A model for water adsorption in activated carbon

In this paper we present a new model to describe the adsorption equilibrium of water in activated carbon. The model is based on the growth of the water cluster at the functional groups and the penetration of water clusters into the micropore in the form of pentamer, which has sufficiently high dispersion energy to remain in the micropore. This model is able to describe all possible behaviours of the water adsorption isotherm observed in the literature, ranging from type V for hydrophobic carbon to type IV for highly oxidised carbon. Testing of the model against a number of experimental data shows that the model is able to describe data well.