Shenzhen Key Laboratory of Circular Economy, Shenzhen Graduate School, Peking University, Shenzhen 518055, China.
College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, China.
Waste Manag. 2017 Nov;69:393-399. doi: 10.1016/j.wasman.2017.08.018. Epub 2017 Aug 10.
The recovery of four dominant plastics from electronic waste (e-waste) using mixed solvent extraction was studied. The target plastics included polycarbonate (PC), polystyrene (PS), acrylonitrile butadiene styrene (ABS), and styrene acrylonitrile (SAN). The extraction procedure for multi-polymers at room temperature yielded PC, PS, ABS, and SAN in acceptable recovery rates (64%, 86%, 127%, and 143%, respectively, where recovery rate is defined as the mass ratio of the recovered plastic to the added standard polymer). Fourier transform infrared spectroscopy (FTIR) was used to verify the recovered plastics' purity using a similarity analysis. The similarities ranged from 0.98 to 0.99. Another similar process, which was denoted as an alternative method for plastic recovery, was examined as well. Nonetheless, the FTIR results showed degradation may occur over time. Additionally, the recovery cost estimation model of our method was established. The recovery cost estimation indicated that a certain range of proportion of plastics in e-waste, especially with a higher proportion of PC and PS, can achieve a lower cost than virgin polymer product. It also reduced 99.6%, 30.7% and 75.8% of energy consumptions and CO emissions during the recovery of PC, PS and ABS, and reduced the amount of plastic waste disposal via landfill or incineration and associated environmental impacts.
研究了从电子废物(电子垃圾)中使用混合溶剂萃取回收四种主要塑料的方法。目标塑料包括聚碳酸酯(PC)、聚苯乙烯(PS)、丙烯腈-丁二烯-苯乙烯(ABS)和苯乙烯-丙烯腈(SAN)。多聚合物在室温下的萃取程序可获得可接受的回收率的 PC、PS、ABS 和 SAN(分别为 64%、86%、127%和 143%,其中回收率定义为回收塑料与添加标准聚合物的质量比)。傅里叶变换红外光谱(FTIR)用于通过相似性分析验证回收塑料的纯度。相似度范围从 0.98 到 0.99。还研究了另一种类似的过程,称为塑料回收的替代方法。然而,FTIR 结果表明,随着时间的推移,可能会发生降解。此外,还建立了我们方法的回收成本估算模型。回收成本估算表明,电子废物中一定比例的塑料,特别是 PC 和 PS 的比例较高,可以实现比原始聚合物产品更低的成本。它还减少了 PC、PS 和 ABS 回收过程中 99.6%、30.7%和 75.8%的能源消耗和 CO 排放,并减少了通过填埋或焚烧处理的塑料废物量和相关的环境影响。