Adsorption of Methane onto Microporous Activated Carbon in a Volumetric Storage System

Abstract ES-103(1) microporous carbon adsorbent with specific micropore volume W0 = 0.80 cm3/g and pore width Х0 = 1.32 nm was prepared by thermochemical activation of wood waste in Н3РО4 at 1173 K. The specific BET surface of the adsorbent was SBET = 2115 m2/g. At 303 K and 20 MPa, the methane-adsorption capacity of the adsorbent reached ~22 wt %. In the main region of micropore fillings, the differential molar isosteric heats of methane adsorption gradually dropped from ~16 to 12 kJ/mol. To increase the energy of methane adsorption, it is necessary to use systems that provide a possibility additionally to increase the energy of adsorption due to the energy of adsorbate associating in micropores. At a pressure of 10 MPa, the methane volumetric density in ES-103(1) adsorbent compacted with a binder achieved 200 m3(NTP)/m3.