Charitopoulou Maria-Anna, Vouvoudi Evangelia C, Achilias Dimitris S
Laboratory of Polymers and Colours Chemistry and Technology, Department of Chemistry, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Macedonia, Greece.
Polymers (Basel). 2024 Aug 14;16(16):2299. doi: 10.3390/polym16162299.
Thermochemical recycling of plastics in the presence of catalysts is often employed to facilitate the degradation of polymers. The choice of the catalyst is polymer-oriented, while its selection becomes more difficult in the case of polymeric blends. The present investigation studies the catalytic pyrolysis of polymers abundant in waste electric and electronic equipment (WEEE), including poly(acrylonitrile-butadiene-styrene) (ABS), high-impact polystyrene (HIPS) and poly(bisphenol-A carbonate) (PC), along with their blends with polypropylene (PP) and poly(vinyl chloride) (PVC). The aim is to study the kinetic mechanism and estimate the catalysts' effect on the activation energy of the degradation. The chosen catalysts were FeO for ABS, Al-MCM-41 for HIPS, AlO for PC, CaO for Blend A (comprising ABS, HIPS, PC and PP) and silicalite for Blend B (comprising ABS, HIPS, PC, PP and PVC). Thermogravimetric experiments were performed in a N atmosphere at several heating rates. Information on the degradation mechanism (degradation steps, initial and final degradation temperature, etc.) was attained. It was found that for pure (co)polymers, the catalytic degradation occurred in one-step, whereas in the case of the blends, two steps were required. For the estimation of the activation energy of those degradations, isoconversional kinetic models (integral and differential) were employed. In all cases, the catalysts used were efficient in reducing the estimated , compared to the values of obtained from conventional pyrolysis.
在催化剂存在的情况下对塑料进行热化学回收通常用于促进聚合物的降解。催化剂的选择以聚合物为导向，而在聚合物共混物的情况下其选择变得更加困难。本研究考察了废弃电子电气设备（WEEE）中含量丰富的聚合物的催化热解，包括聚（丙烯腈-丁二烯-苯乙烯）（ABS）、高抗冲聚苯乙烯（HIPS）和聚（双酚A碳酸酯）（PC），以及它们与聚丙烯（PP）和聚氯乙烯（PVC）的共混物。目的是研究动力学机理并评估催化剂对降解活化能的影响。所选用的催化剂分别为用于ABS的FeO、用于HIPS的Al-MCM-41、用于PC的AlO、用于共混物A（包含ABS、HIPS、PC和PP）的CaO以及用于共混物B（包含ABS、HIPS、PC、PP和PVC）的硅沸石。在氮气气氛中以几种升温速率进行了热重实验。获得了关于降解机理（降解步骤、初始和最终降解温度等）的信息。结果发现，对于纯（共）聚合物，催化降解为一步进行，而对于共混物，则需要两步。为了估算这些降解的活化能，采用了等转化率动力学模型（积分和微分）。在所有情况下，与传统热解得到的值相比，所使用的催化剂在降低估算的[此处原文缺失相关内容]方面是有效的。
