A series of Cu/MCM-48 catalysts is studied for the liquid phase hydrogenation of crotonaldehyde. Copper is incorporated in MCM-48 following a classical hydrothermal synthesis or by wet impregnation of the MCM-48 precursor (before eliminating the directing agent) with Cu(AcAc)(2). The copper loading is in the 2-20 wt% range. Characterization results from TPR and XRD indicate that copper crystals supported on MCM-48 surface coexist with copper incorporated in the MCM-48 walls. The presence of Cu+ in MCM-48 is concluded from characterization with FTIR of adsorbed CO. This species would be the responsible for the relatively high selectivity of Cu/MCM-48. These catalysts show approximately 50% of selectivity against 7% of Cu/SiO2 (both values measured at 10% of conversion). (C) 2012 Elsevier B.V. All rights reserved.