钙热还原钇渣回收制备铝-钇中间合金的研究  

Preparation of Aluminum-Yttrium Master Alloy from Yttrium Smelting Slag

作　　者：陈燕飞[1] 朱政强[1] 徐玉友 吴世勇 赖华生 Chen Yanfei;Zhu Zhengqiang;Xu Yuyou;Wu Shiyong;Lai Huashen(Advanced Manufacturing School,Nanchang University,Nanchang 341000,China;Ganzhou Nonferrous Metallurgy Research Institute Co.,Ltd.,Ganzhou 341412,China)

机构地区：[1]南昌大学先进制造学院,江西南昌341000 [2]赣州有色冶金研究所有限公司,江西赣州341412

出　　处：《中国稀土学报》2024年第2期304-314,I0004,共12页Journal of the Chinese Society of Rare Earths

基　　金：江西省重点研发计划项目(20203BBG73070);江西省自然科学基金项目(20202BABA204009)资助。

摘　　要：钙热还原渣中一般残留一定量的稀土氟化物和稀土金属,具有较好的回收价值。但针对高丰度、廉价稀土钇渣的湿法回收工艺成本较高,所得产物价值较低,造成了钙热还原钇渣的回收难题。本工作通过设计精密的回收体系,采用火法回收钇渣中残留的稀土元素形成稀土金属,并在热还原过程中,促使还原得到的金属Y向金属Al中扩散,从而一步得到Al-Y中间合金。研究结果表明,钙热还原钇渣中残留的YF_(3)达12.51%(质量分数),且钇渣中夹杂了大量小尺寸的稀土金属。相应的回收实验发现,将熔炼温度设为1550℃,金属Ca的添加量为理论值的1.15倍时,钙热还原钇渣中Y元素的回收率达85%,所得到的Al-Y中间合金中形成了大量的Al_(3)Y_(5),Al_(43)Y_(6)W_(4)和Al_(4)Ca析出相。这些结果对于开发稀土冶炼渣的回收方法,促进稀土资源的高效利用具有一定的参考价值。A certain quantity of rare-earth fluorides and rare-earth metals are generally left in the corresponding yttrium smelting slag,making the yttrium smelting slag a good recovering value.However,the cost of wet recovery processes for high-abundance and cheap yttrium smelting slag is high but the value of the obtained product is low,which hinders the recovery of yttrium smelting slag.In this work,a sophisticated recovery system was designed,and the residual rare-earth elements in smelting slag were recovered and transformed into rare-earth metals.Moreover,the obtained rare-earth metals are promoted to diffuse into the molten aluminum during the thermal reduction process,thereby obtaining an aluminum-yttrium master alloy product in one step.The results indicate that the residual YF_(3)in yttrium smelting slag reaches 12.51%,and lots of small-sized yttrium metals are found to be included in the slag.The corresponding recovery experiments find that when the smelting temperature was set at 1550℃and the addition amount of metallic calcium is 1.15 times the theoretical value,the recovery rate of yttrium element from the smelting slag reaches 85%.The main precipitates in the obtained aluminum-yttrium master alloy are Al_(3)Y_(5),Al_(43)Y_(6)W_(4)andAl_(4)Ca.These results are of great significance for developing a new recovery method for rare-earth smelting slag and promoting the efficient utilization of rare earth resources.

关 键 词：稀土 钇 冶炼渣 中间合金 析出相 

分 类 号：TF845.3[冶金工程—有色金属冶金]