The selected amount of Fe-Ce-O
70/30 and the pre calculated volume of hydrogen peroxide (50%,
w/w) were added, and the reaction began. Samples were
periodically withdrawn, filtrated to remove the catalyst, and
alkalinized to quench the remaining H2O2, which interferes with
the analytical techniques. The chemical regime was ensured
using catalyst particles with diameters in the range 250-500
μm and a stirring speed of 600 rpm.