Process for preparing nanometer cerium dioxide

Disclosed is a method for nano-cerium oxide preparation. The azeotropic mechanism will be introduced to the precipitation method; surfactant is added to 0.1-0.5 mol / L cerium salt solution and precipitator is rapidly added for reaction, then the gel produced after the reaction is washed by ionic water and mixed with a certain amount of organic alcohol under rapid mixing; then the mixture is poured into an azeotropic device to be slowly heated above the alcohol boiling point; through refluxing, the gel is taken out and dried to obtain precursor powder; through the baking of the precursor powder, high-purity active CeO2 is obtained. The nano-CeO2 prepared by the present invention is within 5 to 19 nm in grain size, which is smaller and more uniformly, with better dispersibility and greater activity. The organic alcohol used in the azeotropic distillation process is recyclable and is low in cost and can prevent environmental pollution.