Oxidation method for preparing benzil from benzoin

The invention relates to an oxidation method for preparing benzil from benzoin, which comprises the following steps of: introducing oxygen-containing gas serving as reaction gas into a reaction system of nitric acid and benzoin, and reacting under the pressure of 2-5Mpa, so that the amount of nitric acid required by the reaction is obviously reduced, no nitric oxide is produced in the reaction process, the nitric acid can be recycled, and the yield of the reaction is improved. The oxidation method has high benzil yield and purity, the yield can reach 98% or above, and the purity can reach 99% or above. 本发明涉及一种苯偶姻制备苯偶酰的氧化方法，所述氧化方法以含氧气的气体作为反应气体通入硝酸与苯偶姻的反应体系中，并控压在2Mpa～5Mpa的压力下进行反应，反应所需硝酸量明显降低，反应过程无氮氧化物产出，硝酸能实现循环套用，且本发明上述氧化方法具有较高的苯偶酰收率和纯度，收率可达98％以上，纯度可达99％以上。