The invention relates to a preparation method of
ytterbium oxide with specific
granularity and specific surface area, and belongs to the technical field of
rare earth oxide preparation. The preparation method comprises the following steps: preparing
oxalic acid into an
oxalic acid solution with the
mass fraction of 5-15wt%; preparing
ytterbium chloride into an
ytterbium chloride solution with the concentration of 0.2-1.0 mol / L; a
polyvinyl alcohol dispersing agent solution with the
mass fraction of 0.8-1.5 wt% is added into the
ytterbium chloride solution, the adding amount of the
polyvinyl alcohol dispersing agent solution is 2-4% of the
mass of the
ytterbium chloride solution, and
ytterbium chloride mixed liquid is obtained;
warm water is added into a reaction kettle, the ytterbium
chloride mixed solution is continuously added along with stirring operation, and then the
oxalic acid solution is continuously added; and directly carrying out vacuum
filtration without aging, collecting a
filter cake, and calcining to obtain a finished product. By optimizing the using amount of the dispersing agent and the
precipitation process and accurately controlling process parameters, the obtained product is stable in performance, uniform in
particle size distribution, small in specific surface area deviation and good in reproducibility.