Ni or Ru supported on MgO/γ-Al2O3 pellets for the catalytic conversion of ethanol into butanol

Abstract

Ni- and Ru-based catalytic pellets supported on commercial γ-Al₂O₃ pellets modified with magnesium oxide have been prepared for application in the catalytic conversion of ethanol into butanol. MgO/γ-Al₂O₃ pellets with or without added metals have been characterized by XRD, SEM/EDX, TGA, N₂ physisorption, H₂ TPR, and CO₂ TPD in order to investigate the effect of MgO coverage and metal distribution on the surface and red-ox properties of the materials and, in turn, their effects on the catalytic performance. The conversion of ethanol into butanol has been investigated in a continuous flow reactor at 350–400 °C under diluted conditions (3% ethanol) in order to rank the different catalytic pellets and identify the best formulations and preparation procedures via a comparison with powder catalysts previously proposed in the literature with similar compositions. Results show enhanced catalytic performance for MgO-covered alumina pellets with respect to a pure MgO powder catalyst in spite of the lower MgO load. A significant further positive effect is found when Ni or Ru enters a solid solution with MgO.