直接还原法处理复杂稀有金属矿新工艺

New Process of Direct Reduction to Treat Complex Rare Metal Ore

开发了一种复杂稀有金属矿"直接还原—酸化浸出—沉淀煅烧"回收稀土、铌、钽和铁的新工艺。结果表明,添加质量分数35%碱性添加剂在1 050℃还原120min,还原产物经湿式弱磁选分离获得铁品位91.62%的铁粉,铁回收率为91.03%。非磁性物采用硫酸酸化、浸出、沉淀得到REO含量93.37%的稀土氧化物,稀土总回收率74.26%。沉淀稀土后的溶液添加氨水调节溶液pH至8.5,得到铌钽沉淀,经煅烧后得到Nb(Ta)2O5含量32.65%的铌钽富集物,铌和钽回收率分别为75.44%和66.21%。

A new process composed of direct reduction,acidification and leaching,precipitation and roasting was developed to recover rare earth,niobium,tantalum and iron from a complex rare metal ore.The results show that the iron powder with 91.62％ TFe and recovery of 91.03％ is obtained when raw ore is mixed with mass fraction 35％// alkaline additive,reduced at 1 050 ℃ for 120 min,and then separated by wet low intensity magnetic separation.The rare earth oxide with 93.27％ REO and recovery of 74.26％ is gained when the nonmagnetic materials are acidized with sulfuricacid,leached and precipitated.Nb-Ta precipitation is obtained from precipitated solution at pH value of 8.5 adjusted with ammonia water.The Nb-Ta enrichment with 32.65％ Nb（Ta）2O5 is produced after the precipitation is roasted,and the recovery of niobium and tantalum is 75.44％ and 66.21％ respectively.