The catalytic hydrogenation of m-dinitrobenzene (m-DNB) was studied using Au catalysts supported on oxides with magnetic properties. The catalysts were characterized by magnetic susceptibility measurements, XRD, N-2 adsorption, TPR, and XPS analysis. The results showed that the gold nanoparticles supported on Fe3O4-SiO2 led to the formation of Au delta- sites. However, this type of site did not alter the catalytic behavior. The catalysts showed high activity and were easily separable. The presence of Fen+ sites prevented the formation of intermediate hydroxylamines. (C) 2013 Elsevier B.V. All rights reserved.