Adsorption of Hydrogen in Microporous Carbon Adsorbents of Different Origin

Abstract

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.