电解锰阳极液锰镁组元选择性分离实验研究

Experimental Research on Selective Precipitation of Manganese and Magnesium in Electrolytic Manganese Anode Solution

为降低电解锰生产工序中杂质镁带来的危害,对电解锰阳极液中锰、镁的选择性分离进行了理论分析,并通过实验研究了不同条件下锰、镁分离效果。结果表明,通过碳酸盐沉淀的方式可以实现先沉锰、后沉镁的选择性分离。合适的沉锰条件为:溶液体系pH值8左右、碳酸氢铵与溶液中锰离子物质的量比1.25、反应温度38℃、反应时间30 min,沉锰后溶液中锰离子浓度可降至0.56 g/L,沉锰率达到96.34%;合适的沉镁条件为:沉锰后滤液pH值8以上、碳酸氢铵与溶液中镁离子物质的量比2.44、反应温度20℃、反应时间30 min,沉镁后溶液中镁离子浓度可减至2.33 g/L,沉镁率达到94.63%。

In order to reduce the harm brought by magnesium impurity in the production process of electrolytic manganese,selective precipitation of manganese and magnesium in electrolytic manganese anode solution was theoretically analyzed,and the precipitation effect of manganese and magnesium under different conditions were also explored by performing experiments.The results show that selective precipitation of manganese and magnesium can be realized by carbonate precipitation.It is found that under the following precipitation conditions,including solution system with pH around 8,ammonium bicarbonate and manganese ions in the solution in a molar ratio of 1.25,reaction temperature of 38℃and reaction time of 30 min,the concentration of manganese ions in the solution after manganese precipitation can be reduced to 0.56 g/L,and the precipitation rate of manganese can reach 96.34%.And then with pH value more than 8 for the filtrate after manganese precipitation,ammonium bicarbonate and magnesium ion in the solution in a molar ratio of 2.44,reaction temperature of 20℃and reaction time of about 30 min,the magnesium ion concentration in the solution after magnesium precipitation can be reduced to about 2.33 g/L,and the magnesium precipitation rate can reach 94.63%.