Removal of Carbamazepine in Aqueous Solution by CoS2/Fe2+/PMS Process

Carbamazepine (CBZ), as a typical pharmaceutical and personal care product (PPCP), cannot be efficiently removed by the conventional drinking water and wastewater treatment process. In this work, the CoS₂/Fe²⁺/PMS process was applied for efficient elimination of CBZ. The CBZ removal efficiency of CoS₂/Fe²⁺/PMS was 2.5 times and 23 times higher than that of CoS₂/PMS and Fe²⁺/PMS, respectively. The intensity of DMPO-HO• and DMPO-SO4•− followed the order of Fe²⁺/PMS < CoS₂/PMS < CoS₂/Fe²⁺/PMS, also suggesting the CoS₂/Fe²⁺/PMS process has the highest oxidation activity. The effects of reaction conditions (e.g., CoS₂ dosage, Fe²⁺ concentration, PMS concentration, initial CBZ concentration, pH, temperature) and water quality parameters (e.g., SO42−, NO3−, H2PO4−, Cl−, NH4+, humic acid) on the degradation of CBZ were also studied. Response surface methodology analysis was carried out to obtain the best conditions for the removal of CBZ, which are: Fe²⁺ = 70 µmol/L, PMS = 240 µmol/L, CoS₂ = 0.59 g/L. The sustainability test demonstrated that the repeated use of CoS₂ for 8 successive cycles resulted in little function decrease (<10%). These findings suggest that CoS₂/Fe²⁺/PMS may be a promising method for advanced treatment of tailwater from sewage treatment plant.