Vapor-phase Dehydrogenation of 3-Methyl-2-butanol over Silica-supported Cu Catalyst Prepared by Mannitol-assisted Impregnation

Silica-supported Cu (Cu/SiO2) prepared by an organic additive-assisted impregnation method was employed as catalysts for the dehydrogenation of 3-methyl-2-butanol (3M2BO) to 3-methyl-2-butanone (methyl isopropyl ketone, MIPK). The utilization of organic additives, especially mannitol, during the impregnation protocol, has led to the generation of a Cu/SiO2 catalyst containing highly dispersed Cu nanoparticles, i.e., high Cu surface area (SACu). These properties contributed to the high activity of the mannitol-assisted Cu/SiO2 catalyst, in which the activity was limited only by the equilibrium nature of the reaction. The proportional relation between the formation rate of MIPK with SACu confirmed the benefits of the utilization of organic additives. In addition, the improvement of SACu of Cu/SiO2 prepared with mannitol only gave a negligible side product originating from the dehydration of 3M2BO; thus, the equilibrium MIPK yield of 99.5% was achieved even at 300 °C.