Preparation method of superfine dysprosium oxide with controllable specific surface area

The invention discloses a preparation method of superfine dysprosium oxide with a controllable specific surface area, and belongs to the field of rare earth material preparation. The preparation method comprises the following steps: mixing a formaldehyde aqueous solution, melamine and urotropine, adjusting the pH value, and heating for reaction to obtain a prepolymer solution; adding a dysprosium nitrate solution and an ethanol solution of cetyltrimethylammonium bromide into a stirring reaction bottle, adjusting the pH value to 6 +/-0.5, and heating to 50-70 DEG C; and simultaneously dropwise adding a sodium carbonate solution and the prepolymer solution into a stirring reaction flask, stirring for reaction, aging at room temperature to obtain a melamine resin-dysprosium carbonate precipitate, and then filtering, washing, drying and calcining to obtain the superfine dysprosium oxide. The dysprosium oxide with different specific surface areas under the same dysprosium oxide size is prepared by controlling the