Flow effects on silicate dissolution and ion transport at an aqueous interface

Phys Chem Chem Phys. 2019 Mar 27;21(13):6970-6975. doi: 10.1039/c9cp00640k.

Abstract

Flow effects on chemical reactions at a solid-liquid interface are fundamental to diverse technological applications but remain poorly understood from a molecular perspective. In this work, we demonstrate that the coupling between laminar flow and surface chemistry can be adequately described using classical density functional theory for ion distributions near the surface in conjunction with kinetics modeling and the Navier-Stokes equation. In good agreement with recent experiments, we find that flowing of fresh water over a silica surface may result in drastic changes in the rate of silica dissolution and, consequently, the surface charge density and the interfacial structure. A nonlinear streaming current is predicted when the surface reactions are disturbed by a laminar flow.