Optimization of a cell for the electrochemical synergistic production of peroxoacetic acid

Abstract

This work describes a new process for the efficient electrochemical production of peroxoacetic acid (PAA) from aqueous acetic acid solutions, coupling the cathodic production of hydrogen peroxide and the oxidation of acetic acid at the anode. The key role of the production of hydrogen peroxide in the accumulation of PAA is demonstrated, together with the importance of the anode material. Thus, boron doped diamond (BDD) anodes exhibited better performance than dimensionally stable anodes (DSA®) because of the promotion of the oxidation of acetic acid via hydroxyl radicals. Moreover, it was observed that the production yield of peroxoacetic acid increases with current density until a threshold (27 A m−2 for BDD anodes), from which decomposition of hydrogen peroxide and PAA become dominant and the efficiency of the process decreases for higher current densities. Finally, it was found that the configuration of the electrochemical cell played an unexpected key role in the performance of the process due to the dissimilar efficiency in the use of the hydrogen peroxide electrochemically produced.