还原酸浸对废旧稀土荧光粉中稀土提取的影响

Effect of reducing acid leaching on extracting rare earth from waste rare earth phosphor method

摘要: 为解决废旧稀土荧光粉中高价态Ce、Tb氧化物浸出困难的难题, 在碱熔焙烧预处理的研究基础上, 采用还原酸浸的方法, 以抗坏血酸作为还原剂, 来提高废旧稀土荧光粉的稀土浸出率。实验表明:在HCl浓度为4 mol/L, HCl与水洗渣液固比(单位为:mL/g, 下同)为10:1、抗坏血酸用量为10%、温度为338 K、时间为120 min、搅拌转速为650 r/min的条件下, 稀土浸出率可以达到98%以上。

Abstract: In order to solve the difficult problem of leaching of high-valence Ce and Tb oxides in waste rare earth phosphors, based on the research of alkali melting roasting pretreatment, this study adopted the method of reducing acid leaching and using ascorbic acid as a reducing agent to improve leaching rate of waste rare earth phosphor. The experiment showed that the experimental conditions such as hydrochloric acid concentration 4 mol/L, hydrochloric acid to water washing residue liquid solid ratio 10:1 mL/g, ascorbic acid dosage 10 wt%, leaching temperature 338 K, leaching time 120 min, stirring speed 650 r/min, the rare earth leaching rate could reach more than 98%.