Acetone hydrogenation over co-precipitated Ni/Al2O3, Co/Al2O3 and Fe/Al2O3 catalysts
Abstract
Co-precipitated Ni/Al2O3, Co/Al2O3 and Fe/Al2O3 catalysts containing 10–50 wt.% of metal are prepared and characterized by BET surface area, pore volume and XRD. Hydrogen chemisorption and oxygen uptake measurements are used to estimate the extent of reduction and the available surface metal sites. Acetone hydrogenation under vapour phase conditions is carried out over the catalysts in the temperature region 373–523 K. Conversion and selectivity of the catalysts are compared and are correlated with their hydrogen and oxygen uptake characteristics. Nickel catalysts are very active followed by cobalt and iron. A dual function mechanism involving both metal and acidic properties decide the selectivity of the products. The selectivity for propan-2-ol depends only on the metal availability whereas the selectivity for isobutyl methyl ketone depends on both acidic and metallic character of the catalyst. A mechanism explaining the different products formed is postulated.