TY - JOUR
T1 - Flow-electrode capacitive deionization for enhanced selective separation of ammonia, phosphorus, and caproate from sewage sludge fermentation
T2 - Performance and mechanistic insights
AU - Sun, Huimin
AU - Wang, Pengyao
AU - Zhang, Xuedong
AU - Wu, Bo
AU - Cui, Minhua
AU - Liu, Hongbo
AU - Ersahin, Mustafa Evren
AU - Ozgun, Hale
AU - Liu, He
N1 - Publisher Copyright:
© 2025 Elsevier Ltd
PY - 2025/3
Y1 - 2025/3
N2 - Caproic acid has broad applications and can be produced from activated sludge via fermentation, but its quality is hindered by ammonia (NH4+-N) and reactive phosphorus (RP) in the fermentation broth. However, flow-electrode capacitive deionization (FCDI), a novel ion separation technology that operates continuously without secondary pollution seems to be an efficient process that separates the ions. The results showed that at pH 5.0, the majority of N and P presented as NH4+ and H2PO4-, with removal efficiencies of 59.5 % for NH4+-N, 49.5 % for RP, and 17.4 % for caproate. Higher caproate concentrations increased boundary layer thickness, thereby promoting caproate transport to compensate for the ions consumed. The anion exchange membrane exhibited stronger rejection of divalent phosphate than acetate and caproate, resulting in lower HPO42− selectivity. The FCDI holds potential as a viable technology for resource recovery from fermentation broth, offering an alternative method in bioprocessing applications.
AB - Caproic acid has broad applications and can be produced from activated sludge via fermentation, but its quality is hindered by ammonia (NH4+-N) and reactive phosphorus (RP) in the fermentation broth. However, flow-electrode capacitive deionization (FCDI), a novel ion separation technology that operates continuously without secondary pollution seems to be an efficient process that separates the ions. The results showed that at pH 5.0, the majority of N and P presented as NH4+ and H2PO4-, with removal efficiencies of 59.5 % for NH4+-N, 49.5 % for RP, and 17.4 % for caproate. Higher caproate concentrations increased boundary layer thickness, thereby promoting caproate transport to compensate for the ions consumed. The anion exchange membrane exhibited stronger rejection of divalent phosphate than acetate and caproate, resulting in lower HPO42− selectivity. The FCDI holds potential as a viable technology for resource recovery from fermentation broth, offering an alternative method in bioprocessing applications.
KW - Caproate concentration
KW - CFD simulation
KW - Continuous operation
KW - Electrochemical process
KW - Ionic competition
UR - http://www.scopus.com/inward/record.url?scp=85214340906&partnerID=8YFLogxK
U2 - 10.1016/j.biortech.2025.132048
DO - 10.1016/j.biortech.2025.132048
M3 - Article
AN - SCOPUS:85214340906
SN - 0960-8524
VL - 419
JO - Bioresource Technology
JF - Bioresource Technology
M1 - 132048
ER -