Adsorption equilibria of chloropentafluoroethane on activated carbon powder

Abstract

An equilibrium study was conducted on the adsorption of chloropentafluoroethane (CFC-115, CF3CF2Cl) on activated carbon powder between 298.15 K and 373.15 K. Experimental data were fitted with several isotherm equations. Among the two-parameter equations, the BET equation showed the best results over the entire relative pressure range studied. When the pressure range was divided into two regions, a better result was obtained by applying the Langmuir equation in the lower pressure range and the BET equation in the higher relative pressure region. Among the three-parameter equations, the Langmuir-Freundlich equation gave better results than the Redrich-Peterson equation. The isosteric heat of adsorption of CFC-115 on the activated carbon powder was estimated. It was found to have the same order of magnitude with the heat of condensation, which indicates that the adsorption was primarily due to physical forces.