Dehydrogenation and condensation in catalytic conversion of iso-propanol over CuO/MgO system doped with Li2O and ZrO2

The effects of Li2O and ZrO2-doping on the surface and catalytic properties of CuO/MgO system have been investigated. The dopant concentration was changed between 0.6 and 3.6 mol% Li2O and that of ZrO2 between 2.4-7.7 mol%. Pure and variously doped solids were calcined at 673 and 773 K. The techniques employed for characterization of different solids were XRD, nitrogen adsorption at 77 K and catalytic conversion of iso-propanol at different reaction temperatures ranged between 423 and 573 K. The results revealed that the addition increasing amounts of dopant (Li2O and ZrO2) to CuO/MgO Solid led to an increase in the degree of dispersion of CuO phase and a decrease in the specific surface areas of the investigated solids. Li2O and ZrO2-doping increases the, catalytic conversion of iso-propanol, which proceeds mainly via dehydrogenation to give acetone and aldol condensation of the produced acetone to give methyl isobutyl ketone (MIBK). Doping with 1.2 mol% Li2O for the solids calcined at 673 K increases both of total conversion and selectivity to MIBK at reaction temperature 473 K with 24% and 25%, respectively. Doping with 7.7 mol% ZrO2 for the investigated solids calcined at 673 K increases both of total conversion and selectivity to MIBK at reaction temperature 473 K with 32% and 99%, respectively. (c) 2005 Elsevier B.V. All rights reserved.