Water transport in reverse osmosis membranes is governed by pore flow, not a solution-diffusion mechanism
Yale University · University of Wisconsin–Madison · +1 more institution
Abstract
We performed nonequilibrium molecular dynamics (NEMD) simulations and solvent permeation experiments to unravel the mechanism of water transport in reverse osmosis (RO) membranes. The NEMD simulations reveal that water transport is driven by a pressure gradient within the membranes, not by a water concentration gradient, in marked contrast to the classic solution-diffusion model. We further show that water molecules travel as clusters through a network of pores that are transiently connected. Permeation experiments with water and organic solvents using polyamide and cellulose triacetate RO membranes showed that solvent permeance depends on the membrane pore size, kinetic diameter of solvent molecules, and…
Citation impact
- FWCI
- 23.36
- Percentile
- 100%
- References
- 89
Authors
7Topics & keywords
- Permeance
- Membrane
- Permeation
- Solvent
- Reverse osmosis
- Diffusion
- Water transport
- Chemical engineering
- Clean water and sanitation