Characterization of iron oxide nanocatalyst in mineralization processes

The reuse of iron oxide nanoparticles as a catalyst of organic matter in the H2O2/iron oxide mineralization process was investigated. The particle size and morphology of iron oxide particles obtained from TEM (Transmission Electron Microscopy) images and DLS (Dynamic Light Scattering) measurements, indicate the formation of a rod-like morphology with an average length of 50 ± 10 nm. An electron diffraction pattern identified the particles as either α-FeOOH or β-FeOOH. Stability of iron oxide nanoparticles in organic model compound solutions was studied as a function of pH solution and was correlated with average size. The optimal pH for maximum mineralization in the H2O2/iron oxide system was found to be 2.8. Finally, results indicated that at least seven stages of catalytic mineralization-recovery cycles can take place without a reduction in the catalytic properties of the iron oxide nanocatalyst.