The integration of ZVI-dehalogenation and electrochemical oxidation for the treatment of complex effluents polluted with iodinated compounds

This work evaluates the integration of dehalogenation with Zero Valent Iron (ZVI) and electrochemical oxidation (EO) for treatment urines polluted iodinated X-ray contrast media (ICM). To do this, different strategies were evaluated: pretreatment ZVI followed by EO (ZVI-EO) or electrolysis enhanced ZVI-dehalogenation (EO/ZVI). For comparison purposes, single was also performed to check best strategy. Results showed that less efficient than EO/ZVI ZVI-EO processes. Removal percentages 74.9%, 87.6% 99.5% reached after passing 13.8 Ah dm−3 at 10 mA cm−2 during EO, ZVI-EO, respectively. process favored production large amounts hydroxyl radicals in effluent through Fenton´s reaction, enhancing degradation rate iopamidol (IPM). The allowed transform up 95% IPM C17H25N3O8. Then, attained almost complete removal raw pollutant (ZVI-EO). iodine species formed end monitored, finding similar proportions organic processes, although promoted formation stable inorganic (IO3-) release I-. Total carbon lower 20% achieved, suggesting technologies employed selective target under operating conditions studied. Finally, by-products identified LC-MS chromatographic area profiles higher values EO.