Adsorption of Methane Vapors on a Micro-Mesoporous Carbon Adsorbent During Long-Term Storage of Liquefied Natural Gas

—The study investigated the physicochemical and adsorption characteristics of a micro-mesoporous carbon adsorbent obtained from wood waste by a thermochemical method with respect to the processes of the accumulation of liquefied natural gas vapors in long-term storage systems. X-ray diffraction analysis of the adsorbent showed that, as a result of synthesis of the adsorbent, its structure was an amorphous carbon phase, without signs of graphite-like phases characteristic of coal obtained from other types of raw materials. In turn, the developed porous structure of the adsorbent is represented by both micro- and mesopores, with a wide size distribution: the total pore volume was about 1.7 cm 3 /g. The sorption characteristics of the adsorbent at temperatures of 111.7–160 K and pressures up to 0.6 MPa were calculated based on the linearity of experimental isotherms at T from 303 to 333 K and the contribution from adsorption on the surface of mesopores in the monolayer and the capillary condensation effect (CCE). Based on sorption data, it is shown that the presence of mesopores has a predominant effect on the adsorption accumulation efficiency due to the contribution of CCE, providing an active capacity of cryogenic sorption accumulators at a level of 450 m 3 (NTP)/m 3 .