Isosteric heat for monolayer adsorption obtained from two-dimensional equations of state

The Reddy-O'Shea (RO) and Cuadros-Mulero (CM) equations of state for two-di mensional Lennard-Jones fluids have been used to obtain the isosteric heat of adsorption of simple fluids onto flat surfaces. The results are compared with a set of available experimental data, observing a large degree of agr eement, especially when the more simple CM equation of state is used. Anoth er advantage of the CM equation is that it is based on the Weeks-Chandler-A ndersen theory for simple fluids. In light of these results, we propose, as a first approach, the application of the CM model to describe the thermody namics of the adsorption of simple fluids onto flat surfaces.