摘要
以废旧稀土荧光粉经酸浸、苛性钠焙烧、水洗除铝后的除铝渣为原料,采用二段酸浸并进行正交实验优化酸浸条件。结果表明,一段酸浸时,各因素对稀土浸出影响顺序为:液固比>盐酸浓度>浸出时间>浸出温度>H2O2添加量。在液固比6∶1、盐酸浓度6 mol/L、浸出时间60 min、浸出温度60℃、H2O2添加8%(体积分数)优化条件下,稀土总浸出率为95.48%,残酸浓度为2.18 mol/L,杂质Al含量高达134 mmol/L,Fe含量为1.78 mmol/L,Si含量达到3.89 mmol/L;二段酸浸在浸出温度60℃、浸出时间60 min下,通过添加新鲜除铝渣调节浸出液终点pH值为4,二段酸浸液杂质Al、Fe、Si含量降低到24.1 mmol/L、<0.09 mmol/L、3.89 mmol/L,满足后续萃取要求。
With waste rare earth phosphor as the raw material after aluminum removal by acid leaching,caustic soda sintering and water washing,two-stage acid leaching and orthogonal experiment were used to optimize acid leaching conditions.The results show that the influence order of each factor on rare earth leaching in the first stage is as follows:liquid-solid ratio>HCl concentration>leaching time>leaching temperature>H2O2 dosage.Under the optimal conditions of solid-liquid Ratio of 6∶1,HCl concentration of 6 mol/L,leaching time of 60 min,leaching temperature of 60℃,and H2O2 dosage of 8%(volume fraction),the total rare earth leaching rate reaches 95.48%and the residual acid concentration is 2.18 mol/L,the concentration of Al impurity is up to 134 mmol/L,and Fe and Si are 1.78 mmol/L and 3.89 mmol/L,respectively.In the second stage,when the leaching temperature and time are 60℃and 60 min,and the pH value of the leaching solution is adjusted to 4 by adding fresh dealuminated slag,the concentration of Al,Fe and Si impurities in leaching solution is reduced to 24.1 mmol/L,<0.09 mmol/L and 3.89 mmol/L,meeting the requirements of subsequent extraction.
作者
朱尚萍
钟立钦
曾颜亮
黎振源
廖春发
ZHU Shang-ping;ZHONG Li-qin;ZENG Yan-liang;LI Zhen-yuan;LIAO Chun-fa(School of Metallurgical and Chemical Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,China)
出处
《稀有金属与硬质合金》
CAS
CSCD
北大核心
2019年第6期10-14,19,共6页
Rare Metals and Cemented Carbides
基金
国家自然科学基金项目(51464012)
关键词
废旧稀土荧光粉
除铝渣
正交实验
稀土浸出
二段酸浸
waste rare earth phosphor
dealuminated slag
orthogonal experiment
rare earth leaching
two-stage acid leaching
