The adsorption isotherm can reflect the adsorption capacity
of the adsorbent. In this paper, the adsorption properties
of all samples were investigated. The results are shown in
Figure 5. The CO2 adsorption capacities of all samples increased
rapidly with the change of pressure at 25 ◦C. However,
the behavior of CH4 adsorption was not same as that of
CO2 adsorption, especially over the P-AC sample.