A series of Ag/ZrO₂ catalysts were prepared by impregnation method. The catalytic performance for selective oxidation of 1,2-propylene glycol to methyl glyoxal was investigated. Under optimum reaction conditions [V(N₂)∶V(O₂)＝300∶19, n(O₂)/n(alcohol)＝1.2, LHSV＝3.2 g/(g•h) and temperature＝673 K], the conversion of 1,2-propylene glycol got to 95.7%, and the selectivity to methyl glyoxal was 55.3%, being higher than that over conventional electrolytic silver catalyst. The UV-vis DRS and XPS results indicated that the existence of large amount of Ag^＋ and Ag_n^δ＋ in Ag/ZrO₂ catalysts contributes to the enhancement of catalytic activity.

Key words: 1,2-propylene glycol, methyl glyoxal, α-hydroxyacetone, silver, zirconia, electronic state, UV-vis DRS