Supported Cobalt Catalysts for Acceptorless Alcohol Dehydrogenation

SSCI-VIDE+CDFA:ECI2D+CPI:SLO:MBE:NPRInternational audienceThe acceptor-less dehydrogenation of 2-octanol was tested over Co supported on Al2O3, C, ZnO, ZrO2 and various TiO2. The catalysts were characterized by ICP, XRD and TGA-H2. For Co/TiO2 P25, the effects of passivation, aging (storage at room temperature), and in situ activation under H2 were investigated. The catalysts have to be tested shortly after synthesis, in order to prevent deactivation. Co supported onTiO2 P25 was the most active and 69% yield of 2-octanone was obtained, using decane as a solvent. Selectivity to 2-octanone in the range of 90% to 99.9% were observed. Small amounts of C16 compounds were also formed due to aldol condensation/dehydration reactions. The catalysts exhibited higher conversion for the dehydrogenation of secondary alcohol (65-69%), in comparison to primary alcohol (2-10%). The dehydrogenation of 1,2-octanediol led principally to 1-hydroxy-2-octanone, with a selectivity of 90% and 69% for Co/TiO2 P25 and Co/TiO2 P90, respectively