Molecular modeling of fluid separations using membranes: effect of molecular forces on mass transfer rates

We report computer simulations of semi-permeable membranes using the method of molecular dynamics, to study solutions undergoing osmosis and reverse o smosis. These studies have been carried out at steady state, by periodicall y recycling solvent molecules that permeate the semi-permeable membrane. Th e method has been used to investigate the effect of a range of molecular fo rces, state conditions, and membrane morphology on the mass transfer rate o f solvents across the membrane. These results could be used to test the acc uracy of continuum, micro-continuum and statistical mechanical theories for transport across membranes, apart from being of intrinsic fundamental inte rest. (C) 1999 Elsevier Science S.A. All rights reserved.