两步酸浸法提高铈和铽浸出率的工艺研究  

Process of Two-Step Acid Leaching to Increase Cerium and Terbium Leaching Rate

作　　者：何玲[1] 尹延纬 孙福海 孙卫民[1] 李文生[1] He Ling;Yin Yanwei;Sun Fuhai;Sun Weimin;Li Wensheng(School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学材料科学与工程学院

出　　处：《中国稀土学报》2019年第6期697-703,I0002,共8页Journal of the Chinese Society of Rare Earths

基　　金：甘肃省重点研发计划项目(17JR7GA014);沈阳材料科学国家研究中心-有色金属加工与再利用国家重点实验室联合基金项目(18LHPY006)资助

摘　　要：为了提高废弃荧光粉中Ce4+和Tb3+的浸出率,采用两步酸浸法。研究了助浸剂对蓝粉和绿粉的镁铝尖晶石结构的破坏作用,不同酸浸工艺参数对Ce和Tb浸出率的影响;对添加助浸剂后的酸浸反应动力学进行研究,并采用阿伦尼乌斯方程计算酸浸反应活化能。结果表明:不同助浸剂对尖晶石结构破坏作用不同,质量比为1∶0.8的柠檬酸钠作为助浸剂效果最优。酸浸工艺参数对Ce4+和Tb3+的浸出率具有重要的影响,最优工艺:HNO3的浓度为2 mol·L^-1,浸出温度60℃,浸出时间为2 h,反应转速300 r·min^-1。在最优工艺和质量比为1∶0.8的柠檬酸钠作为助浸剂的条件下,Ce4+和Tb3+浸出率分别达到了98.88%和97.12%。通过建立酸浸反应动力学模型和计算酸浸反应活化能,得到了加入助浸剂的浸出过程受扩散控制。Two-step acid leaching was used to improve Ce4+and Tb3+leaching rate in waste phosphors.The damage effect of helper leaching agents on the structure of magnesia-alumina spinel with blue powder and green powder was studied.The effects of different acid leaching parameters on Ce4+and Tb3+leaching rate,and the reaction kinetics of acid leaching with the aid of helper leaching agents were studied.The activation energy of acid leaching was calculated by Arrhenius equation.The results showed that sodium citrate with a mass ratio of 1∶0.8 had the best effect on the structure destruction of spinel.The process parameters of acid leaching have an important effect on the leaching rate of Ce4+and Tb3+.The optimal process was:the concentration of nitric acid 2 mol·L^-1,leaching temperature 60℃,leaching time 2 h and reaction speed 300 r·min^-1.Under the condition that the optimal process and quality ratio of 1∶0.8 sodium citrate were used as the helper leaching agents,the leaching rate of Ce and Tb reached 98.88%and 97.12%,respectively.Through the establishment of the kinetic model of acid leaching and the calculation of activation energy of acid leaching,the leaching process with the aid agent was controlled by diffusion.

关 键 词：两步酸浸 铝镁尖晶石结构 酸浸动力学 浸出率 稀土 

分 类 号：TF845[冶金工程—有色金属冶金]