One-step conversion of acetone to methyl isobutyl ketone over Pd-mixed oxide catalysts prepared from novel layered double hydroxides

摘要

Novel layered double hydroxides, [MAl4(OH)(12)](NO3)(2)center dot nH(2)O (M = (Li+)(2), Co2+, Ni2+, Cu2+, Zn2+), impregnated with palladium, have proved to be precursors to active bifunctional mixed oxide catalysts for the one-step synthesis of methyl isobutyl ketone (MIBK) from acetone and H-2 in the gas phase. High acetone conversions of up to 76% and MIBK selectivities of up to 91% were recorded at a reaction temperature of 250 degrees C and atmospheric pressure. The palladium catalysts based on Li and Zn layered double hydroxides displayed efficient catalytic performances at the low reaction temperature of 120 degrees C. Powder XRD and Al-27 MAS NMR showed that initially crystalline layered double hydroxides transformed to amorphous mixed oxide materials upon catalyst activation at 250 degrees C under H-2. (c) 2008 Elsevier Inc. All rights reserved.