TY - JOUR
T1 - Efficient recovery of nitrate from municipal wastewater via MCDI using anion-exchange polymer coated electrode embedded with nitrate selective resin
AU - Kim, David Inhyuk
AU - Gonzales, Ralph Rolly
AU - Dorji, Pema
AU - Gwak, Gimun
AU - Phuntsho, Sherub
AU - Hong, Seungkwan
AU - Shon, Hokyong
N1 - Funding Information:
This work was supported by Korea Environmental Industry and Technology Institute (KEITI) through Industrial Facilities & Infrastructure Research Program, funded by Korea Ministry of Environment (MOE) ( RE201901117 ).
Publisher Copyright:
© 2020
PY - 2020/6/15
Y1 - 2020/6/15
N2 - A NO3−—selective carbon electrode coated with an anion-selective polymer with polystyrenic macroporous nitrate—selective A520E resin particles (in chloride form; particle size: 300–1200 μm) was fabricated for desalination of municipal wastewater and NO3− recovery during membrane capacitive deionization (MCI). Several issues, such as electrosorption/regeneration efficiency, selectivity of NO3−, and removal from real wastewater, were addressed to demonstrate the suitability of coated electrodes. The NO3−—selective electrode induced better electrosorption than the conventional MCDI, whereas its salt adsorption capacity was lower than that of the ion-exchange (IX) layer only coated one. The mole fraction of NO3− adsorption kept increased even after saturation by replacing Cl− adsorbed on the resin coating layer. However, the desorption efficiency of NO3− was retarded as it was exchanged with Cl− and temporarily intercepted in the resin of the IX layer, during ion migration towards the bulk brine solution. 81.5% of NO3− was removed with better NO3− selectivity from real municipal wastewater, and a high concentration of NO3− brine was obtained through successive operation. However, the poorly selective NO3− desorption, which limits its enrichment due to the reverse ionic-strength gradient induced by the high concentration brine, needs to be mitigated to prove its effective recovery.
AB - A NO3−—selective carbon electrode coated with an anion-selective polymer with polystyrenic macroporous nitrate—selective A520E resin particles (in chloride form; particle size: 300–1200 μm) was fabricated for desalination of municipal wastewater and NO3− recovery during membrane capacitive deionization (MCI). Several issues, such as electrosorption/regeneration efficiency, selectivity of NO3−, and removal from real wastewater, were addressed to demonstrate the suitability of coated electrodes. The NO3−—selective electrode induced better electrosorption than the conventional MCDI, whereas its salt adsorption capacity was lower than that of the ion-exchange (IX) layer only coated one. The mole fraction of NO3− adsorption kept increased even after saturation by replacing Cl− adsorbed on the resin coating layer. However, the desorption efficiency of NO3− was retarded as it was exchanged with Cl− and temporarily intercepted in the resin of the IX layer, during ion migration towards the bulk brine solution. 81.5% of NO3− was removed with better NO3− selectivity from real municipal wastewater, and a high concentration of NO3− brine was obtained through successive operation. However, the poorly selective NO3− desorption, which limits its enrichment due to the reverse ionic-strength gradient induced by the high concentration brine, needs to be mitigated to prove its effective recovery.
KW - Ion-exchange membrane
KW - Membrane capacitive deionization
KW - Nitrate selectivity
KW - Resource recovery
KW - Wastewater reuse
UR - http://www.scopus.com/inward/record.url?scp=85081884068&partnerID=8YFLogxK
U2 - 10.1016/j.desal.2020.114425
DO - 10.1016/j.desal.2020.114425
M3 - Article
AN - SCOPUS:85081884068
SN - 0011-9164
VL - 484
JO - Desalination
JF - Desalination
M1 - 114425
ER -