Properties of alkali-promoted Cu-MgO catalysts and their activity for methanol decomposition and C2-oxygenate formation

The decomposition of CH3OH in the presence of CO has been investigated over high surface area MgO, Cu-MgO, K-Cu-MgO and Cs-Cu-MgO catalysts. The catalysts were prepared by thermal decomposition of metal salts mixed with palmitic acid. The reduced catalysts had surface areas of 18-74 m(2) g(-1) and intrinsic basicities of 4-17 mu mol CO2 m(-2). Results revealed that methyl formate was a primary product of CH3OH decomposition, whereas CO was a secondary product. Although selectivity to C-2 species (ethanol and acetic acid) was low (<5 C-atom %) at the low pressure (101 kPa) conditions of the present study, there was an optimum intrinsic basicity (9.5 mu mol CO2 m(-2)) at which the selectivity to C-2 species and methyl formate reached a maximum. The role of catalyst basic properties in the formation of C-2 species from CH3OH is discussed. (c) 2010 Elsevier BM. All rights reserved.