Supercapacitive microbial desalination cells: New class of power generating devices for reduction of salinity content

Abad, Fernando Benito; Serov, Alexey; Kodali, Mounika; Howe, Kerry J.; Soavi, Francesca; Atanassov, Plamen; Santoro, Carlo

Abstract

© 2017 The Author(s) In this work, the electrodes of a microbial desalination cell (MDC) are investigated as the positive and negative electrodes of an internal supercapacitor. The resulting system has been named a supercapacitive microbial desalination cell (SC-MDC). The electrodes are self-polarized by the red-ox reactions and therefore the anode acts as a negative electrode and the cathode as a positive electrode of the internal supercapacitor. In order to overcome cathodic losses, an additional capacitive electrode (AdE) was added and short-circuited with the SC-MDC cathode (SC-MDC-AdE). A total of 7600 discharge/self-recharge cycles (equivalent to 44 h of operation) of SC-MDC-AdE with a desalination chamber filled with an aqueous solution of 30 g L−1 NaCl are reported. The same reactor system was operated with real seawater collected from Pacific Ocean for 88 h (15,100 cycles). Maximum power generated was 1.63 ± 0.04 W m−2 for SC-MDC and 3.01 ± 0.01 W m−2 for SC-MDC-AdE. Solution conductivity in the desalination reactor decreased by ∼50% after 23 h and by more than 60% after 44 h. There was no observable change in the pH during cell operation. Power/current pulses were generated without an external power supply.

• Journal Article Type: Article
• Acceptance Date: Oct 14, 2017
• Publication Date: Dec 15, 2017
• Deposit Date: Apr 19, 2018
• Publicly Available Date: May 2, 2018
• Journal: Applied Energy
• Print ISSN: 0306-2619
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 208
• Pages: 25-36
• DOI: https://doi.org/10.1016/j.apenergy.2017.10.056
• Keywords: Supercapacitive Microbial Desalination Cell (SC-MDC), Additional Electrode (AdE), power/current pulses, high power generation, transport phenomena
• Public URL: https://uwe-repository.worktribe.com/output/879628
• Publisher URL: https://doi.org/10.1016/j.apenergy.2017.10.056
• Contract Date: Apr 19, 2018