Photocatalytic degradation of morphine, methamphetamine, and ketamine by illuminated TiO2 and ZnO

Methamphetamine, ketamine, and morphine, found in the influent and effluent of domestic treatment plants as well as in rivers, were selected as parent compounds in this study. This investigation examined the photocatalytic removal of methamphetamine, ketamine, and morphine, from municipal wastewater effluents using illuminated TiO2 and ZnO. HPLC-MS/MS was used to measure the concentration of these drugs during reactions. UV light of 254 nm alone is capable of destroying the drugs to some extent without the TiO2 or ZnO photocatalyst, while UV light of 365 nm must be coupled with the photocatalysts to be effective. UV light of 254 nm in the presence of 0.04 g/L of TiO2 was most effective, eliminating all three drugs within 5 min; ten times as much of ZnO were required to demonstrate comparable removal. Among the three tested drugs, morphine is most readily removed by the photocatalytic treatment.