Concentration gradient driven molecular dynamics: a new method for simulations of membrane permeation and separation. Issue 5 (24th March 2017) - Ozcan, Aydin
Abstract : We introduce a new non-equilibrium molecular dynamics method which creates a continuous and steady-state concentration gradient along a membrane. Abstract : In this study, we introduce a new non-equilibrium molecular dynamics simulation method to perform simulations of concentration driven membrane permeation processes. The methodology is based on the application of a non-conservative bias force controlling the concentration of species at the inlet and outlet of a membrane. We demonstrate our method for pure methane, ethane and ethylene permeation and for ethane/ethylene separation through a flexible ZIF-8 membrane. Results show that a stationary concentration gradient is maintained across the membrane, realistically simulating an out-of-equilibrium diffusive process, and the computed permeabilities and selectivity are in good agreement with experimental results.