Photodegradation of Acetaminophen in Secondary Effluent of Sewage Treatment Plant under Simulated Sunlight Irradiation

The presence of pharmaceutical compounds in surface waters is an emerging environmental issue. This study investigated the photodegradation of acetaminophen (ACTP) in secondary effluent of a sewage treatment plant (STP) under simulated sunlight irradiation. ACTP can be quickly photodegradated in STP effluents, the degradation reaction was fitted well into the first-order kinetic. Effects of pH values, ACTP initial concentration and the addition of active species, such as iron ions, nitrate ions, and humic acid (HA) were also discussed. Results showed that the photodegradation apparent rate constant (kobs) and efficiency (%) was promoted in the presence of Fe
³⁺
and nitrate, and the photodegradation was retarded in the presence of HA.