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Physicochemical regularities are studied for the synthesis of molded active carbons based on coconut shells and peat, with a latex emulsion and a carboxymethyl cellulose (CMC) sodium salt solution being used as binding agents. The materials are obtained at compacting pressures of 25, 50, and 100 MPa. The specific surface areas of the composite samples obtained from peat and coconut shells are SBET ≈ 1320 and ≈1290 m2/g, respectively. The specific micropore volumes of the composites based on peat and coconut shells are W0 = 0.50 and 0.45 cm3/g, respectively. Latex-modified carbon samples have a higher bulk density than those molded with CMC. The molding of the active carbons is accompanied by partial degradation of their porous structure. The Dubinin theory of volume filling of micropores (TVFM) has been employed to calculate the values of adsorption and active specific capacity of the molded adsorbents with respect to methane at a temperature of 273 K and a pressure of up to 100 bar. The experimental and calculated data have shown that the active capacity of the new microporous carbon composite materials may be as large as 180 m3 (NTP)/m3, when the pressure drops from 100 to 1 bar. It has been concluded that it is reasonable to employ the TVFM for preliminary calculations of the parameters of adsorption systems used for natural gas storage.

Relative linear adsorption-induced deformation of granules of AR-V microporous carbon adsorbent has been measured upon n-octane adsorption at pressures p of 1 Pa to 1.6 kPa and temperatures T = 273, 293, 313, 353, and 393 K. At p > 200 Pa, the adsorption-induced deformation is positive and grows with p throughout the considered temperature range. Under isobaric conditions, the adsorption-induced deformation and the slope of deformation isotherms increase as T decreases. At p 350 K, the adsorbent expands throughout the pressure range. Molecular dynamics simulation has been employed to study the structure of n-octane adsorption associates in model slit-like micropores having a width corresponding to the effective size of micropores in AR-V adsorbent calculated in terms of the theory of volume filling of micropores. The structure of the adsorption associates has been related to the characteristic features of the adsorption-induced deformation of AR-V adsorbent.

A new carbon microporous adsorbent denoted as MPU-007 with a specific micropore volume as large as 1.44 cm3/g has been synthesized. Hydrogen adsorption on this adsorbent has been studied at temperatures of 303, 313, 323, and 333 K and pressures of up to 15 MPa. The maximum adsorption value is 12 mmol/g (2.4 wt %) at 15 MPa and 303 K. The obtained data have been compared with the results of previous studies of hydrogen adsorption on a number of microporous carbon adsorbents with increasing specific micropore volume. It has been shown that the differential molar isosteric heats of hydrogen adsorption decrease from 10 to 4 kJ/mol with an increase in the degree of micropore filling.

Relative linear deformation of AUK microporous carbon adsorbent with a narrow pore size distribution has been measured upon n-octane adsorption at pressures of 1 Pa to 1.6 kPa and temperatures of 273, 293, 313, 353, and 393 K. Throughout the studied temperature range, adsorption-induced deformation curves exhibit a similar behavior. At low and moderate degrees of micropore filling, the adsorbent remains almost undeformed, while it dramatically expands in the region of high degrees of filling. Adsorption of n-octane molecules in a model slitlike pore, the average effective width of which corresponds to the width of micropores in the AUK adsorbent, has been numerically simulated by the molecular dynamics method. It has been shown that, in the initial and middle regions of micropore filling, the behavior of the deformation dependences is determined by the ratio between the sizes of n-octane molecules and micropores. At high degrees of filling, the formation of adsorption associates in the micropores leads to a rise in the internal pressure and a drastic expansion of the adsorbent. The compressibility of AUK has been calculated, and the results obtained correspond to the data published previously.

A procedure has been proposed for the self-assembly of carbon nanotubes into arrays with the use of coordinating molecules and the development of secondary porosity in the resulting supramolecular structures. Molecular dynamics has been employed to study the formation of such structures and determine the effective radius of pores formed in them. The average micropore sizes in the obtained supramolecular structures have been related to the sizes of coordinating molecules and their orientation with respect to nanotube surface. Adsorption of methane and hydrogen on such model systems has been calculated on the basis of the theory of volume filling of micropores. It has been shown that the porosity resulting from the organization of the nanotubes into arrays with the help of coordinating molecules makes it possible to accumulate methane and hydrogen at the level of the best model adsorbents.

Adsorption-induced deformation of AR-V and AUK carbon adsorbents and NaX zeolite has been studied upon adsorption of n-С5Н12, n-С6Н18, n-С7Н16, and CO2 at temperatures of 193−423 K. It has been shown that adsorption-induced deformation is positive upon the physical adsorption of gases and vapors on the surface of a nonporous (macroporous) solid when the excess adsorption is positive. When calculating the adsorption-induced deformation in the region of the capillary-condensation filling of mesopores, the additional pressure in capillaries, which is negative (contraction of an adsorbent), must be taken into account in the case of wetting a solid surface with a liquid adsorbate. The compressibility of AUK microporous carbon adsorbent as a porous solid is almost independent of the temperature and the properties of an adsorbate, and, for adsorption of n-C5H10 and n-C7H16 hydrocarbons and CO2, it is γа = (5.6 ± 0.6) × 10−6 bar−1. The compressibility of AUK adsorbent appears to be 87% higher than that of nonporous graphite.

Methane adsorption on a microporous carbon adsorbent with a bimodal pore size distribution is studied at temperatures of 303–333 K at pressures up to 30 MPa. The total micropore volume of the adsorbent, as determined by the Dubinin method, is as large as 1.02 cm3/g. Maximum values of methane adsorption of ≈18 mmol/g are attained at a temperature of 303 K and a pressure of 30 MPa. Methane adsorption isosteres are plotted based on experimental data, and adsorption equilibria at low temperatures are calculated using the linearity of the plots. Experimental isotherms of methane adsorption are compared with the isotherms calculated by the Dubinin–Nikolaev equation with variations in parameters E and n. Temperature dependences of these parameters are determined. Specific characteristics of methane adsorption accumulation are calculated.