分级化学沉淀法从酸性矿山废水中回收稀土元素试验研究  

Recovery of Rare Earth Elements from Acid Mine Drainage Using Staged Chemical Precipitation

作　　者：谢义曦 吴攀[2,3] 李学先 黄家琰 陈雪[1] Xie Yixi;Wu Pan;Li Xuexian;Huang Jiayan;Chen Xue(College of Agriculture,Guizhou University,Guiyang 550025,China;College of Resources and Environmental Engineering,Guizhou University,Guiyang 5500253,China;Key Laboratory of Karst Geological Resources and Environment,Ministry of Education,Guiyang 550025,China)

机构地区：[1]贵州大学农学院,贵州贵阳550025 [2]贵州大学资源与环境工程学院,贵州贵阳550025 [3]喀斯特地质资源与环境教育部重点实验室,贵州贵阳550025

出　　处：《中国稀土学报》2024年第2期360-370,I0006,共12页Journal of the Chinese Society of Rare Earths

基　　金：贵州省科技计划项目(黔科合支撑[2021]一般466);贵州省高层次人才培养计划项目(黔科合平台人才[2016]5664);贵州大学培育项目(贵大培育[2020]30号)资助。

摘　　要：酸性矿山废水(AMD)因含有较高浓度的溶解稀土元素(REY)而倍受关注,从AMD中回收REY是极具潜力的稀土补充来源。为探究从AMD中回收REY的可行性,本研究从贵州某废弃煤矿井采集REY含量为29.8×10^(-6)的AMD作为原料,采用分级化学沉淀-酸溶解-草酸选择性沉淀法回收AMD中的REY。试验结果表明,以NaOH作为pH调节剂,在去除AMD中99.8%的Fe^(3+)和67.1%的Al^(3+)等主要污染离子后,获得高度富集REY(含量约1.0%)的沉淀物。沉淀物经HNO_(3)溶解后得到富含REY的预浓缩液,加入草酸溶液,最优pH为2时,回收了浓缩液中95%的REY。将最终产物煅烧氧化后得到纯度为97%的稀土氧化物。Acid mine drainage(AMD)is of great interest because of its high concentration of dissolved rare earth elements and yttrium(REY),and the recovery of REY from AMD is a potential source of rare earth replenishment.To investigate the feasibility of recovering REY from AMD,AMD with REY content of 29.8×10^(-6) was collected from an abandoned coal mine shaft in Guizhou as raw material in this study,and a graded chemical precipitation-acid dissolution-oxalic acid selective precipitation method was used to recover REY from AMD.experimental results show that using Na0H as pH adjuster after removing 99.8%of Fe^(3+)and 67.1%of A1^(3+)and other major contaminating ions from AMD,a highly enriched precipitate(about 1.0%content)of REY was obtained.The precipitate was dissolved by HNO_(3)to obtain a REY-rich preconcent rate,and 95%of the REY in the concentrate was recovered by adding oxalic acid solution at an optimal pH of 2.The final product was calcined and oxidized to obtain rare earth oxides with a purity of 97%.

关 键 词：酸性矿山废水 稀土元素 分级化学沉淀 稀土回收 

分 类 号：TF845[冶金工程—有色金属冶金]