The fabrication of BaTiO3 supported AuPd nanoparticles for selective oxidation of 1,2‐propanediol to lactic acid

Abstract

AbstractBACKGROUNDThe oxidation of 1,2‐propanediol under alkaline conditions in the presence of a heterogeneous catalyst can be tailored to the formation of lactic acid, an important commodity chemical. In the present study, BaTiO3 supported bimetallic AuPd nanoparticles was fabricated by sol‐immobilized method and investigated by different characterizations. The optimum operating parameters of 1,2‐propanediol catalytic oxidation were explored via the combination of single factor experiment and response surface methodology.RESULTSThe high lactic acid yield of 81.4% can be obtained under optimum operating conditions (106 °C, 1.1 MPa O2 pressure, and NaOH/1,2‐PDO molar ratio of 3.0). The results of single factor experiment indicated that selectivity to lactic acid decreased with prolonging the reaction time, but increasing the temperature, NaOH concentration and O2 pressure appeared to decrease the lactic acid selectivity after an initial increase. Reaction kinetics indicated that the value of Ea was 39.2 kJ·mol−1 over AuPd/BaTiO3 catalyst. After five runs, the AuPd/BaTiO3 catalyst stills retained high activity.CONCLUSIONThe AuPd/BaTiO3 catalyst exhibited a good catalytic activity for this selective oxidation while the coalescence of Au and Pd nanoparticles can enhance the selectivity to lactic acid. NaOH/1,2‐PDO molar ratio imposed an extremely comparable impact on lactic acid yield. The mutual interactions between reaction temperature and NaOH/1,2‐PDO molar ratio, as well as NaOH/1,2‐PDO molar ratio and pressure, were of vital significance. © 2021 Society of Chemical Industry (SCI).