从电解锰阳极泥中两段浸出锰富集硒试验研究

Two-stage Leaching of Manganese and Enrichment of Selenium From Electrolytic Manganese Anode Slime

研究了以蔗髓和铁粉为还原剂,在酸性条件下从电解锰阳极泥中两段浸出锰并富集硒,考察了浸出温度、浸出时间、硫酸浓度、蔗髓用量、铁粉加入量对锰、硒浸出率和浸出液中残余有机物浓度的影响。结果表明:第1浸出阶段,在蔗髓/阳极泥质量比0.075 g/g、硫酸浓度4.4 mol/L、浸出温度90℃、浸出时间3 h条件下,锰、硒浸出率分别为74.31%和43.56%,浸出液中COD质量浓度0.337 g/L;在第2浸出阶段,阳极泥中未被浸出的锰,按铁粉/阳极泥质量比0.09 g/g添加铁粉,继续还原浸出,铁粉在还原浸出锰的同时,将溶液中的硒还原为单质硒沉淀,锰浸出率达99.31%,而硒的最终浸出率仅为0.50%,富集在浸出渣中。

Two-stage leaching of manganese and enrichment of selenium from electrolytic manganese anode slime using bagasse pith and iron powder as reducing agent were studied.The effects of temperature,leaching time,sulfuric acid concentration,dosage of bagasse pith and iron powder on leaching of manganese and selenium and concentration of residual organics in the leaching solution were examined.The results show that in the first leaching stage,under the conditions of bagasse pith mass/anode mud mass of 0.075 g/g,sulfuric acid concentration of 4.4 mol/L,leaching temperature of 90℃and leaching time of 3 h,the leaching rates of manganese and selenium are 74.31%and 43.56%,respectively,and the mass concentration of COD in the leaching solution is 0.337 g/L.In the second leaching stage,the unleached manganese in the anode mud is reductive leached by adding iron powder according to iron powder mass/anode mud mass of 0.09 g/g.While manganese is reductive leached by iron powder,the selenium in the solution is reduced as elemental selenium,so that the leaching rate of manganese is 99.31%,while the final leaching rate of selenium is only 0.50%.