Removal of Selected Pharmaceuticals Spiked in the Secondary Effluent of a Wastewater Treatment Plant (WWTP) by Potassium Ferrate(VI)

This study investigated the ferrate(VI) performance in the removal of pharmaceuticals spiked in the secondary effluent taken from a wastewater treatment plant (WWTP). In the raw secondary effluent samples, seven of 12 target pharmaceuticals were detected with a maximum concentration of 500.0 +/- 28.3 ng/L for ibuprofen. 70% of carbamazepine could be reduced in the raw effluent samples by fen-ate(VI) when the dose exceeded 4 mg/L. In the modified effluent samples spiked with detected target pharmaceuticals, approximately 40% of naproxen was removed, whereas other target compounds were removed less than 30%. Raising the ferrate(VI) dose improved the removal of pharmaceuticals to some extent, while acidic conditions were more preferable for drugs' reduction. The study demonstrated that ferrate(VI) can efficiently remove pharmaceuticals containing electron-rich moieties (ERMs), and the coagulation of iron(III) colloids resulted from the reduction of Fe(VI) also influenced the treatment performance.