Department of Materials and Manufacturing Technology, Chalmers University of Technology, 41296 Göteborg, Sweden.
Waste Manag. 2013 Apr;33(4):915-22. doi: 10.1016/j.wasman.2012.12.022. Epub 2013 Jan 27.
The compositions of three WEEE plastic batches of different origin were investigated using infrared spectroscopy, and the metal content was determined with inductively coupled plasma. The composition analysis of the plastics was based mainly on 14 samples collected from a real waste stream, and showed that the major constituents were high impact polystyrene (42 wt%), acrylonitrile-butadiene-styrene copolymer (38 wt%) and polypropylene (10 wt%). Their respective standard deviations were 21.4%, 16.5% and 60.7%, indicating a considerable variation even within a single batch. The level of metal particle contamination was found to be low in all samples, whereas wood contamination and rubber contamination were found to be about 1 wt% each in most samples. In the metal content analysis, iron was detected at levels up to 700 ppm in the recyclable waste plastics fraction, which is of concern due to its potential to catalyse redox reactions during melt processing and thus accelerate the degradation of plastics during recycling. Toxic metals were found only at very low concentrations, with the exception of lead and cadmium which could be detected at 200 ppm and 70 ppm levels, respectively, but these values are below the current threshold limits of 1000 ppm and 100 ppm set by the Restriction of Hazardous Substances directive.
研究了来自不同来源的三个 WEEE 塑料批次的组成，使用红外光谱法确定了金属含量。塑料的组成分析主要基于从实际废物流中收集的 14 个样本，结果表明主要成分是高抗冲聚苯乙烯（42wt%）、丙烯腈-丁二烯-苯乙烯共聚物（38wt%）和聚丙烯（10wt%）。它们各自的标准偏差分别为 21.4%、16.5%和 60.7%，即使在单个批次内也存在相当大的变化。所有样品中的金属颗粒污染水平都较低，而在大多数样品中，木材污染和橡胶污染分别约为 1wt%。在金属含量分析中，在可回收废塑料部分中检测到铁的含量高达 700ppm，由于其在熔融加工过程中可能催化氧化还原反应，从而加速塑料在回收过程中的降解，因此这是令人关注的。除了铅和镉，仅在非常低的浓度下发现有毒金属，铅和镉的含量分别为 200ppm 和 70ppm，但这些值低于有害物质限制指令设定的当前阈值 1000ppm 和 100ppm。
