CO Hydrogenation to Methanol over Cu/MgO Catalysts and Their Synthesis from Amorphous Magnesian Georgeite Precursors

The synthesis of Mg-substituted copper hydroxycarbonates by constant-pH co-precipitation with subsequent ageing the precipitate has been studied in detail. This allowed retrieval crystalline magnesian malachite samples, which showed a “radical-sign-shaped” pH drop and blue/green color change during that is well-known from analogous Cu/Zn system. crystallization Cu-rich samples elaborately means powder diffraction, pair distribution function (PDF), infrared spectroscopy, thus elucidating chemistry Cu,Mg general. It was found up to 17 % Mg can be incorporated into using route comparable established for Cu/ZnO catalysts, but drastically elongated times. For higher contents, step-like observed instead, an amorphous variant hydroxycarbonate, referred as “magnesian georgeite”, could isolated. From such Mg-rich sample (Cu/Mg 70 : 30 at. %), Cu/MgO catalyst prepared shows high activity good stability CO hydrogenation methanol over 800 hrs. time on stream.