The invention relates to the field of
chemical industry, and discloses a method for preparing high-purity
vanadium oxide by purifying
ammonium vanadate, which comprises the following steps: adding a
carbonate solution into
ammonium vanadate, stirring, and heating to 75-95 DEG C to obtain a
vanadium-containing return solution; keeping the temperature of the
vanadium-containing return solution, and adding a
calcium salt
impurity removal agent to obtain a vanadium-containing purified solution and first-stage
impurity removal
slag;
oxalate is added into the vanadium-containing purified liquid, the temperature of the vanadium liquid is kept, and deeply-purified vanadium liquid and second-stage
impurity removal
slag are obtained; cooling the deeply purified vanadium liquid to 5-35 DEG C, stirring and reacting, and then carrying out
solid-liquid separation to obtain
ammonium metavanadate and secondary vanadium
precipitation supernatant; adding pure water into the
ammonium metavanadate product, pulping, stirring, and heating to 80-95 DEG C to obtain a secondary return solution; the pH of the secondary return solution is adjusted to 1.6-2.0, the temperature is raised to 95-98 DEG C, and ammonium polyvanadate and a third-section vanadium
precipitation supernatant are obtained; and
drying the ammonium polyvanadate, raising the temperature to 500-600 DEG C in an oxidizing
atmosphere, and carrying out heat preservation and
calcination to obtain a vanadium
pentoxide product. The method can be used for preparing a high-purity vanadium
pentoxide product.