A1 Journal article (refereed), original research

Nitrate removal and recovery by capacitive deionization (CDI)


Open Access hybrid publication

LUT Authors / Editors

Publication Details
Authors: Pastushok Olga, Zhao Feiping, Ramasamy Deepika L., Sillanpää Mika
Publisher: Elsevier
Publication year: 2019
Language: English
Related journal or series: Chemical Engineering Journal
Journal acronym: Chem Eng J
Volume number: 375
ISSN: 1385-8947
eISSN: 1873-3212
JUFO level of this publication: 3
Open Access: Open Access hybrid publication

Abstract

Capacitive deionization (CDI), an emerging technology, has attracted
attention recently and has been applied for various purposes. Herein, we
investigated the application of a CDI system using activated carbon
(AC) electrodes for nitrate removal and recovery in the scope of
domestic wastewater treatment. The electrochemical behavior and
structural parameters of AC electrodes were investigated as a part of
this work. CDI electrodes were fabricated from microporous activated
carbon, and the specific surface area of the electrode material was
210 m2/g. The negative effect of polymeric binder on the AC
electrodes performance was observed as well. The specific capacitance of
the fabricated AC electrodes at 40 mV/s scan rate was 0.5 F/g and
19 F/g for 1 and 1000 mM electrolyte (NH4NO3),
respectively. The CDI performance was examined as a function of flow
rate (2, 4, 9, 14 mL/min), applied voltage (0.6, 0.8, 1.0, 1.2 V), and
initial nitrate concentration (10, 25, 50, 70 mg/L) in single-pass (SP)
mode. Regeneration performance and recovery efficiency of the CDI cell
were observed during 5 subsequent operational cycles. The recovery
efficiency of nitrate ions from low salinity water was 21%, while the
electrosorption capacity of 5.5 mg/g and removal efficiency of 48% was
achieved. Presence of the competitive ions in the tested solution
resulted in a slight decrease (~10%) of nitrate removal efficiency.


Last updated on 2020-20-03 at 10:03