Adsorption of Xe, Kr, Ar, N 2 , O 2 , H 2 CH 4 , CO 2 , He, and freons by PAU-10 and ACC microporous carbon adsorbents as well as by A and X zeolites was investigated over a wide range of pressures (0.1 Pa -20 MPa) and temperatures (77, 120-600 K). The amount of gases, vapors and liquids adsorbed by microporous adsorbents increases steadily with increasing pressure and does not change dramatically if phase transitions occur in the adsorptive. Isosteres of adsorption constructed as a curve of ln P against f (1/T ) a retain a linear form over a wide range of pressures and temperatures. The slope of isosteres does not vary on going through the critical temperature of the gaseous phase. At high pressures, due to non-ideality of the gaseous phase and non-inert behavior of the adsorbent the differential molar heat of adsorption is dependent on temperature. At high fillings of micropores the differential molar isosteric heat capacities of adsorption systems show maxima that indicate the occurrence of structural rearrangements in the adsorbate.

Natural gas (methane) forms an essential part of modern power supply. However, natural gas storage and transportation are associated with fire and explosion hazard, which restricts extensive application of natural gas as a fuel. The adsorption technique is among the most promising and safe ways for natural gas storage and transportation, which allows a significant increase in the methane density up to values characteristic of liquids as a result of physical adsorption in microporous adsorbents at moderate pressures. The review considers adsorption systems for natural gas (methane) storage based on metal-organic frameworks, which possess high characteristic energy of adsorption and a regular nanoporous structure with high pore volumes and specific surface areas. The possibility of controlling the porous structure and physicochemical behaviour of metal-organic frameworks during their synthesis and functionalization is analyzed, including the fabrication of composites and shaping, which may enhance their performance in the adsorption storage and transportation of natural gas. The bibliography includes 315 references.

The use of gas fuel has considerable environmental advantages over traditional types of fuel based on petroleum products or fossil coal. The adsorption technology for methane (natural gas) uptake, storage and transportation can serve as a connecting link in gas supply to customers. The review considers characteristics of adsorption systems for methane storage. The key methods used for the synthesis of microporous carbon adsorbents based on various organic and inorganic carbon-containing compounds are described. Methods for increasing the efficiency of methane storage systems based on carbon adsorbents are analyzed. Theoretical approaches to optimization of the properties of methane – carbon adsorbent systems are discussed. The bibliography includes 174 references.

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The temperature-and methane adsorption-induced deformations of microporous activated carbon Sorbonorit-4 were measured by in situ dilatometry over a wide range of temperatures and pressures. The thermal expansion coefficient of Sorbonorit-4 in vacuum increased linearly with temperature within a range of 293−573 K. Methane adsorption in Sorbonorit-4 induced its contraction at low pressures and temperatures or expansion at high temperatures throughout the entire pressure range. An inversion of the temperature dependence of adsorption-induced strain (AIS) of Sorbonorit-4 was found. At low pressures and temperatures below 300 K, the AIS isotherm showed a contraction of Sorbonorit-4; its magnitude and corresponding pressure interval decreased with temperature. At T > 300 K, the temperature rise was accompanied by an adsorption-induced expansion of Sorbonorit-4 up to 0.08% at 393 K. At high pressures, the expansion decreased from 0.45 to 0.13% when the temperature increased from 213 to 393 K. The AIS of Sorbonorit-4 and differential isosteric heat of adsorption presented as functions of methane uptake changed within the same intervals of adsorption values, reflecting variations in the state of adsorbed molecules determined by contributions from the adsorbate−adsorbent and adsorbate−adsorbate interactions. The obtained results are essential for practical use of carbon adsorbents for natural gas storage.