Formation and Catalytic Activity of Homogeneous Nucleation Iron Oxide in the Presence of Hydrogen Peroxide

This research aimed to investigate the formic acid and total iron removal capability of the fluidized bed Fenton process that produced iron oxide via homogeneous nucleation mechanism at pH 6.0. Synthetic wastewater and continuous-feed bench-scale reactors were used with the hydraulic retention time of 11.64 hours. Studied variables were Fenton reagent and formic acid. Experimental results revealed that the homogeneous-nucleation fluidized-bed Fenton process had a potential to remove organic pollutant and total iron similar to heterogeneous-nucleation fluidized-bed Fenton which has external solid media. Maximum total iron and formic acid removal efficiencies obtained under the studied conditions were 89.72% and 100%, respectively. Iron oxide obtained from the homogeneous-nucleation at pH 6.0 possessed little catalytic activity to stimulate the decomposition of hydrogen peroxide to from hydroxyl radicals. However, the amount of iron oxide formed will be much less than those of the heterogeneous-nucleation fluidized-bed Fenton since no external solid media addition is needed.