Vapor-Liquid phase transition of associating fluids in a functionalized cylindrical pore: a Monte Carlo study

Abstract

In this study, we investigate the phase behaviour of associating fluids with two interacting sites inside a functionalised cylindrical pore using Grand Canonical Monte Carlo simulations. The structural behaviour of the coexisting liquid and vapor phases is characterised by the radial density, orientation, and bond formation inside cylindrical pores of different radii. The critical properties of the phase diagrams of the confined fluids were investigated as functions of the associating strengths at different pore sizes. The impact of site strength on the phase diagram is characterised by the critical and structural properties of the coexisting phases inside the cylindrical pore. The organisation of the associating fluids near the pore surface strongly depends on the surface – site interaction with the interfacial fluid molecules that propagate to the bulk regime of the system. Thus, the surface site density is a crucial parameter for manipulating the properties of coexisting phases and critical properties of the phase diagram.