  Reverse Osmosis(RO) membranes are widespread nowadays for separating the
solvent from a solution. RO membranes are made of polymer matrix. Experiments
show changes in relative interaction of solvent and solute with RO membrane
matrix lead to changes in solvent permeation, solute rejection and fouling.
Here we study microscopically separation of binary mixture through RO polymeric
membrane using Molecular dynamics simulation to rationalize the experimental
observations in terms a simple model. We find better solvent permeation and
solute rejection with increasing interaction between solute and membrane with
increase in fouling of solute inside membrane. We also find that stronger
solvent membrane interaction reduces fouling. However, this leads to poorer
performance of RO in terms of solvent permeation and solute rejection.
