Chemical recycling of solid plastic waste (SPW) is a paramount opportunity to reduce marine and land pollution and to enable the incorporation of the circular economy principle in today's society. In addition to more conscious behaviors and wiser product design (“design for recycling”), a key challenge is the identification of the leading recycling technologies, minimizing the global warming potential in an industrially relevant context. Chemical recycling technologies based on pyrolysis and gasification are leading the way because of their robustness and good economics, but an improved understanding of the chemistry and more innovative reactor designs are required to realize a potential reduction of greenhouse gas emissions of more than 100 million tonnes of CO₂-eq., primarily by more efficient use of valuable natural resources. The feed flexibility of thermal processes supports the potential of pyrolysis and gasification, however, the strong variability in time and space of blending partners such as multiple and co-polymers, additives, and contaminants (such as inorganic materials) calls for accurate assessment through fundamental experiments and models. Such complex and variable mixtures are strongly sensitive to the process design and conditions: temperature, residence time, heating rates – severity, mixing level, heat and mass transfer strongly affect the thermal degradation of SPW and its selectivity to valuable products. A prerequisite in improving design and performance is the ability to model conversion profiles and product distributions based on accurate rate coefficients for the dominating reaction families established using first-principle derived transport and thermodynamic properties. These models should also help with the “design for recycling” strategy to increase recyclability, for example by identifying additives that make chemical recycling difficult. Fundamental experiments of increased quality (accuracy, integrity, validity, replicability, completeness) together with improved deterministic kinetic models, systematically developed according to the reaction classes and rate rules approach, provide insights to identify optimal process conditions. This will allow shedding some light upon the important pathways involved in the thermal degradation of the feedstock and the formation/disappearance of desired or unwanted products. In parallel, the intrinsic kinetics of the dominating elementary reaction steps should be determined with higher accuracy, moving beyond single step kinetics retrieved from thermogravimetric analysis experiments. Together with more accurate kinetic parameters, better models to account for heat and mass transfer limitations also need to be further developed, since plastic degradation involves at least three phases (solid, liquid, gas), whose interactions should be accounted for in a more rigorous way. Novel experimental approaches (e.g. detailed feedstock and product characterization using comprehensive chromatographic techniques and photoionization mass spectrometry) and available computational tools (e.g. kinetic Monte Carlo, liquid phase, and heterogeneous theoretical kinetics) are needed to tackle these problems and improve our fundamental understanding of chemical recycling of SPW.

固体塑料废物（SPW）的化学回收是减少海洋和土地污染并使循环经济原则融入当今社会的最重要机会。除了更自觉的行为和更明智的产品设计（“可循环利用的设计”）之外，关键的挑战是确定领先的可循环利用技术，从而在与工业相关的情况下最大程度地降低全球变暖的可能性。基于热解和气化的化学循环技术因其坚固性和良好的经济性而处于领先地位，但是需要对化学有更深入的了解并需要更多创新的反应器设计，才能实现减少超过1亿吨温室气体排放的潜力。一氧化碳₂-eq。，主要是通过更有效地利用宝贵的自然资源。热过程的进料灵活性支持热解和气化的潜力，但是，诸如多种和共聚体，添加剂和污染物（例如无机材料）等共混物的时间和空间的强烈可变性要求通过基本方法进行准确评估实验和模型。这种复杂多样的混合物对工艺设计和条件非常敏感：温度，停留时间，加热速率–强度，混合程度，热量和传质强烈影响SPW的热降解及其对有价值产品的选择性。改进设计和性能的先决条件是能够基于使用第一原理导出的传输和热力学性质建立的主要反应族的准确速率系数，对转化曲线和产物分布进行建模的能力。这些模型还应有助于“回收设计”策略，以提高可回收性，例如通过识别使化学回收变得困难的添加剂。根据反应类别和速率规则方法系统开发的提高质量（准确性，完整性，有效性，可复制性，完整性）以及改进的确定性动力学模型的基础实验，可为识别最佳工艺条件提供见解。这将使人们对与原料热降解以及所需或不想要的产品的形成/消失有关的重要途径有所了解。同时，应以更高的精度确定主要的基本反应步骤的内在动力学，超越从热重分析实验中获得的单步动力学。结合更精确的动力学参数，还需要进一步开发更好的模型来解决传热和传质的局限性，因为塑性降解涉及至少三个阶段（固，液，气），其相互作用应更严格地加以考虑。道路。新颖的实验方法（应该以更高的精度确定主要的基本反应步骤的内在动力学，而不是从热重分析实验中获得的单步动力学。结合更精确的动力学参数，还需要进一步开发更好的模型来解决传热和传质的局限性，因为塑性降解涉及至少三个阶段（固，液，气），其相互作用应更严格地加以考虑。道路。新颖的实验方法（应该以更高的精度确定主要的基本反应步骤的内在动力学，而不是从热重分析实验中获得的单步动力学。结合更精确的动力学参数，还需要进一步开发更好的模型来解决传热和传质的局限性，因为塑性降解涉及至少三个阶段（固，液，气），其相互作用应更严格地加以考虑。道路。新颖的实验方法（由于塑料降解涉及至少三个阶段（固体，液体，气体），因此应更严格地考虑其相互作用。新颖的实验方法（由于塑料降解涉及至少三个阶段（固体，液体，气体），因此应更严格地考虑其相互作用。新颖的实验方法（例如，需要使用综合色谱技术和光电离质谱技术对原料和产品进行详细的表征，并需要可用的计算工具（例如动力学蒙特卡洛，液相和非均相理论动力学）来解决这些问题，并提高我们对SPW化学回收的基本认识。