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

Samples of Ni-doped goethites were prepared and characterized by Mossbauer spectroscopy, IV, XRD, TPR and BET surface area measurements. Mossbauer 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 O-2 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. (C) 2010 Elsevier B.V. All rights reserved.