TY - JOUR
T1 - Electrochemical oxidation of reverse osmosis concentrate on mixed metal oxide (MMO) titanium coated electrodes
AU - Bagastyo, Arseto Y.
AU - Radjenovic, Jelena
AU - Mu, Yang
AU - Rozendal, René A.
AU - Batstone, Damien J.
AU - Rabaey, Korneel
N1 - Funding Information:
This study was supported by the Australian Research Council (ARC Linkage Project Grant LP0989159 ), Veolia Water Australia, Water Secure, Magneto Special Anodes and the Urban Water Security Research Alliance. The authors would like to acknowledge Dr. Mary Hodge and Dr. Henry Olszowy from Queensland Health Forensic and Scientific Service for performing the chemical analyses of oxidation by-products. Arseto Bagastyo is presently also a staff member on leave at Institut Teknologi Sepuluh Nopember, Indonesia.
PY - 2011/10/15
Y1 - 2011/10/15
N2 - Reverse osmosis (RO) membranes have been successfully applied around the world for wastewater reuse applications. However, RO is a physical separation process, and besides the clean water stream (permeate) a reverse osmosis concentrate (ROC) is produced, usually representing 15-25% of the feed water flow and containing the organic and inorganic contaminants at higher concentrations. In this study, electrochemical oxidation was investigated for the treatment of ROC generated during the reclamation of municipal wastewater effluent. Using laboratory-scale two-compartment electrochemical systems, five electrode materials (i.e. titanium coated with IrO2-Ta2O5, RuO2-IrO2, Pt-IrO2, PbO2, and SnO2-Sb) were tested as anodes in batch mode experiments, using ROC from an advanced water treatment plant. The best oxidation performance was observed for Ti/Pt-IrO2 anodes, followed by the Ti/SnO2-Sb and Ti/PbO2 anodes. The effectiveness of the treatment appears to correlate with the formation of oxidants such as active chlorine (i.e. Cl2/HClO/ClO-). As a result, electro-generated chlorine led to the abundant formation of harmful by-products such as trihalomethanes (THMs) and haloacetic acids (HAAs), particularly at Ti/SnO2-Sb and Ti/Pt-IrO2 anodes. The highest concentration of total HAAs (i.e. 2.7 mg L-1) was measured for the Ti/SnO2-Sb electrode, after 0.55 Ah L-1 of supplied specific electrical charge. Irrespective of the used material, electrochemical oxidation of ROC needs to be complemented by a polishing treatment to alleviate the release of halogenated by-products.
AB - Reverse osmosis (RO) membranes have been successfully applied around the world for wastewater reuse applications. However, RO is a physical separation process, and besides the clean water stream (permeate) a reverse osmosis concentrate (ROC) is produced, usually representing 15-25% of the feed water flow and containing the organic and inorganic contaminants at higher concentrations. In this study, electrochemical oxidation was investigated for the treatment of ROC generated during the reclamation of municipal wastewater effluent. Using laboratory-scale two-compartment electrochemical systems, five electrode materials (i.e. titanium coated with IrO2-Ta2O5, RuO2-IrO2, Pt-IrO2, PbO2, and SnO2-Sb) were tested as anodes in batch mode experiments, using ROC from an advanced water treatment plant. The best oxidation performance was observed for Ti/Pt-IrO2 anodes, followed by the Ti/SnO2-Sb and Ti/PbO2 anodes. The effectiveness of the treatment appears to correlate with the formation of oxidants such as active chlorine (i.e. Cl2/HClO/ClO-). As a result, electro-generated chlorine led to the abundant formation of harmful by-products such as trihalomethanes (THMs) and haloacetic acids (HAAs), particularly at Ti/SnO2-Sb and Ti/Pt-IrO2 anodes. The highest concentration of total HAAs (i.e. 2.7 mg L-1) was measured for the Ti/SnO2-Sb electrode, after 0.55 Ah L-1 of supplied specific electrical charge. Irrespective of the used material, electrochemical oxidation of ROC needs to be complemented by a polishing treatment to alleviate the release of halogenated by-products.
KW - Anode material
KW - Electrochemical oxidation
KW - Organic pollutants
KW - Oxidation by-products
KW - Reverse osmosis concentrates
UR - http://www.scopus.com/inward/record.url?scp=80052261178&partnerID=8YFLogxK
U2 - 10.1016/j.watres.2011.06.039
DO - 10.1016/j.watres.2011.06.039
M3 - Article
C2 - 21802107
AN - SCOPUS:80052261178
SN - 0043-1354
VL - 45
SP - 4951
EP - 4959
JO - Water Research
JF - Water Research
IS - 16
ER -