Abstract: A comparison study for extraction of rare earths from waste Cathode Ray Tube (CRT) phosphors was carried out before and after dilute acid pretreatment process. The results show that the optimum conditions for the pretreatment process are as follows: hydrochloric acid concentration 0.8 mol·L^-1, reaction temperature 65℃, and leaching time 2 h. Compared with the untreated sample, extraction rate of rare earths for pretreated sample increases from 21.18% to 60.17%, whereas for impurities the rate decreases from 45.21% to 10.43%. The rare earth products obtained after precipitation and sintering are mainly Y₂O₃ and Eu₂O₃, total content of rare earth oxides 98.20% among them Y₂O₃ 90.25%, which are of cubic crystal, and close integration of lamella crystals to form a compact structure. The dilute acid pretreatment process can not only improve the efficiency of rare earth extraction and achieve sustainable and efficient utilization of rare earth resources, but also reduce the consumption of reagent and provide research foundation and technical support for comprehensive utilization of waste electronic products.

Key words: waste CRT phosphors, pretreatment, rare earth, leaching, optimization, recovery

摘要： 采用稀盐酸预处理工艺，对预处理前后废弃CRT荧光粉中稀土的提取效果进行了比较研究。结果表明，预处理工艺的最佳条件为：盐酸浓度为0.8 mol·L^-1，反应温度为65℃，反应时间为2 h。与未预处理样品相比，预处理样品酸解后得到的浸出液中稀土的浸出率由21.18%提高到60.17%，而杂质的浸出率由45.21%减少到10.43%。经沉淀、煅烧后所得稀土产物为Y₂O₃和Eu₂O₃，总含量为98.20%。其中，Y₂O₃含量为90.25%。稀土产物主要为立方晶型的Y₂O₃，由片状晶体密集堆积而成，片晶之间紧密结合，形成密实的方体结构。稀酸预处理工艺不仅能显著提高废弃CRT荧光粉中稀土提取的效率，实现稀土资源的高效、可持续利用，而且可以减少化学试剂的消耗，为废弃电子产品的综合利用提供研究基础与技术支撑。

关键词: 废弃CRT荧光粉, 预处理, 稀土, 浸取, 优化, 回收