Deterministic models for the prediction of ion adsorption-desorption processes in capacitive desalination devices
With depleting fresh water sources across the world, there is a growing interest in desalination. Capacitive deionization (CDI) is considered to be a promising option for the desalination of brackish water.
In this project we will use improved-modified Donnan (i-mD) model to describe electro-migration, electroadsorption and desorption processes occurring within a flow-through CDI unit. Mathematical functions with commonly expressed parameter-sets for CDI electrode materials will be developed, to widen its scope to integrate processes where the fluid flow takes place perpendicular to the electrode plane. The functions will then be extended to incorporate the effects of nanostructured coatings on the electrode surface and externally controllable parameters like flow rate, temperature and potential, to predict electrosorption dynamics. Additionally, computational fluid dynamics (CFD) models will be developed to explore the relationship between pressure drop, fluid flow rate, surface fluid distribution and electrode material properties. The equations will be compiled into a Finite Element Model that will be validated using activated carbon cloth (ACC) as electrode material in a strictly flow-through CDI operation. The research, development and measurements will be carried out at Functional Materials unit at KTH within a period of four years. In brief, the project outlines a method to build deterministic models for statistically available data on electrosorption processes.
Project leader: Joydeep Dutta
Project period: 2019-2022
Financing: Swedish Research Council (Vetenskapsrådet)
