Catalytic Upgrading of Polymer Waste into Value-Added Products

塑料在现代社会的发展中发挥了工具作用，但与该行业相关的日益增长的环境问题引发了对可再生替代品的需求。事实上，很明显，随着行业从线性经济向循环经济转变，有必要制定替代废物管理战略，以补充生物基和可生物降解塑料的引入。因此，该项目的目的是：-研究商业生物基塑料（例如PLA）的催化升级（通过化学回收），使其成为增值产品，例如乳酸酯或丙烯酸，这些产品被认为是传统石油化学溶剂/化学品的潜在绿色替代品。该工艺的关键方面包括：开发新型的工业上可行的催化剂（即使用廉价/丰富的金属和可扩展的配体系统）。温和条件下的高选择性和产率，金属介导的降解实例仍然有限。事实上，目前的回收方法依赖于苛刻的反应条件，是资源/能源密集型的，在机械回收的情况下会导致最终的材料“降级循环”。- 在新型旋转圆盘反应器上展示工艺可扩展性，通过在化学和工程之间的边界工作，采用跨学科的研究方法。将已建立的方法扩展到其他商业相关的聚酯，包括PET和PEF，以及其他聚合物类别：聚碳酸酯，聚酰胺等。将开发的催化剂固定在载体上，以克服与催化剂回收相关的工业问题，这是均相催化剂的一个限制性特征。这也将有助于提升现有的回收技术。此外，还将研究制备的所有新型催化剂在溶液中和在用于PLA生产和用于聚碳酸酯形成（CO2/环氧化物或酸酐/环氧化物）的工业优选熔融条件下在rac-LA的ROP中的活性。感兴趣的聚合物将使用标准的热/机械表征技术进行表征。项目策略：1.制备可缩放配体，例如席夫碱。与多种地球上丰富的金属络合，例如第（I）族、第（II）族和Zn。3.催化测试（批量和流动）。4.通过实验和计算建模，评估催化数据，确定结构-活性关系，了解催化升级过程.开发催化反应器，以扩大降解规模，并从废料中制备增值产品。参考文献：1. J. Payne，P. McKeown和M. D.琼斯波利姆德格勒。刺杀，2019，165，170-181.

Plastics have played an instrument role in the development of modern day society, but growing environmental concerns associated with the industry has created an appetite for renewable alternatives. Indeed, it is clear the development of alternative waste management strategies is necessary to compliment the introduction of bio-based and biodegradable plastics as the industry shifts from a linear to circular economy. Thus, this project aims to:- Investigate catalytic upgrading (via chemical recycling) of commercially bio-based plastics (e.g. PLA) into value-added products, such as lactate esters or acrylic acid, which have been cited as potential green substitutes for traditional petrochemical based solvents/chemicals. Key aspects to this process include:Development of novel, industrially viable catalysts (i.e. using cheap/abundant metals and scalable ligands systems).- High selectivity and yield under mild conditions, with metal-mediated degradation examples remaining limited. Indeed, current recycling methods rely on harsh reaction conditions, are resource/energy intensive and lead to eventual material 'downcycling' in the case of mechanical recycling 1 Chemical recycling has the potential to address these concerns. - Demonstrate process scalability on a novel spinning disc reactor, adopting an interdisciplinary approach to research by working at the boundary between chemistry and engineering.- Extend established methodologies to other commercially relevant polyesters, including PET and PEF, but also other polymer classes: polycarbonates, polyamides etc.- Immobilize developed catalysts on a support to overcome industry concerns associated with catalyst recovery, a limiting feature of homogeneous catalysts. This will also assist in upscaling the established recycling technology. Additionally, all novel catalysts prepared will also be investigated for their activity in the ROP of rac-LA in both solution and under industrially preferred melt conditions for PLA production and for polycarbonate formation (CO2/epoxide or anhydride/epoxide). Polymer of interest will be characterised using standard thermal/mechanical characterisation techniques.Project strategy:1. Preparation of scalable ligands, for example Schiff-Base.2. Complexation to broad range of earth abundant metals e.g. Group (I), Group (II) and Zn.3. Catalytic testing (batch and in flow).4. Evaluate catalytic data to determine structural-activity relationships to understand catalytic upgrading processes through experimental and computational modelling.5. Develop catalytic reactor to scale up the degradation and to prepare value-added products from waste materials. References:1. J. Payne, P. McKeown and M. D. Jones, Polym. Degrad. Stab., 2019, 165, 170-181.