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The effects of different types of bindings, the pressure of shaping and carbon-containing additives on the structural and energy characteristics, density, and mechanical properties of the shaped composite adsorbents prepared based on metal-organic framework structures are studied. Their adsorption behaviors are also examined for application to methane accumulation systems.

Sulphurremoval is a rather complicated metallurgical task, which require implementation of new energy-saving technologies, including metal desulphurization in induction furnaces. Results of analysis of different methods of metal desulphurization in the acidic induction furnaces. A technology of hot metal refining with Sulphurremoval by basic slags by extraction mechanism in the acidic induction furnaces proposed, tested and implemented at several plants. The essence of the xtraction mechanism applied to desulphurization method is as follows: particles of calcic slag involved by electromagnetic flows deep into an induction furnace. The surface layer of slag particles deoxidizes by carbon of the metal and silicon, resulting in the Sulphursolubility increases sharply due to its absorption by the metal surface layer of slag particles. Next, the metal flows deliver to the surface the slag particles saturated by Sulphur, the surface contacted with the furnace atmosphere, where the surface layer of slag particles is oxidized by oxygen of the atmosphere. It results in the Sulphursolubility decreasing sharply and after precipitating out of the slag; it oxidizes by oxygen to SO2 and removes into the furnace atmosphere. The process repeats multiply. The mechanism of theSulphur removal in the induction furnaces with acidic lining was studied at OJSC ZSMK foundry shop using IChT-10M furnaces when melting hot metal for melt bases and warmth-keeping jackets. To increase the proposed technology efficiency, the influence of different technological parameters on the rate and degree of metal desulphurization in the acidic induction furnaces of industrial frequency studied. Results of the study allowed to make a conclusion that induction furnaces, traditionally used for smelting of burden materials, convert into active refining melting facilities.

In this paper, the study of the adsorption of organic matter vapors (benzene, carbon tetrachloride, acetone) on the microporous carbon adsorbent FAS-3 in the region of pressures from 0.1 PA to 0.1 MPa and temperatures from 293 to 313 K was conducted, which showed sufficiently high adsorption characteristics of the used adsorbent in comparison with traditional absorbers. Microporous carbon adsorbent FAS-3 is quite new and still not fully understood. The purpose of this study was to determine the parameters of the adsorbent FAS-3, as well as the study of the processes of vapor adsorption of various organic substances on it. The microporous carbon adsorbent FAS-3, obtained on the basis of furfural, was used in the work. Obtaining spherical granules of the adsorbent FAS-3 was carried out in the result of liquid molding of a copolymer of furfural and epoxy resin on the basis of a fundamentally new process of combining the stages of blending monomer, molding the mixture in spherical product of the cured pellets. The activation of spherical grains of FAS-3 was carried out in a rotary kiln by a mixture of water vapor and carbon dioxide at a temperature of 850-900°C to burning that was consistent with the development of porosity in the adsorbent. The equilibrium values of vapor adsorption of substances on FAS-3 were measured on the gravimetric vacuum unit developed in the Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences. Regeneration of the adsorbent was carried out for 6 h at a temperature of 623 K to a pressure of 0.1 Pa. The maximum absolute measurement error was ± 0.01 mmol / g with 95% confidence. Measurement of vapor pressure of organic substances within 0.13 Pa-0.13 MPa was carried out by absolute pressure gauges M10, M1000, developed and manufactured in the Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences. The pressure measurement error by the manometer M10 in the range of 0.13 to 1330 Pa was ±0.066 Pa, and the manometer M1000 in the range from 13 Pa to 130 kPa was ±4.0 Pa.

The present study is aimed at the development of scientific and technological approaches to the production and exploitation of adsorption systems for natural gas storage at low temperatures. In this work, a monolithic microporous carbon adsorbent is proposed for the accumulation of natural gas; the comprehensive investigations of its structure and properties were carried out. The proposed adsorbent was used for filling up a mobile adsorption natural gas storage reservoir (an adsorber) equipped with the internal and external heat exchangers which provided different modes of fueling/delivery process. The adsorber endured the integrated reliability testing under isothermal, adiabatic and low-temperature conditions of gas fueling/delivery modes. The adsorption characteristics were determined at the pressures up to 10 MPa and within the temperature range from 238 to 293 K; the energy consumptions upon the processes of gas fueling and adsorber cooling were accessed depending on the fueling mode; the temperature variations occurring in the adsorber upon the gas fueling/delivery processes were studied within the pressure range from 0.05 to 10 MPa. Cyclic testings of the mobile adsorber of natural gas were performed to determine an influence of the cyclic loading on the adsorption capacity of the adsorbent.

The ratios between the film-sorbent parameters, sensitivity, and quartz sorption sensors’ sensitivity threshold have been obtained and analyzed. It has been demonstrated that, for the sorption sensors of vapors and gases based on polymer films, there exists a range of optimal values of thickness caused by its effect on the elastic properties. For acetone vapor sensors with a film made of polymethyl methacrylate (PMMA), this range is equal to 0.4–0.6% of the sensor’s plate thickness at the film deposition on both sides of the plate.

Adsorption of hydrogen in four types of activated carbons of different origin with specific micropore volumes ranging from 0.46 to 0.96 cm3/g is studied at temperatures of 303, 313, 323, and 333 K and pressures up to 20 MPa. The saturation adsorption of hydrogen vapors in the considered types of activated carbons is calculated at the hydrogen boiling point (20.38 K) and a pressure of 0.101 MPa using the Dubinin theory of volume filling of micropores (TVFM). The theoretical calculations show that the type FAS-2008 adsorbent, which is produced using liquid-phase furfural polymerization, has the highest adsorption capacity. Using the TVFM and taking into account linearity of the adsorption isosteres, we also estimate adsorption of hydrogen in the type AU3:5 slit-shaped microporous carbon adsorbent at a temperature of 303 K and pressures 10 and 20 MPa. The collected experimental data and theoretical calculations are compared to the data for 101 kPa and 20.38 K. The highest hydrogen adsorption, 7.9 wt %, at 20 MPa and 303 K is predicted for a model slit-shaped microporous graphene-based adsorbent, type AU3:5.

A microporous carbon adsorbent labeled as LCN was prepared by thermochemical synthesis from lignocellulose, and methane adsorption on it was studied within the temperature range from 303 to 333 K and at pressures up to 40 MPa. The total pore volume was determined to be 0.68 cm3/g. The maximum values of methane adsorption of ~14.5 mmol/g (23.2 wt %) were obtained at the temperature of 303 K and the pressure of 40 MPa. The calculated differential molar isosteric heat of methane adsorption is, on average, ~12–13 kJ/mol. Methane adsorption on LCN was calculated with the use of the Dubinin–Radushkevich and Dubinin–Astakhov equations, as well as the linearity of adsorption isosteres. It was shown that the Dubinin–Radushkevich and fundamental regularities of the theory of volume filling of micropores provide the best description of experimental data using only the standard structural and energy characteristics of the adsorbent.

For the first time, complex studies were carried out on adsorption deformation – sorbostriction of microporous carbon adsorbent FAS at adsorption of water and acetone vapors from the flow of carrier gas – nitrogen in non-equilibrium conditions. The results of this phenomenon were analyzed and the laws of the sorption of the microporous carbon adsorbent FAS during the adsorption of substances of different classes and different purposes in non-equilibrium conditions are established. In work a microporous carbon adsorbent FAS, obtained on the basis of furfural was used. Active coals on the basis of thermosetting plastics grades of FAS are significantly better than commercially-produced carbon adsorbents based on coal and peat on their mechanical properties and low ash content at a much greater development of the volume of the adsorbent micropores. We used the facility for studies of adsorption deformation of a solid adsorbent, manufactured in the Institute of Physical Chemistry and Electrochemistry of RAS. For the measurements we used a flow dilatometer, allowing measuring the adsorption deformation of the adsorbent while passing through it portions of the test substance or mixture in the carrier gas flow. It is shown that exit time of curves of sorbostriction to the maximum is individually for each of the studied substances, which enables you to use the effect of sorbostriction to detect the presence of certain substances in the mixture. The results of the wave sorbostriction of microporous carbon adsorbent FAS at adsorption of water and acetone vapors from the flow of carrier gas - nitrogen allow to conclude on the high selectivity of adsorption and the possibility of using the adsorbent as a sensor to control the content of these substances in a flow of nitrogen.

Adsorption of natural gas (methane) on the synthesized metal–organic framework (MOF) Al-BTC with specific surface area SBET = 1422 m2/g was studied at pressures up to 40 MPa and temperatures of 303, 313, 323, and 333 K. The maximum adsorption of methane on Al-BTC reaches 10.36 mmol/g at 303 K and 40 MPa, and the initial heat of adsorption is ~14 kJ/mol. The amount of methane accumulated in a system with Al-BTC attains a value of 120–130 m3(NTP)/m3 in a range of pressures from 3.5 to 10.0 MPa, which is the most relevant for methane accumulation. The volumes of methane stored in the systems with Al-BTC and without an adsorbent differ by a factor of about 2 at 3.5 MPa, there is almost no distinction between these options of methane storage at 7.0 and 20.0 MPa, and the amount of gas in the system without an adsorbent exceeds by 25% that in Al-BTC. The pressure range from 3.5 to 6.0 MPa is most efficient for the methane adsorption accumulation in the MOF structure Al-BTC. The absolute efficiency of methane adsorption accumulation increases with lowering of temperature.

The present work focused on the experimental study of the performance of a scaled system of adsorbed natural gas (ANG) storage and transportation based on carbon adsorbents. For this purpose, three different samples of activated carbons (AC) were prepared by varying the size of coconut shell char granules and steam activation conditions. The parameters of their porous structure, morphology, and chemical composition were determined from the nitrogen adsorption at 77 K, X-ray diffraction (XRD), small-angle X-ray scattering (SAXS), and scanning electron microscopy (SEM) measurements. The methane adsorption data measured within the temperature range from 178 to 360 K and at pressures up to 25 MPa enabled us to identify the most efficient adsorbent among the studied materials: AC-90S. The differential heats of methane adsorption on AC-90S were determined in order to simulate the gas charge/discharge processes in the ANG system using a mathematical model with consideration for thermal effects. The results of simulating the charge/discharge processes under two different conditions of heat exchange are consistent with the experimentally determined temperature distribution over a scaled ANG storage tank filled with the compacted AC-90S adsorbent and equipped with temperature sensors and heat-exchanger devices. The amounts of methane delivered from the ANG storage system employing AC-90S as an adsorbent differ from the model predictions by 4&ndash, 6%. Both the experiments and mathematical modeling showed that the thermal regulation of the ANG storage tank ensured the higher rates of charge/discharge processes compared to the thermal insulation.