SiO2-, Cu-, and Ni-supported Au nanoparticles for selective glycerol oxidation in the liquid phase

• Nano-Au was transferred from the SiO2 carrier to the Cu and Ni and fumed f-SiO2 by digestion.
• SEM, TEM, HRTEM, and XPS analyses proved the Au transfer to the prepared Au/Ni, Cu system.
• Au/SiO2 (Cu or Ni) was a highly efficient and selective catalyst in glycerol oxidation.
• Acetic acid was the main product of glycerol oxidation on Au/SiO2.

We tested for the first time the efficiency of SiO2-, Cu-, and Ni-supported Au in deep glycerol oxidation in a diluted and viscous H2O2/H2O liquid phase. Acetic acid (AA), the C2 oxidate, was preferentially formed in such a system. High conversion (100%) and AA yields (90%) were observed for the sol–gel SiO2-supported Au in diluted solutions. Although with the increase of glycerol concentration in the viscous liquid phase these values decreased to ca. 40% (conversion) and 20% (AA yield), the addition of acetonitrile improved the AA yield to ca. 40%, while the surfactants were found to be capable of a many-fold enhancement of the catalyst activity at the room temperature highly viscous liquid phase. High performances were also observed for the bimetallic Au/Cu and Au/Ni catalysts obtained by nano-Au transfer; however, these catalysts were destroyed during the reaction by the Cu or Ni leaching effect.

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