FeSO4·7H2O optimisation of earthed atomising corona discharge (Fe-EACD) a process for the pharmaceutical wastewater treatment.

Pharmaceutical residues can cause serious water pollution problems, harm human health and destroy the ecological balance. FeSO₄·7H₂O optimisation of the earthed atomising corona discharge (Fe-EACD) process was used to dispose of pharmaceutical wastewater in this research. Experiments were analyzed by VI characteristic curves to optimise the electrode distance (20–50 mm) and wire electrode diameter (0.3–0.5 mm). The effects of discharging voltage (7–12 kV), time (0–54 min) and FeSO₄ dosage (0.2–1.2 g/L) were investigated using the response surface methodology (RSM). According to the RSM results, the best removal efficiency of COD (89.6%) was detected at the optimal discharging voltage of 12 kV, time of 42 min and Fe²⁺ concentration of 0.4 g/L. The Fe-EACD process could work efficiently with BOD₅/COD ratio moving to 0.49 in an acid environment. The kinetic analysis and mechanism study suggested that the Fe-EACD process was demonstrated well by the pseudo-first-order based on the correlation coefficient (R²). Active •OH producing in the EACD process is responsible for the COD removal and the FeSO₄·7H₂O as a catalyst can promote the formation of active hydroxyl. In other words, EACD with Fe²⁺ optimisation was an economic and feasible process for pharmaceutical wastewater treatment. [ABSTRACT FROM AUTHOR]