Degradation of chloroform by Fenton-like treatment induced by electromagnetic fields: A case of study

Abstract

The objective of this study of chloroform degradation by the first time through Fenton-like processes induced by electromagnetic fields. Fenton-like processes were carried out at natural pH with 25mg/L of H2O2 and different iron sources: i) FeCl3·6H2O (5, 50 and 100mg/L Fe3+); ii) magnetite (1g/L); iii) clay (80g/L). These treatments were driven in absence and presence of radiofrequency (RF) with an intensity of electromagnetic field of 3.68kA/m. Aqueous solution of chloroform (CHCl3) was also used to study which oxidant species are responsible for the degradation of organic matter. Because of chloroform is scavenger of primary superoxide radicals (•O2−.) and required of hydroxyl radical for their total degradation. Initial assays of ferromagnetic material/H2O2/RF processes achieved promising results in terms of DOC removal. The highest DOC removal yield (69%) in the treatment of an aqueous solution of CHCl3 was obtained by Fenton/RF treatment using 100mg/L of Fe(III) and 25mg/L of H2O2. In addition, the combination of Magnetite and Fe(III) reached notable values of CHCl3 degradation. The synergetic effect caused by the ferromagnetic properties of Magnetite and the coagulation-flocculation effect caused by iron salts at natural pH is able to reduce the organic matter in water samples. Furthermore, this treatment can be intensified by induction of RF reaching 63% of DOC removal in the CHCl3 solution.