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 m2 g−1 and intrinsic basicities of 4–17 μmol CO2 m−2. Results revealed that methyl formate was a primary product of CH3OH decomposition, whereas CO was a secondary product. Although selectivity to C2 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 μmol CO2 m−2) at which the selectivity to C2 species and methyl formate reached a maximum. The role of catalyst basic properties in the formation of C2 species from CH3OH is discussed.

Graphical abstractThe decomposition of CH3OH has been investigated over high surface area MgO, Cu–MgO, K–Cu–MgO and Cs–Cu–MgO catalysts. At 101 kPa and 498 K, methyl formate was a primary product of CH3OH decomposition, whereas CO was a secondary product. There was an optimum intrinsic catalyst basicity at which the selectivity to C2 species and methyl formate reached a maximum.Figure optionsDownload full-size imageDownload high-quality image (39 K)Download as PowerPoint slide