Collaborative Research: GOALI: Evaluating thermo-electro-adsorption mechanisms for waste-heat driven ion-separation processes

Vanderbilt University, Nashville TN

Investigators

Abstract

In the case of a natural disaster, drinking water quality may be significantly compromised. Remote areas may not have access to centralized water treatment. A low cost, modular water treatment device that operates using only electricity powered by renewable energy would address these concerns. Many current modular water treatment devices require elevated temperatures and pressures, which are not well suited for remote applications. In contrast, capacitive deionization is an electrochemical technique to desalinate water that uses only electricity and operates at ambient conditions. This project seeks to advance the energy efficiency of capacitive deionization to enable easily deployable water treatment. The premise of this work is to measure and evaluate through theory and experiments how thermal energy generated within a capacitive deionization cell and applied external to the cell (through waste heat) affect electric double layer salt removal dynamics. We intend to probe local electric double layer properties through performing in situ analytical measurements (calorimetry, coulometry, microscopy, scattering). Complimentary bulk (system level) experiments will be used to evaluate the energetics associated with electric double layer based separations in dilute aqueous systems (brackish water treatment). Ultimately, the aim is to better understand how waste heat can be best utilized, to aid ion packing and maximize desalination performance. This is fundamental to many fields of electrochemistry, colloid science and an emerging issue in water treatment. This approach will also provide a new benchmark for studying these electrochemical separation technologies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.