Nanopore-based desalination subject to simultaneously applied pressure gradient and gating potential
Journal
Journal of Colloid and Interface Science
Journal Volume
594
Pages
737-744
Date Issued
2021
Author(s)
Abstract
The performance of a dielectric membrane in desalting is assessed by considering a cylindrical nanopore, surface modified by a dielectric layer, subject to simultaneously applied pressure gradient and gating potential. The charged conditions of the nanopore can be tuned by modulating the applied gating potential so that it can be used for rejecting different types of salt. In general, the thinner the dielectric layer and/or the larger its dielectric constant the better the salt rejection performance. For example, if the thickness of the dielectric layer is 10 nm with a relative dielectric constant of 25, applying a pressure difference of 5 MPa and gating potential of 1 V yields 49% rejection. However, it declines to 9% if the relative dielectric constant is lowered to 5 with other parameters fixed, and 23% if that thickness is 50 nm with other parameters fixed. The results of numerical simulation based on various types of single salt and mixture salts with ions of different valences reveal that the type of ions which need be filtrated can be selected effectively through regulating the gating potential. ? 2021 Elsevier Inc.
Subjects
Desalination; Pressure gradient; Cylindrical nanopores; Dielectric layer; Dielectric membranes; Pressure differences; Relative dielectric constant; Salt rejections; Surface-modified; Nanopores; chloride; ion; potassium ion; sulfate; Article; channel gating; desalination; dielectric constant; parameters; pressure gradient; priority journal; simulation; surface property; thickness
SDGs
Type
journal article