RuNi (8 wt.% NiO; 1.1 wt.% RuO2) catalysts on ZSM-5 + Al2O3 were tested in the hydrogenation of 1-methylnaphthalene, and the effect of the Ru precursor on their physicochemical and catalytic properties was examined. The catalysts were analyzed by XRF, N-2-sorption, TPR, H-2-chemisorption, TPD-NH3, XRD, XPS, TOF-SIMS, SEM and TEM. The order of their activity and stability: [Ru(NH3)(6)]Cl-3 similar to (NH4)(2)[RuCl6] < Ru(C5H7O2)(3) < Ru-3(CO)(12) correlates with the reducibility, metal dispersion, and atomic ratio of Ni/Al + Si on the catalyst surface. (C) 2010 Elsevier B.V. All rights reserved.