Abstract
•The mechanism of a novel advanced oxidation process patented as Galvano-Fenton is investigated experimentally and numerically.•The best fitting scenario showing 93.5% of correlation includes sulfate ions reactivity and iron complex formation.•Fe(III) represents more than 85% of iron forms.•73.63% of Fe(III) exists in the electrolyte in form of FeOH2+ complex.•The predominant regeneration pathways of Fe2 + are rather radical, activated by HO2• and O2• − .
The present paper constitutes a conjugate numerical and experimental study of a novel process patented as Galvano-Fenton, based on the association of galvanic corrosion and Fenton reaction. The study investigates the pathways of the in-situ formation and regeneration of iron species involved in electrochemical and chemical mechanisms of the Galvano-Fenton process, with the objective of understanding the kinetics mechanism and identifying the predominant reaction paths. The kinetics of Fe(III) was assessed experimentally using Fricke dosimetry, while the chemical schema evolving in the electrolyte was examined using numerical modeling, and assuming four incremental mechanistic scenarios. The mechanistic scenario accounting for sulfate ions reactivity and iron complex formation showed the highest correlation with experimental results i.e. 93.5%. It demonstrated that the +3 oxidation state iron represents 85% of iron forms, mainly as FeOH2+ complex, but also proved that predominant regeneration pathways of Fe2 + are radical, activated by HO2• and O2•−.