Measurement and Modeling of Adsorption of Lower Hydrocarbons on Activated Carbon

This work reports adsorption isotherms for C-1 to C-6 hydrocarbons on activated carbon at three different temperatures (293 K, 318 K, and 358 K) over a wide range of pressure (0 bar to 100 bar). The isotherms were measured using a standard gravimetric method. The experimental data were correlated and compared using Toth, modified virial, and potential theory models. On the basis of the adsorption potential, characteristic curves were also generated for methane, ethane, propane, isobutane, n-pentane, and n-hexane on activated carbon over broad ranges of pressure and temperatures. The micropore volume of the activated carbon predicted from potential theory was in good agreement with those obtained using a N-2 isotherm measured at 77 K. The enthalpy of adsorption at zero loading was found to increase linearly with the carbon number.