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The effects of the Bi 3+ introduction and the oxygen release and storage abilities on selective oxidation of glycerol into dihydroxyacetone (DHA) were demonstrated using Pt/CeO 2-ZrO 2-Bi 2 O 3-SnO 2 /SBA-16 (SBA-16: Santa Barbara Amorphous No. 16) catalysts. By introducing Bi 3+ or Sn 4+/2+ ions into the CeO 2-ZrO 2 promoter, the oxygen release and storage abilities were enhanced, which led to increased glycerol conversion. The improvement in the DHA yield was affected by the introduction of Bi 3+ , which might accelerate selective oxidation of a secondary hydroxy group in glycerol caused by the geometric effect. The highest activity was obtained for Pt/Ce 0.64 Zr 0.16 Bi 0.15 Sn 0.05 O 2−δ /SBA-16, which showed high oxygen release and storage abilities and a high number of Bi 3+ ions, with the DHA yield increasing to 53% and high rates of glycerol conversion (74%) and DHA selectivity (72%) after reaction at a moderate temperature of 30°C for 4 h in atmospheric air.

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Pt/CeO2-ZrO2-Bi2O3-PbO/SBA-16 (SBA-16: Santa Barbara Amorphous No. 16) catalysts were synthesized to produce hydroxypyruvic acid by glycerol oxidation. In the catalysts, the introduction of PbO into CeO2-ZrO2-Bi2O3 improved the oxygen release and storage abilities owing to the synergistic redox reaction of Pb2+/4+ and Ce3+/4+, which facilitated the oxidation ability of Pt. In addition, the oxidation of the secondary OH group in glycerol might be accelerated by the geometric effects of glycerol, Pt, and Bi3+ or Pb2+/4+. Furthermore, the moderate reaction conditions such as room temperature and open-air atmosphere enabled the suppression of further oxidation of hydroxypyruvic acid. The highest catalytic activity was obtained for 7 wt% Pt/16 wt% Ce0.60Zr0.15Bi0.20Pb0.05O2−δ/SBA-16, which provided a hydroxypyruvic acid yield maximum of 24.6%, after the reaction for 6 h at 30 °C in atmospheric air.