Study on Selective Oxidation of Glyoxal into Glyoxalic Acid over a Novel Pd/C Catalyst

A novel Pd/C catalyst with highly dispersed Pd nanoparticles was prepared by NaBH4 reducing Pd2+ anchored on the activated carbon support and used for the selective oxidation of glyoxal to glyoxylic acid.At Pd loading of 4.7%,the reaction temperature of 50℃,the air flow rate of 100 mL/min,the pH value of 7.7,the reaction time of 3.5 h,the maximum yield of glyoxylic acid reached 30%,better than those obtained on other Pd/C catalysts prepared by reducing Pd2+ with either hydrogen flow or formaldehyde aqueous solution.