1 Enhancement of the 1-butanol productivity in the ethanol condensation catalyzed by noble metal nanoparticles supported on Mg-Al mixed oxide Jorge Quesada, Laura Faba, Eva Díaz, and Salvador Ordóñez* Department of Chemical and Environmental Engineering, University of Oviedo (Faculty of Chemistry), Julián Clavería s/n, 33006 Oviedo, Spain *Corresponding Author: E-mail address: sordonez@uniovi.es (S. Ordóñez) Abstract: The role of the addition of a noble metal (Ru and Pd) on the surface of a basic mixed oxide (MgAl) used as ethanol condensation catalyst is studied in this work. The activity trends for all the reaction steps (dehydrogenation, condensation, dehydration, and hydrogenation) were analyzed, concluding that dehydrogenation step is the rate-determining one under inert conditions whereas hydrogenations also take a relevant role under reducing conditions. Ruthenium has shown very promising 1-butanol productivities at soft conditions (15 times higher than the parent material) whereas palladium performance is limited by the lateral decarbonylation reaction, and its high hydrogenation activity is only determining at temperatures higher than 650 K. Keywords: Guerbet reaction; butanol; alcohol dehydrogenation; aldol condensation; bifunctional catalyst