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研究含铬钒酸盐溶液分离回收钒的循环冶金工艺,工艺过程包括溶液中钒的选择性沉淀、沉淀物中钒的浸出及五氧化二钒的制备.在含铬钒酸盐溶液中加入Ca(OH)2进行球磨,不仅可以使其中的钒选择性沉淀析出,而且沉淀物的浸出动力学性能得到显著改善.在含铬钒酸盐溶液中按Ca/V摩尔比1.75:1加入Ca(OH)2,室温球磨60 min,钒的沉淀率达99.59%,而铬的沉淀率只有0.04%.过滤得到的沉钒渣按液固比4:1 mL/g加水,并按NaHCO3/V摩尔比2.74:1加入NaHCO3,室温搅拌60 min,过滤得浸出液,钒的浸出率为99.35%.所得浸出液先通入CO2调pH至8.0,再按NH4HCO3/NaVO3摩尔比1:1加入NH4HCO3,室温搅拌8 h结晶析出NH4VO3,过滤后,含氨的结晶液重新用于钒酸钙沉淀的浸出,温室搅拌1 h后钒的浸出率>99%,最后,将所得NH4VO3晶体在560℃煅烧2 h得到纯度为99.6%的V2O5.“,”The separation and recovery of V from chromium-containing vanadate solution were investigated by a cyclic metallurgical process including selective precipitation of vanadium, vanadium leaching and preparation of vanadium pentoxide. By adding Ca(OH)2 and ball milling, not only the V in the solution can be selectively precipitated, but also the leaching kinetics of the precipitate is significantly improved. The precipitation efficiency of V is 99.59% by adding Ca(OH)2 according to Ca/V molar ratio of 1.75:1 into chromium-containing vanadate solution and ball milling for 60 min at room temperature, while the content of Cr in the precipitate is 0.04%. The leaching rate of V reaches 99.35% by adding NaHCO3 into water according to NaHCO3/V molar ratio of 2.74:1 to leach V from the precipitate with L/S ratio of 4:1 mL/g and stirring for 60 min at room temperature. The crystals of NH4VO3 are obtained by adjusting the leaching solution pH to be 8.0 with CO2 and then adding NH4HCO3 according to NH4HCO3/NaVO3 molar ratio of 1:1 and stirring for 8 h at room temperature. After filtration, the crystallized solution containing ammonia is reused to leach the precipitate of calcium vanadates, and the leaching efficiency of V is >99% after stirring for 1 h at room temperature. Finally, the product of V2O5 with purity of 99.6% is obtained by calcining the crystals at 560℃ for 2 h.