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The selective hydrogenolysis of bioglycerol to 1,2-propanediol was investigated over a series of Ce-promoted Cu/Mg catalysts, namely, Cu/Mg (1/9), Cu/Ce/Mg (1/1/5), Cu/Ce/Mg (1/3/5), and Cu/Ce/Mg (1/5/5) prepared by a coprecipitation method. The physicochemical properties of the synthesized catalysts were analyzed by XRD, Raman, BET, BJH, XPS, NH3- and CO2-TPD, and H2-TPR techniques. The XRD and BET surface area results indicated that addition of Ce to Cu/Mg sample remarkably inhibits the crystal growth of CuO and improves the specific surface area. More number of oxygen vacancy defects were found in the Cu/Ce3/Mg sample, as evidenced from Raman studies. The reducible nature of the Cu/Mg sample was significantly enhanced after the Ce-incorporation. The NH3- and CO2-TPD results show that the acid–base properties of the Ce-promoted Cu/Mg samples are highly dependent on the Ce-loading. Among the synthesized samples, the Cu/Ce3/Mg sample exhibited higher concentration and superior strength of acidic sites. The achieved activity order of various catalysts for glycerol hydrogenolysis is Cu/Mg

The present investigation was undertaken to know the influence of different dopants on the physicochemical properties and catalytic behavior of nano-Au/CeO2 catalyst for CO oxidation. Accordingly, various metal ions namely, Fe3+, La3+ and Zr4+ were incorporated into the ceria lattice by a facile coprecipitation approach using ultra-high dilute aqueous solutions. An anion adsorption method was used to prepare the Au/doped-CeO2 catalysts in the absence of any base, reducing and protective agents. The physicochemical characterization was performed by XRD, BET surface area, ICP-AES, TG-DTA, FT-IR, TEM, UV–vis DRS, Raman, XPS and TPD techniques. Doped CeO2 exhibited smaller crystallite size, higher BET surface area and larger amount of oxygen vacancies than the pure CeO2. These remarkable properties showed a beneficial effect toward gold particle size as confirmed by XRD and TEM studies. XPS results revealed that Au is present in the metallic state and Ce in both +3 and +4 oxidation states. Incorporation of Zr into the Au/CeO2 resulted in high CO oxidation activity attributed to the presence of more Ce3+ ions and oxygen vacancies. In contrast, the La-incorporation caused an opposite effect due to the presence of carbonate species on the surface of Au/CeO2–La2O3 catalyst, which blocked the active sites essential for CO oxidation. It was shown that accumulation of carbonate species strongly depends on the acid–base properties of the supports. The catalytic performance of Au catalysts is highly dependent on the nature of the support.