Catalytic Microwave Process for Upgrading of Pyrolysis Liquids from Ubiquitous Plastic Wastes

塑料在现代生活中无处不在，全球年产量约为2.6亿吨，2019年仅有9%的塑料被回收利用。总共生产了83亿吨塑料，预计到2050年，垃圾填埋场或环境中的塑料将达到120亿吨，需要400年才能自然降解。未来，塑料的需求和生产预计将强劲增长，而对温室效应的担忧要求减少二氧化碳排放和对化石燃料的依赖，以满足立法要求。塑料可以通过一系列机械、热和化学技术进行回收，每种方法都有优缺点。一些化学回收技术，如糖酵解，只适用于特定类型的聚合物。其他方法，如机械回收，生产的产品等级较低，而热能技术需要很高的能量投入。混合废物，包括聚氯乙烯等卤化聚合物，是一个挑战，因为氯是一种潜在的催化剂毒物。因此，需要一种回收和升级工艺，可以处理一系列来自聚合物的不同热解油作为混合废流的一部分，可以处理污染物并产生增值产品。在CataWave中，我们的目标是解决上述问题，并开发一种强大且节能的工艺来升级从一系列塑料废流中提取的热解液。为此，我们将几项新的必要技术结合在一起，其中将包括开发定制的催化剂，以有效地提升热解油的质量。它们将由工业金属加工或采矿副产品(如赤泥)和已知的碳氢化合物裂解催化剂(如ZSM-5沸石)配制而成，选定的样品将包含对微波敏感的碳颗粒，以帮助其加热。我们将评估流动反应器中的微波或感应加热是否可以提供比传统电阻加热更有效和更节能的过程，并与所开发的催化剂相结合。升级后的石油产品将使用一系列技术进行表征，目的是升级以增加产品的价值，包括升级以满足临时燃料所需的标准。新鲜的和废弃的催化剂将使用一系列技术来表征，以了解它们的催化行为和失活。实验研究的结果将被应用于开发包含组分基团的集总方法的动力学模型，该模型将被用于为工业化过程的反应器的设计和放大提供信息。将开发技术经济模型，以告知流程的可伸缩性和盈利能力，例如选择吨位吞吐量、分散或集中处理废物。我们已经聘请了来自废物生产、回收、燃料和过程模拟领域的项目合作伙伴，包括Sabien Technology Plc、Halcle cle、Severn Trent Green Power、Pressvess和三菱化学。他们将提供用于升级的裂解油样品，就催化剂配方提供建议，协助工艺设计和经济评估，就工作计划提供技术咨询，并帮助建立他们的支持信中概述的商业化和影响交付的路线。

Plastics are ubiquitous in modern life, with global production of ~260 million tonnes per year and only 9 % recycled in 2019. 8.3 billion tonnes of plastic have been produced in total and predicted 12 billion tonnes in landfill or environment by 2050, taking 400 years to degrade naturally. In future, a strong growth in demand for and production of plastics is expected, whilst concerns for the greenhouse effect necessitate that carbon dioxide emissions and reliance on fossil fuels are decreased to meet legislation. Plastics can be recycled via a range of mechanical, thermal and chemical techniques, each route having advantages and disadvantages. Some chemical recycling techniques, such as glycolysis, are applicable only to particular types of polymer. Other routes, such as mechanical recycling, produce a lower grade product, whilst thermal techniques require a high energy input. Mixed waste, including halogenated polymers such as polyvinyl chloride presents a challenge, as the chlorine is a potential catalyst poison. A recycling and upgrading process is thus required that can process a range of different pyrolysis oils derived from polymers as part of a mixed waste stream, can deal with contaminants and produce a value-added product.In Catawave we aim to address the above issues and develop a robust and energy efficient process to upgrade pyrolysis liquids derived from a range of plastic waste streams. To do this we bring together several novel requisite technologies, which will include the development of bespoke catalysts to effectively upgrade the pyrolysis oils. These will be formulated from industrial metal processing or mining waste by-products such as 'red mud' and known hydrocarbon cracking catalysts such as zeolite ZSM-5, and select samples will incorporate microwave susceptible carbon particles to aid their heating. We will assess whether microwave or induction heating in a flow reactor can deliver a more effective and energy efficient process compared with conventional resistive heating, in conjunction with the developed catalysts. The upgraded oil products will be characterised using a range of techniques, with aim of upgrading to increase the value of products, including upscaling to meet standards required for drop-in fuels. Fresh and spent catalyst will be characterised using a range of techniques to understand their catalytic behaviour and deactivation. The results of the experimental studies will be applied to develop a kinetic model using lumped approach comprising component groups, which would be used to inform the design and scale-up of reactors for an industrialised process. Techno-economic modelling will be developed to inform the process scalability and profitability, for example the selection of tonnage throughput, distributed or centralised processing of waste. We have engaged Project Partners from across the waste producing, recycling, fuels and process simulation sectors including Sabien Technology Plc, Halocycle, Severn Trent Green Power, Pressvess and Mitsubishi Chemical. They will provide samples of pyrolysis oil for upgrading, advise on catalyst formulations, assist with process design and economic evaluation, give technical consultation on the work plan and help setup routes to commercialisation and impact delivery as outlined in their letters of support.