Fenton oxidation of indole-3-acetic acid by iron alginate beads.

A heterogeneous Fenton reaction using Iron alginate beads (Fe-AB) was evaluated for the removal of an N-heterocyclic compound indole-3-acetic acid (IAA), which ranked as uremic toxin and an herbicide derivative. The efficiency of the process was studied as a function of the experimental conditions: initial pH; H2O2dose, temperature, initial concentrations of IAA, and Iron alginate beads loading. Under the best experimental conditions: pH 3.0; H2O2dose = 9.8 mM; and [alginate beads] = 1.0 g L−1, it was possible to remove 100% of 0.11 mM IAA in 120 min in a batch reaction at 25°C. The experimental results indicate also that the use of this catalyst allows a significant removal of total organic carbon without significant leaching of Fe ions. A kinetic analysis showed that the removal of IAA followed a first-order kinetics model. In addition, the Fe-AB catalyst can be reused for successive runs, without significant loss of activity. [ABSTRACT FROM AUTHOR]