Base-free oxidation of glycerol using titania-supported trimetallic Au–Pd–Pt nanoparticles.

Base-free selective oxidation of glycerol has been investigated using trimetallic Au–Pd–Pt nanoparticles supported on titania and their corresponding bimetallic catalysts. Catalysts were prepared by the sol-immobilization method and characterized by means of TEM, UV/Vis spectroscopy, diffuse reflectance infrared fourier transform spectroscopy, X-ray photoelectron spectroscopy, and microwave plasma–atomic emission spectroscopy. It was found that of the bimetallic catalysts, Pd–Pt/TiO2 was the most active with high selectivity to C3 products. The addition of Au to this catalyst to form the trimetallic Au–Pd–Pt/TiO2, resulted in an increase in activity relative to Pd–Pt/TiO2. The turnover frequency increased from 210 h(−1) with the Pd–Pt/TiO2 catalyst to378 h(−1) for the trimetallic Au–Pd–Pt/TiO2 catalyst with retention of selectivity towards C3 products.