Manmade emergent contaminants are posing a big treat to the environment and human health. Their accumulation in water resources threatens the ecosystem equilibrium and challenges the current technologies to produce safe drinking water. This research explores anode oxidation (AO) using a Magnéli phase reactive electrochemical membrane (REM) flowthrough reactor as an alternative to treat reverse osmosis concentrate (ROC) water containing a broad list of organic micropollutants (OMPs). ROC water produced in two drinking water treatment facilities in the Netherlands was used to test the technology. This study searches for insights to manage ROC waste containing recalcitrant OMPs and safely discharge effluent to surface water.

Throughout laboratory experimentation, the effectivity of degrading OMPs (per-polyfluoroalkyl substances, pharmaceuticals, corrosion inhibitors, and synthetic dyes) was investigated.
Main findings suggest that 100 mg/L Methylene blue (MB) spiked in an artificial water matrix is completely mineralized after an applied charge dosage (CD) of 22.56 kC/L. Additionally, pharmaceuticals spiked in artificial water matrix and ROC were degraded above 80% after applying a charge dosage of 5.64 kC/L. Finally, PFOA and PFOS degradation for drinking water utilities 1 & 2 resulted in an average of 49.5 and 76.90 % respectively after applying 120 kC/L.

Moreover, it was found that hardness in water inhibits the degradation capacity reducing the effective area of the anode with scaling deposition. Besides, the calcium and magnesium content slightly increases the energy consumption and the frequency of chemical cleaning required to maintain the reactor. The Magneli REM reactor has capabilities to degrade OMPs when treating ROC. Operational parameters such as flowrate, and CD can be adjusted to obtain better degradation rates. However, the treated water could contain byproducts with recalcitrant properties and high toxicity (for instance, ultra and, short chain PFAS, bromate, chlorates and perchlorates). For that reason, monitoring and further treatment is recommended to safely discharge back to surface water.