Replacement of H2O2 by O-2 in Fenton and photo-Fenton reactions

The consumption of oxygen during the degradation of aniline by Fenton and p hoto-Fenton reactions is studied. The effect that parameters like aniline, Fe(II) and H2O2 initial concentration, pH, temperature and O-2 how rate hav e on the ratio O-2 consumed/H2O2 consumed is examined. The determination of those combinations of experimental conditions for which an effective parti al replacement of H2O2 by O-2 as electron acceptor takes place is investiga ted. The results show that this replacement takes place in a variable exten t, but the presence of H2O2 is necessary along the reaction, and the maximu m consumption of O-2 only takes place when the ratio amount of aniline mine ralized vs. initial aniline concentration is minimal. (C) 2000 Elsevier Sci ence Ltd. All rights reserved.