川西稀土矿泥预处理除锰及回收稀土

Pretreatment for Removing Mn and Recovering RE from Rare Earth Mine Mud

四川冕宁稀土矿泥中含有３ ％ ～７ ％ Ｒ Ｅ 及２ ％ ～１０ ％ Ｍｎ 。稀土赋存于矿泥锰铁非晶质体中， 为了提出该矿泥中的稀土， 必须破坏锰铁非晶态结构。本研究是采用 Ｎａ２ Ｓ Ｏ３作还原剂， 还原浸出稀土矿泥中的锰， 然后， 回收矿泥中的稀土。稀土矿泥用 Ｎａ２ Ｓ Ｏ３ 处理后， 浸出渣经氯化焙烧， 稀土回收率达７５６ ％ ， 比矿泥直接氯化焙烧的稀土回收率提高约２０ ％ 。

Abstract: The rare earth mine mud from western sichuang contains about 3%～7% RE and 2%～10% Mn, in which RE exists in Mn Fe amorphous bodies of the mud. For recovering RE in the mud, it is necessary to destroy the Mn Fe amorphous structure. Na 2SO 3 was used as reducing leaching agent to leach Mn in the mud, the suitable conditions were determined in this work. At the conditions of Na 2SO 3/mud=2∶10, leaching time 24 h, M H 2SO 4 / M Na 2SO 3 =0.7～1.0 and S/L ratio 1∶4, the recovery of Mn can reach above 90%. The mud treated by Na 2SO 3 is further roasted by chloride. RE recovery reaches to 75.6%, which is 20% higher than with the original mud.