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arXiv · 1609.00540

Interplay between adsorption and hydrodynamics in nanochannels: towards tunable membranes

Sela Samin·René van Roij
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Abstract

We study how adsorption of a near-critical binary mixture in a nanopore is modified by flow inside the pore. We identify three types of steady states upon variation of the pore Péclet number (${\rm Pe}_p$), which can be reversibly accessed by the application of an external pressure. Interestingly, for small ${\rm Pe}_p$ the pore acts as a weakly selective membrane which separates the mixture. For intermediate ${\rm Pe}_p$, the flow effectively shifts the adsorption in the pore thereby opening possibilities for enhanced and tunable solute transport through the pore. For large ${\rm Pe}_p$, the adsorption is progressively reduced inside the pore, accompanied by a long ranged dispersion of the mixture far from the pore.

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Sela Samin, René van Roij. 2016-11-15. Interplay between adsorption and hydrodynamics in nanochannels: towards tunable membranes. https://doi.org/10.1103/physrevlett.118.014502

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