碱溶脱硅联用机械化学提取法回收高铝粉煤灰中稀土元素  

Recovery of Rare Earth Elements from High Alumina Fly Ash by Alkali-Solution Desilication Combined with Mechanochemical Extraction Method

作　　者：张东晖 邢明飞[2] 吴小芳 董丽丽 张帆 ZHANG Donghui;XING Mingfei;WU Xiaofang;DONG Lili;ZHANG Fan(Jiaozuo Ecological Environment Monitoring Centre,Henan Province,Jiaozuo 454000,Henan,China;School of Resources and Envi ronment,Henan Polytechnic University,Jiaozuo 454000,Henan,China)

机构地区：[1]河南省焦作生态环境监测中心,河南焦作454000 [2]河南理工大学资源环境学院,河南焦作454000

出　　处：《有色金属(冶炼部分)》2025年第2期161-169,共9页Nonferrous Metals(Extractive Metallurgy)

基　　金：国家自然科学基金面上项目(52370135);河南省科技攻关项目(242102320079);河南理工大学杰出青年基金资助项目(J2022-2)。

摘　　要：采用碱溶脱硅联用机械化学提取法回收高铝粉煤灰(HAFA)中稀土元素(REEs),并同步获得高附加值富铝残渣。研究结果表明,HAFA中REEs主要富集在玻璃相中。碱溶脱硅工艺可以在温和条件下高效选择性溶解HAFA中玻璃相(保留富含铝的莫来石-刚玉相),并将REEs释放到NaOH溶液中转变成稀土氢氧化物沉淀。之后采用EDTA作为浸提剂,通过机械化学提取法高效、快速提取脱硅残渣中的REEs。在最佳浸提工艺条件下,La、Ce、Pr和Nd的提取效率分别为85.99%、83.30%、82.03%和88.71%,同时获得富铝渣(Al2O3质量分数为68.23%;Al/Si=2.52)。研究结果为HAFA绿色、高附加值回收利用提供新的思路。Alkali-solution desilication combined with mechanochemical extraction method was applied to recover rare earth elements(REEs)from high alumina fly ash(HAFA),and high value-added aluminium-rich residue was obtained simultaneously.The results show that REEs in HAFA are mainly enriched in the glass phase.The alkalisolution desilication process can be used to efficiently and selectively dissolve the glass phase(retain the aluminiumrich mullite-corundum phase)in HAFA under mild conditions,and release the REEs into NaOH solution to be converted into rare earth hydroxide precipitates.Then,EDTA was used as leaching agent to efficiently and rapidly extract the REEs from the desilication residue by mechanochemical method.Under the optimal conditions of the leaching process,the extraction efficiencies of La,Ce,Pr and Nd are 85.99%,83.30%,82.03%and 88.71%,respectively,while aluminium-rich slag is obtained(mass fraction of Al2O3 is 68.23%,and Al/Si=2.517).This study can provide a new strategy for the green and high value-added recycling of HAFA.

关 键 词：高铝粉煤灰 碱预脱硅 稀土元素回收 机械化学提取 EDTA 

分 类 号：TF845[冶金工程—有色金属冶金] TF821