| Summary: | Pt/CeO<sub>2</sub>-ZrO<sub>2</sub>-Bi<sub>2</sub>O<sub>3</sub>-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 CeO<sub>2</sub>-ZrO<sub>2</sub>-Bi<sub>2</sub>O<sub>3</sub> improved the oxygen release and storage abilities owing to the synergistic redox reaction of Pb<sup>2+/4+</sup> and Ce<sup>3+/4+</sup>, 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 Bi<sup>3+</sup> or Pb<sup>2+/4+</sup>. 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% Ce<sub>0.60</sub>Zr<sub>0.15</sub>Bi<sub>0.20</sub>Pb<sub>0.05</sub>O<sub>2−<i>δ</i></sub>/SBA-16, which provided a hydroxypyruvic acid yield maximum of 24.6%, after the reaction for 6 h at 30 °C in atmospheric air.
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