Selective Oxidation of 1,2-Propanediol to Lactic Acid over Different Supported Au, Pt and Pd Catalysts

摘要

1,2-Propanediol selective oxidation with molecular oxygen in presence of heterogeneous catalyst is one of the most nature friendly 1,2-propanediol conversion methods. This work demonstrates activity and selectivity of catalysts containing Au, Pt and Pd in a 1,2-propanediol oxidation process. The main product of catalytic oxidation of 1,2-propanediol was lactic acid, and by-products were acetic and formic acids. It was found that Au based catalysts are best for 1,2-propanediol oxidation in alkaline water solutions. The best result was achieved using the 4.8 wt% AU/Al_2O_3 catalyst: selectivity by lactic acid was 94% with 1,2-propanediol conversion 100 % (co( 1,2-propanediol) = 0.3 mol/L, P(O_2) = 6 atm, n(l,2-propanediol)/n(Au) = 500, t = 60 °C, co(NaOH)=1.5mol/L).