This article presents the adsorption isotherms of methane onto two different types of activated carbons, namely, Maxsorb III and ACF (A-20) at temperatures from (5 to 75)°C and pressures up to 2.5 MPa. The volumetric technique has been employed to measure the adsorption isotherms. The experimental results presented herein demonstrate the improved accuracy of the uptake values compared with previous measurement techniques for similar adsorbate-adsorbent combinations. The results are analyzed with various adsorption isotherm models. The heat of adsorption, which is concentration and temperature dependent, has been calculated from the measured isotherm data. Henry's law coefficients for these adsorbent-methane pairs are also evaluated at various temperatures.

This paper presents the experimentally measured adsorption isotherm data for methane onto the pitch-based activated carbon type Maxsorb III for temperatures ranging from (120 to 220) K and pressures up to 1.4 MPa. These data are useful to study adsorbed natural gas (ANG) storage systems when the low temperature natural gas regasified from the liquid phase is considered to charge in the storage chamber. Adsorption parameters were evaluated from the isotherm data using the Tóth and Dubinin−Astakhov models. The isosteric heat of adsorption, which is concentration- and temperature-dependent, is extracted from the data. The Henry’s law coefficients for the methane/Maxsorb III pairs are evaluated at various temperatures.