Direct synthesis of dimethyl ether (DME) from syn-gas was investigated over a series of hybrid catalytic systems containing Cu-based methanol synthesis component with varying amount of ZnO and MgO, and -Al 2 O 3 as a methanol dehydration component. Methanol synthesis and methanol dehydration components were homogeneously mixed in 2:1 weight ratio to prepare the hybrid catalysts, which were characterized by Transmission electron microscopy, Scanning electron microscopy, BET surface area analyzer, Powder X-Ray diffraction, NH 3-Temperature programmed desorption and H 2-Temperature programmed reduction methods. Syn-gas to DME (STD) reaction was studied in an isothermal fixed bed reactor at 30 bar and 260 C. The catalysis results revealed an improved effectiveness of the catalyst in the presence of 20 mol% MgO, enabling a significant enhancement in CO conversion from 19 to 37% and DME selectivity from 36 to 83%, when compared with the activity of a catalyst without MgO. By-products, CO 2 and C 1-C 2 hydrocarbons, selectivity were also decreased from 48 to 14% for CO 2 and from 8 to 2.5% for hydrocarbons. Catalyst performance, CO conversions and DME selectivity were evaluated by varying the reaction temperature, pressure, space velocity and H 2 /CO ratio in syn-gas. XRD data revealed the formation of a well crystalline malachite structure for the catalysts containing up to 20 mol% MgO, but the crystallinity in the structure lost when 30% MgO was added, resulting in a decreased catalytic activity.

A facile new method for the synthesis of nanostructured Cu2O–ZnO and Cu2O–ZnO–MgO catalysts has been described.