short-term water absorption by partial immersion, and thermal stability. Even though the dynamic viscosity and apparent density were increased for SFP and LG-SFP formulations, thermal conductivity values improved by 17% and 10%, respectively, when 30 wt.% of particles were incorporated. The addition of SFP and LG-SFP particles resulted in the formation of more structurally and dimensionally stable PUR foams with a smaller average cell size and a greater content of closed cells. At 30 wt.% of SFP and LG-SFP particles, compressive strength increased by 114% and 46% in the perpendicular direction, respectively, and by 71% and 67% in the parallel direction, respectively, while tensile strength showed an 89% and 85% higher performance at 30 wt.% SFP and LG-SFP particles loading. Furthermore, short-term water absorption for all SFP and LG-SFP modified PUR foam formulations was almost two times lower compared to the control foam. SFP particles reduced the thermal stability of modified PUR foams, but LG-SFP particles shifted the thermal decomposition temperatures towards higher ones.