TY - JOUR
T1 - Arsenic removal by advanced electrocoagulation processes
T2 - The role of oxidants generated and kinetic modeling
AU - Montefalcon, Micah Flor V.
AU - Chiong, Meliton R.
AU - Resurreccion, Augustus C.
AU - Garcia-Segura, Sergi
AU - Ocon, Joey D.
N1 - Funding Information:
This research was funded by the PHIL-ECAR-I project under The Commission on Higher Education - Philippine-California Advanced Research Institutes (CHED-PCARI, IIID-2017-32).
Funding Information:
Acknowledgments: M.F.V.M. would like to acknowledge the Engineering Research and Development for Technology (ERDT) Program of the Department of Science and Technology—Science Education Institute (DOST‐ SEI) for the graduate scholarship and research grant. The authors would like to acknowledge Ashok Gadgil of the University of California Berkeley for the discussions. M.F.V.M. and J.D.O. are grateful for the help of Angelica Paz F. Kabigting, Mecaelah S. Palaganas, and Mark Joseph M. Pasciolco in the preliminary experiments.
Funding Information:
Funding: This research was funded by the PHIL‐ECAR‐I project under The Commission on Higher Education – Philippine‐California Advanced Research Institutes (CHED‐PCARI, IIID‐2017‐32).
Publisher Copyright:
© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2020/8
Y1 - 2020/8
N2 - Arsenic (As) is a naturally occurring element in the environment that poses significant risks to human health. Several treatment technologies have been successfully used in the treatment of As-contaminated waters. However, limited literature has explored advanced electrocoagulation (EC) processes for As removal. The present study evaluates the As removal performance of electrocoagulation, electrochemical peroxidation (ECP), and photo-assisted electrochemical peroxidation (PECP) technologies at circumneutral pH using electroactive iron electrodes. The influence of As speciation and the role of oxidants in As removal were investigated. We have identified the ECP process to be a promising alternative for the conventional EC with around 4-fold increase in arsenic removal capacity at a competitive cost of 0.0060 $/m3. Results also indicated that the rate of As(III) oxidation at the outset of electrochemical treatment dictates the extent of As removal. Both ECP and PECP processes reached greater than 96% As(III) conversion at 1 C/L and achieved 86% and 96% As removal at 5 C/L, respectively. Finally, the mechanism of As(III) oxidation was evaluated, and results showed that Fe(IV) is the intermediate oxidant generated in advanced EC processes, and the contribution of OH brought by UV irradiation is insignificant.
AB - Arsenic (As) is a naturally occurring element in the environment that poses significant risks to human health. Several treatment technologies have been successfully used in the treatment of As-contaminated waters. However, limited literature has explored advanced electrocoagulation (EC) processes for As removal. The present study evaluates the As removal performance of electrocoagulation, electrochemical peroxidation (ECP), and photo-assisted electrochemical peroxidation (PECP) technologies at circumneutral pH using electroactive iron electrodes. The influence of As speciation and the role of oxidants in As removal were investigated. We have identified the ECP process to be a promising alternative for the conventional EC with around 4-fold increase in arsenic removal capacity at a competitive cost of 0.0060 $/m3. Results also indicated that the rate of As(III) oxidation at the outset of electrochemical treatment dictates the extent of As removal. Both ECP and PECP processes reached greater than 96% As(III) conversion at 1 C/L and achieved 86% and 96% As removal at 5 C/L, respectively. Finally, the mechanism of As(III) oxidation was evaluated, and results showed that Fe(IV) is the intermediate oxidant generated in advanced EC processes, and the contribution of OH brought by UV irradiation is insignificant.
KW - Arsenite and arsenate removal
KW - Electrochemical peroxidation
KW - Fentonlike processes
KW - Peroxicoagulation
KW - Photo-assisted processes
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U2 - 10.3390/catal10080928
DO - 10.3390/catal10080928
M3 - Article
AN - SCOPUS:85090607542
SN - 2073-4344
VL - 10
SP - 1
EP - 16
JO - Catalysts
JF - Catalysts
IS - 8
M1 - 928
ER -