The separation and recovery of chromium from solution after vanadium precipitation were investigated by deep removal of vanadium, hydrolysis precipitation of chromium, and preparation of chromium oxide. Hydrous oxide of trivalent iron is an effective deep vanadium remover and can be recycled. Under the most suitable conditions including hydrous oxide of trivalent iron addition with a Fe/V molar ratio of 4, reaction temperature of 60 °C, reaction time of 10 min, as well as the solution pH value of 3.0, the removal of vanadium reached 97.4%. Cr 3+ and Mn 2+ in solution can be separated through precipitation method. Under the conditions including solution pH value of 6.0, reaction temperature of 35 °C, and reaction time of 2 h, the precipitation of chromium was 96.6%. After deep remove manganese using sodium thiosulfate as the reducing agent, the well-crystallized Cr 2 O 3 product with a purity of 99.1% was prepared. The manganese in the solution after chromium recovery can be recycled as an oxidant by hydrolysis precipitation and hydrogen peroxide oxidation.

中文翻译：

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钒沉淀后溶液中铬的分离回收

通过深度脱钒、水解沉淀铬和制备氧化铬，研究了钒沉淀后溶液中铬的分离回收。三价铁的水合氧化物是一种有效的深钒去除剂，可以回收利用。在Fe/V摩尔比为4的三价铁水合氧化物加成、反应温度60℃、反应时间10min、溶液pH值为3.0的最适宜条件下，钒的去除达到97.4%。溶液中的Cr 3+ 和Mn 2+ 可用沉淀法分离。在溶液pH值为6.0、反应温度为35℃、反应时间为2h的条件下，铬的沉淀率为96.6%。以硫代硫酸钠为还原剂深度除锰后，制备出纯度为99.1%、结晶良好的Cr 2 O 3 产品。回收铬后溶液中的锰可通过水解沉淀和双氧水氧化作为氧化剂循环使用。