The MgF2-MgO system of different quantitative compositions was tested as a potential support for nickel catalysts to be used for hydrogenation of toluene. The catalytic performance of the system was studied as a function of the MgF2/MgO ratio in the support and the reaction conditions. The hydrogenation was performed at temperatures ranging from 75 to 225 degrees C on the catalysts activated in hydrogen at different temperatures (400-550 degrees C). The activities of Ni/MgF2-MgO catalysts were compared to those of Ni/MgF2, Ni/MgO and Ni/Al2O3. The highest activities were observed in the case of the catalysts supported on MgF2-MgO (containing 40 mol.% MgO), especially after the activation at 500 degrees C. The catalytic activity of nickel supported on magnesium oxo-fluoride tested in toluene hydrogenation was much higher than that of Ni supported on the commonly used supports such as Al2O3 or MgO. (C) 2012 Elsevier B.V. All rights reserved.