Fiorente Annarita, D'Agostino Germano, Petrella Andrea, Todaro Francesco, Notarnicola Michele
Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via E. Orabona n. 4, 70125 Bari, Italy.
Materials (Basel). 2024 Jun 20;17(12):3041. doi: 10.3390/ma17123041.
Increasing demand for electrical and electronic equipment results in the generation of a rapidly growing waste stream, known by the acronym WEEE (waste electrical and electronic equipment). The purpose of this study was to evaluate the effectiveness of green sink-float treatment in sorting plastic polymers typically found in WEEE (PP, ABS, PA6, PS, and PVC). Molasses, a by-product of sugar bio-refining, was added in various concentrations to water to form solutions at different densities. The methodology was initially tested on virgin polymers; later, it was applied to plastics from a WEEE treatment plant. The polymers were characterised through near infrared spectroscopy (NIRS) and Fourier-transform infrared spectroscopy (FTIRS) analyses; the detection of any additives and flame retardants was conducted using the sliding spark technology (SSS2) and scanning electron microscope (SEM-EDX). The results showed that, for plastics from WEEE, the recovery efficiency was 55.85% for PP in a solution of tap water while the remaining part of PP (44.15%) was recovered in a solution of water to which 90% molasses was added. Furthermore, 100% recovery efficiency was obtained for PS and 93.73% for ABS in a solution of tap water with the addition of 10% / molasses. A recovery efficiency of 100% was obtained for PVC and 100% for PA6 in a solution consisting solely of molasses.
对电气和电子设备需求的不断增加导致产生了快速增长的废物流，其简称为WEEE（废弃电气和电子设备）。本研究的目的是评估绿色沉浮处理在分选WEEE中常见的塑料聚合物（PP、ABS、PA6、PS和PVC）方面的有效性。糖生物精炼的副产品糖蜜以不同浓度添加到水中，以形成不同密度的溶液。该方法最初在原始聚合物上进行测试；后来，将其应用于来自WEEE处理厂的塑料。通过近红外光谱（NIRS）和傅里叶变换红外光谱（FTIRS）分析对聚合物进行表征；使用滑动火花技术（SSS2）和扫描电子显微镜（SEM-EDX）检测任何添加剂和阻燃剂。结果表明，对于来自WEEE的塑料，在自来水溶液中PP的回收效率为55.85%，而PP的其余部分（44.15%）在添加了90%糖蜜的水溶液中回收。此外，在添加了10%糖蜜的自来水溶液中，PS的回收效率为100%，ABS的回收效率为93.73%。在仅由糖蜜组成的溶液中，PVC的回收效率为100%，PA6的回收效率为100%。
