Disinfection of water inoculated with Enterococcus faecalis using solar/Fe(III)EDDS-H2O2 or S2O82− process

The reactivity of hydroxyl radicals seems to be more efficient for the inactivation of such strain than the reactivity of sulfate radicals. Moreover, experimental results show that the concentration of Fe(III)EDDS complex is a key parameter for the inactivation of microrganisms. For the direct application in natural waters, the efficiency of the process in the presence of ubiquitous inorganic compounds, such as carbonate (HCO3−/CO32−) and chloride ions (Cl−), was also investigated. Carbonates showed a strong reduction on the E. faecalis inactivation in all cases; meanwhile chloride ions enhanced the inactivation in the presence of persulfate as also shown by using a complementary kinetic modeling approach. A dual role of Fe(III)EDDS complex was established and discussed; essential for the generation of radical species but a trap for the reactivity of these same radicals.