Abstract
Conventional technologies for ammonium removal from wastewaters are based on biological conversion to nitrogen gas, eliminating the possibility for ammonium recovery. A new electrochemical approach was developed here to selectively remove ammonium using two copper hexacyanoferrate (CuHCF) battery electrodes separated by an anion exchange membrane, at low applied voltages (0.1 to 0.3 V). The CuHCF battery electrodes removed NH4+ from a synthetic wastewater with a selectivity >5 (i.e., percent removed of NH4+/percent removed of Na+) when operated with a 0.1 V applied voltage, despite the much higher initial Na+ concentration in the sample (20 mM) than NH4+ (5 mM). In contrast, we observed only negligible selective removal of NH4+ over Na+ (4 versus Na+ in the presence of other competing cations. These results demonstrate that CuHCF electrodes can be used to selectively remove NH4+ from various waters containing multiple ions.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 578-583 |
| Number of pages | 6 |
| Journal | Environmental Science & Technology Letters |
| Volume | 5 |
| Issue number | 9 |
| DOIs | |
| State | Published - Aug 13 2018 |
| Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledged KAUST grant number(s): OSR-2017-CPF-2907-02
Acknowledgements: We thank Dr. Ruggero Rossi for the wastewater analysis. This research was supported by the National Science Foundation through CBET-1464891, the King Abdullah University of Science and Technology (KAUST; OSR-2017-CPF-2907-02), and Penn State University.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.