Experimental and Modeling Study of the Adsorption of Supercritical Methane on a High Surface Activated Carbon

Abstract

The adsorption of methane on an activated carbon of high surface was measured in the range of 233−333 K and 0−10 MPa. The isotherms showed a considerably different feature than that measured on low surface carbon. A maximum appeared on isotherms at relatively low temperatures. All the experimental isotherms were well modeled by the Langmuir−Freundlich equation. The difference between the measured and the so-called absolute adsorption was properly accounted for in modeling. An assumption of monolayer adsorbate adsorbed was included in the model. The layer volume evaluated was consistent with the pore volume of adsorbent reported by CO2 adsorption. The intermolecular distance in the adsorbed phase was evaluated from a model parameter. This intermolecular distance was compared with that in the free sate, which revealed a basic picture of the physical state of the adsorbed phase at above-critical temperatures.

Enrichment of coal‐bed methane by PSA complemented with CO2 displacement

“…Details of the measurement were previously described. 33 The adsorbed amount of CO 2 was much higher than that of CH 4 and N 2 . The breakthrough curves of gas mixture He/ CH 4 /N 2 were also collected at 298 K and shown in Figure 4.…”

Determination of the Adsorbed Phase Volume and Its Application in Isotherm Modeling for the Adsorption of Supercritical Nitrogen on Activated Carbon

“…The reference cell was kept at 303 K with a constancy of ±0.1 K. A pressure transmitter model PAA-23/8465.1-200 manufactured by Keller Druckmesstechnik, Switzerland with precision of 0.05% was used to measure the pressure in the reference cell. The activated carbon used in this study is the same as that applied for studying methane adsorption (12). The surface area and micropore volume reported by CO 2 adsorption at 273 K was 3106 m 2 /g and 1.29 ml/g respectively.…”

Activated Carbon Preparation from Lignin by H3PO4 Activation and Its Application to Gas Separation

“…For reasons of simplicity, the complete reproduction of all the formula for calculating the absolute adsorption was omitted. The detailed reproduction of these formulas can be found elsewhere [24].…”