Nowadays, a large quantity of Light Emitting Diodes (LEDs) have been produced and updated with the development of optoelectronic industry. At the same time, many waste LEDs are discarded. However, there are many metals and non-metals in waste LEDs, which may cause secondary pollution and waste of resources if disposed improperly. In this study, solvent method was used to dissociate the waste LED modules and recycle resources. Firstly, the components of the waste LED modules were analyzed. The main component of the transparent plastic part, usually used as packaging materials, is cured epoxy resin, and the main component of the white plastic part as the skeleton of LED modules is a mixture of polyphenylene oxide (PPO) and polystyrene (PS). Then, eight organic solvents, [EMIM⁺]BF₄⁻ ion liquid and sodium hydroxide (NaOH) inorganic reagent were tried to separate a 40 × 40 mm² waste LED module respectively. The results showed that only three organic solvents—dimethylformamide (DMF), dimethylacetamide (DMA), dimethyl-sulfoxide (DMSO) could dissociate the waste LED module very well. The used DMF solution was purified by rotary evaporation, and the regenerative DMF solution could be reused because its property has not changed. The solid residue obtained after rotary evaporating DMF was identified as polystyrene (PS). It was inferred that the waste LED module was dissociated through the DMF dissolving the PS of white plastic. In addition, the effect of DMF, DMA and DMSO dissociating the waste LED modules with the change of temperature was discussed. It was found that the choice of suitable solvent is a key for this method, and the heating temperature was also a very important factor. Finally, it was measured that the cured epoxy resin and the white plastic of the waste LED module accounted for about 31.4% (w/w) and 37.7% (w/w) respectively, which can be recycled. In short, the method not only separated completely the waste LED module and its each part was recycled easily, but the solvents can be reused. This study suggests a new route to recycle LEDs due to its environmentally friendly process, which may exert a significantly beneficial impact on our environment.

如今，随着光电工业的发展，已经生产并更新了大量的发光二极管（LED）。同时，许多废弃的LED被丢弃。但是，废弃LED中有许多金属和非金属，如果处理不当，可能会造成二次污染和资源浪费。在这项研究中，使用溶剂法将废LED模块和回收资源分离。首先，分析了废弃LED模块的组成。通常用作包装材料的透明塑料部件的主要成分是固化环氧树脂，而作为LED模块骨架的白色塑料部件的主要成分是聚苯醚（PPO）和聚苯乙烯（PS）的混合物。然后，八种有机溶剂，[EMIM ⁺ ] BF ₄ ^-尝试使用离子液体和氢氧化钠（NaOH）无机试剂分离40×40 mm ²分别废弃LED模块。结果表明，只有三种有机溶剂，即二甲基甲酰胺（DMF），二甲基乙酰胺（DMA），二甲基亚砜（DMSO）才能很好地分解废LED模块。用过的DMF溶液通过旋转蒸发纯化，并且再生的DMF溶液由于其性质没有改变，因此可以重复使用。旋转蒸发DMF后获得的固体残留物被鉴定为聚苯乙烯（PS）。可以推断，废LED模块是通过DMF将白色塑料的PS溶解而分解的。此外，还讨论了DMF，DMA和DMSO随温度的变化使废LED模块分离的效果。已经发现选择合适的溶剂是该方法的关键，并且加热温度也是非常重要的因素。最后，据测量，废弃LED模块的固化环氧树脂和白色塑料分别约占31.4％（w / w）和37.7％（w / w），可以回收利用。简而言之，该方法不仅可以将废物LED模块完全分离，而且其各个部分都易于回收利用，而且溶剂可以重复使用。这项研究提出了一种回收LED的新途径，因为其环保工艺，这可能会对我们的环境产生显着的有益影响。