Effect of Ni incorporation into goethite in the catalytic activity for the oxidation of nitrogen compounds in petroleum

Abstract

Samples of Ni-doped goethites were prepared and characterized by Mössbauer spectroscopy, IV, XRD, TPR and BET surface area measurements. Mössbauer data evidenced the incorporation of Ni2+ in the goethite structure, and this cation-doping caused a significant decrease of the chemical reduction temperature in the TPR process. The catalytic behavior of these Fe1−xNixOOH materials was investigated for the H2O2 decomposition to O2 and the oxidation of quinoline. The successive hydroxylation of quinoline during this oxidation strongly suggests that highly reactive hydroxyl radicals are generated during the reaction involving H2O2 on the Ni-goethite grain surface, also confirming that these materials are efficient heterogeneous Fenton catalysts.