Degradation of Amitriptyline by UV, UV/H2O2 and UV/Fenton Processes

The degradation rates of amitriptyline (AMT) by UV, UV/H2O2, UV/Fenton were investigated in ultrapure water in this study. The results showed that addition of H2O2 significantly enhanced the UV degradation of AMT. Approximately 100% degradation was achieved in 120 min after addition of 0.5 mM H2O2 in solution, while only 46.9% degradation was obtained without H2O2 addition. AMT degradation was enhanced with the increase of H2O2 concentrations and the decrease of initial AMT concentrations. It was also found that the alkaline pH is more favorable than the acidic and neutral condition for AMT degradation. Moreover, the effect of Fenton's reagent ((Fe2+/H2O2) on the degradation of AMT was investigated, and the results demonstrated that the UV/Fenton system was more effective than the UV/H2O2 process for AMT degradation. Under UV, UV/H2O2 and UV/Fenton processes, the degradation of AMT followed pseudo-first-order kinetics in aqueous solution. Finally, the primary degradation intermediates and end products of AMT were detected by LC/MS/MS and possible pathways under UV irradiation were analyzed.