Photodegradation of dyes in aqueous solutions containing Fe(III)-oxalato complexes

The photolysis of Fe(III)-oxalato complexes can produce active oxidant H2O2 and • OH radicals, which can oxidize organic compounds in the atmospheric waters. Fe(III)-oxalato complexes and its photochemical reactions were applied to exploratory research on waste water treatment by promoting the destruction of dye molecules and the discoloration of their solutions. The photodegradation kinetics of the five dyes (C.I. reactive red 2, C.I. reactive blue 4, C.I. reactive black 8. C.I. basic red 13 and C.I. basic yellow 2) in aqueous solutions containing Fe(III)-oxalato complexes were studied. Results showed that the photodegradation reactions of the five dyes were all pseudo-first order reactions. The effects of pH, dye concentration and the ratio Fe(III)/oxalato(Fe/OX) on the photodegradation rate of the dye (C.I. reactive red 2) were also inspected.