Comparison of -induced AOPs ( and ) in the degradation of iopamidol: Kinetics, energy requirements and DBPs-related toxicity in sequential disinfection processes.

The -induced advanced oxidation processes (AOPs, including and ) degradation kinetics and energy requirements of iopamidol as well as DBPs-related toxicity in sequential disinfection were compared in this study. The photodegradation of iopamidol in these processes can be well described by pseudo-first-order model and the removal efficiency ranked in descending order of  >   >  >   > . The synergistic effects could be attributed to diverse radical species generated in each system. Influencing factors of oxidant dosage, intensity, solution pH and water matrixes ( , and nature organic matter) were evaluated in detail. Higher oxidant dosages and greater intensities led to bigger pseudo-first-order rate constants (K) in these processes, but the pH behaviors exhibited quite differently. The presence of , and nature organic matter posed different effects on the degradation rate. The parameter of electrical energy per order (/) was adopted to evaluate the energy requirements of the tested systems and it followed the trend of  >  >  >   >  . Pretreatment of iopamidol by and clearly enhanced the production of classical disinfection by-products (DBPs) and iodo-trihalomethanes (I-THMs) during subsequent oxidation while and exhibited almost elimination effect. From the perspective of weighted water toxicity, the risk ranking was . Among the discussed -driven AOPs, was proved to be the most cost-effective one for iopamidol removal while displayed overwhelming advantages in regulating the water toxicity associated with DBPs, especially I-THMs. The present results could provide some insights into the application of -activated AOPs technologies in tradeoffs between cost-effectiveness assessment and DBPs-related toxicity control of the disinfected waters containing iopamidol.