Lab-scale experiments with a monovalent ion selective membrane capacitive deionization for nitrate removal

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

Groundwater with high nitrate concentrations requires treatment before potable use. Conventional treatment methods such as nanofiltration and reverse osmosis can be used for desalination of most solutes. In contrast, a monovalent selective membrane capacitive deionization (mMCDI) can be used for selective nitrate removal. We use a nanofiltration membrane and anion exchange membranes with an additional neutral layer (AEM-Neutral) or a polyamide layer (AEM-PA) for selective nitrate removal with mMCDI by using a solution of mixed monovalent and polyvalent ions. Monovalent ion selectivity in short-term experiments is up to 17.3 with a nanofiltration membrane, up to 1.7 for AEM-Neutral and up to 5.2 for AEM-PA, whereby the specific energy consumption and water recovery depends on cell structure, applied electric voltage, flow rate and desorption time. Selective nitrate removal with AEM-PA or AEM-Neutral at 0.8 V demonstrated a specific energy consumption of 2 Wh g-1 removed nitrate, lower than pressure-driven membrane processes.

Details

Original languageEnglish
Article number100288
Number of pages16
JournalWater Resources and Industry
Volume33
Publication statusPublished - Jun 2025
Peer-reviewedYes

External IDs

ORCID /0000-0002-6355-9122/work/205331389

Keywords

Sustainable Development Goals

Keywords

  • Membrane capacitive deionization, Monovalent ions, Nitrate, Partial desalination, Selectivity