Effects of pH and substituted 1,2-dihydroxybenzenes on the reaction pathway of Fenton-like systems

[Display omitted] •Speciation of iron complexes with different 1,2-DHB was determined.•The oxidation of dyes by Fenton-like systems driven by 1,2-DHB was evaluated.•Hammett equation was used to evaluate the effect of the substituents on 1,2-DHB.•OH was produced only at acidic pH Fenton-like systems driven by 1,2-DHB.•Fe(IV) specie was produced at neutral pH in Fenton-like systems driven by 1,2-DHB. The Fenton reaction is a redox cycle in which iron reacts with H2O2 to produce several reactive species, such as hydroxyl radicals (OH), perhydroxyl radicals (OOH), ferryl ions (Fe(IV)) and singlet oxygen (1O2). The type and amount of reactive species produced by this redox system can change depending on the reaction conditions. For example, ligands, such as 1,2-dihydroxybenzene (1,2-DHB), can promote the Fenton reaction primarily by promoting the availability of Fe(II) to react with H2O2.