In the present work, the chlorination of nickel-containing materials is proposed: using NiO and mixtures that simulate the conditions of 12 wt % NiO-Al2O3 catalyst, prepared by mechanical mixing and incipient wetness impregnation (IWI), the reaction with gaseous chlorine proceeds from 500 to 800 degrees C. Non-isothermal experiments from 20 to 950 degrees C and isothermal measurements at 725, 800, and 850 degrees C were performed under Ar-Cl-2 atmosphere in a thermogravimetric (TG) system. Direct chlorination of the mixtures was carried out isothermally in a tubular reactor under a flow of Cl-2 front 500 to 800 degrees C. The chlorination started at 725, 473, and 428 degrees C for NiO, the mechanical mixture, and the IWI mixture, respectively. The high temperature for NiO call be explained by its BET area, which is small enough to reduce the reactivity of the sample. The recovery factor of Ni from Al2O3 attained at 800 degrees C was 85% for the mechanical Mixture and 96% for the IWI mixture. All the species were characterized by X-ray diffraction (XRD), scanning-electron microscopy (SEM), and energy-dispersive spectroscopy (EDS) techniques. They were quantified by X-ray fluorescence spectrometry (XRF), and BET surface area (BET) was measured in the samples.