废弃LCD面板金属铟的超声协同浸出

随着LCD报废数量的逐年增多,废弃LCD面板所含金属铟的回收再用已成为铟资源回收领域急需解决的问题。为提高废弃LCD面板金属铟的回收效率,研究提出利用超声对其进行协同浸出,以硫酸为浸出液考察超声及不同反应条件对铟浸出效率的影响。研究结果显示,超声协同能有效提高铟的浸出效率,在实验参数范围内铟的浸出率随超声功率、反应温度及酸浓度的增加而增大,随物料粒径增大而减小。在超声功率为800 W、反应温度60~70℃、硫酸浓度0.5 mol/L、物料粒径小于0.5 mm条件下,浸出反应5 h铟的浸出率可达74.1%。在此基础上,研究进一步分析了超声对铟浸出反应的协同作用机制,指出热学与机械作用是超声促进废弃LCD面板金属铟浸出反应进行、提高铟浸出效率的主要作用机制。

Indium leaching from waste liquid crystal display(LCD) panels assisted with ultrasound

With the increase of waste LCDs,indium recovery from waste LCD panels has aroused wide attention.In order to improve the indium recovery efficiency from waste LCDs,ultrasound was proposed to leach indium from waste LCDs in this study.With sulfuric acid as the leaching medium,influence of ultrasound and different factors on the indium leaching rate was investigated.Results show that the ultrasonic assistance can effectively improve indium leaching rate,and the leaching rate increases with the increase of ultrasonic power,reaction temperature and acid concentration,decreases with the particle size increasing.Under the optimized conditions i.e.,ultrasound power of 800 W,reaction temperature of 60-70℃,sulfuric acid concentration of 0.5 mol/L,particle size smaller than 0.5 mm,74.1% of indium was leached into the acid.Based on the results,reaction mechanism of ultrasonic assistance was further analyzed.According to the analysis,thermal and mechanical effect produced by sonochemical is the main reaction mechanism for the indium leaching reaction,which significantly improves the indium leaching rate.