The role of carbonate as a catalyst of Fenton-like reactions in AOP processes: CO3˙(-) as the active intermediate.

Kinetic and DFT results for the carbonate catalysed Co(H2O)6(2+) + H2O2 Fenton-like reaction suggest a mechanism involving the formation of a cyclic transient, cyclic-(CO4)Co(II)(OOH)(H2O)2(-) that decomposes into Co(II)(H2O)(OOH)(OH)2 + CO3˙(-), i.e. no OH˙ radicals are involved.

Three H₂O₂ molecules are involved in the "Fenton-like" reaction between Co(H₂O)₆²⁺ and H₂O₂.

Co(II) complexes and Co(H2O)6(2+) are used as catalysts in advanced oxidation processes. Therefore it was decided to study the kinetics of reaction of Co(H2O)6(2+) with H2O2. Surprisingly, the kinetic results point out that the process involves three consecutive reactions, each of them requiring an H2O2 molecule, i.