Method for preparing vanadium oxide by reducing sodium vanadate zinc powder and recycling water

The invention discloses a method for preparing vanadium oxide by reducing sodium vanadate zinc powder and recycling water, which comprises the following steps: a, heating a sodium vanadate solution to 40-60 DEG C, adding zinc powder, introducing carbon dioxide during stirring to adjust the pH value, carrying out solid-liquid separation after reduction reaction to obtain a vanadium-zinc mixed precipitate and filtrate, and directly recycling the filtrate for leaching vanadium-containing clinker, the adding amount of the zinc powder is 0.9-0.96 times of the theoretical amount of reducing V < 5 + > into V < 4 + >; b, pulping the vanadium-zinc mixed precipitate, adjusting the pH value of the slurry by using sulfuric acid, fully stirring and dissolving, and then carrying out solid-liquid separation to obtain a tetravalent vanadium precipitate and a zinc sulfate solution; and c, the tetravalent vanadium precipitate is subjected to oxidation calcination treatment to prepare vanadium pentoxide, a zinc sulfate solution