通过热解和浸出工艺从废旧发光二极管(LEDs)中回收有价金属.通过对热解后的LED预先筛分可回收98.16%Ga和99.54%Y.采用单因素试验和响应曲面法研究不同浸出条件对铁、铜和银浸出的影响.利用无氧化剂H2SO4浸出法从废旧LED中选择性回收约90.15%Fe,Fe浸出渣通过添加HNO3浸出可以回收99.55%Cu和99.36%Ag.XRD和SEM?EDS分析证实,所开发的工艺可以高效地从废旧LED中浸出Fe和Cu.
The valuable metals were separated and extracted from waste light-emitting diodes (LEDs) by pyrolysis and leaching process. About 98.16%Ga and 99.54%Y were recycled from the LEDs after the pyrolysis by sieving process in advance. The effects of various leaching conditions on the extraction of Fe, Cu and Ag were investigated by single factor experiments and response surface method. About 90.15%Fe was selectively extracted from the waste LEDs by H2SO4 leaching without oxidant, and 99.55%Cu and 99.36%Ag were recovered from the iron leaching residue by acid leaching with the addition of HNO3. The XRD and SEM?EDS analyses confirmed that the iron and copper were effectively extracted from the waste LEDs by the developed process.