EFRI E3P: Valorization of Plastic Waste via Advanced Separation and Processing

该项目旨在通过关注两个具有挑战性的问题来减少最终进入垃圾填埋场或焚烧炉的废塑料数量和新产品所需的原始塑料数量：(1)混合塑料废物的分类和(2)回收塑料的计价。高通量的自动分拣将通过将记录每一块塑料的分子签名的新型传感器技术与机器学习相结合来完成，机器学习将根据该分子签名实时识别每一块塑料的特定类型。通过将这些新能力与现有技术相结合，出现了一种先进的混合废塑料分类工艺，该工艺适用于对其他材料进行分类，以实现其回收利用。分类塑料的回收将通过将选定类型的塑料溶解在环境友好的溶剂中来实现，以便回收所需类型的塑料(即聚烯烃)，将其从添加剂或杂质中分离出来，并使其适合于在新产品中重复使用。对聚烯烃进行量身定做的化学修饰将产生功能蜡，可用作高价值材料的构建块。这项研究有助于国家的先进制造能力，并有助于满足消费者的需求和公司承诺在其产品中加入高比例的回收塑料。组织了广泛的重点活动，以促进不同的学生群体参与研究任务，并与当地社区分享所产生的知识。这一基础工程研究项目的目标是使回收的废塑料比例和回收用于新产品的塑料的价值显著增加。为实现这一目标将实现两个目标：(目标1)：高通量多模式传感器识别和塑料废物的自主分类；(目标2)回收聚烯烃的物理和化学分子价态。目标1专注于开发新型光学传感器和先进的机器学习，用于不同类型塑料的实时、高通量分子水平检测。探测能力将与基于视觉的识别和跟踪相结合。将新开发的能力与现有技术相结合，将产生一种先进的分类工艺，可在现有的材料回收设施中部署，适应不同的塑料垃圾成分，可规模化，可升级，并可转移到其他行业。AIM 2将为塑料的更新开发物理和化学方法。环境友好的溶剂将用于通过溶解/沉淀处理含有其他聚合物、添加剂、填充物和/或杂质的聚烯烃塑料来回收原始聚合物。以聚烯烃为原料，开发了遥控短链聚乙烯蜡，可用作长链脂肪族聚酯、交联型聚烯烃等高价值材料的构建块，以及用于添加剂制造技术的树脂。该项目产生的基础和应用知识将对解决显著提高全球塑料回收率这一重大挑战产生变革性的影响。这一重大挑战在这里以对环境负责、技术可行、具有经济竞争力和社会利益的方式解决。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project aims to reduce both the amount of waste plastic that ends up in landfills or incinerators and the amount of virgin plastic required for new products by focusing on two challenging issues: (1) sorting of mixed plastic waste and (2) valorization of recovered plastic. High-throughput, automated sorting will be accomplished through the combination of novel sensor technology that will register the molecular signature of each piece of plastic, and machine learning that, on the basis of this molecular signature, will identify in real time the specific type of each piece of plastic. From the integration of these new capabilities with existing technologies, an advanced mixed waste plastic sorting process emerges that is adaptable to sorting other materials to enable their recycling as well. Upcycling of sorted plastic will be achieved through dissolution of select types of plastic in environmentally responsible solvents in order to recover the desirable type of plastic (i.e., polyolefins), separate it from additives or impurities, and render it suitable for reuse in new products. Tailored chemical modification of polyolefins will produce functional waxes that can serve as building blocks for high-value materials. This research contributes to the Nation's advanced manufacturing capabilities and helps meet both consumer demand for and corporate commitments to incorporating a high fraction of recycled plastic into their products. A broad range of focused activities are organized to facilitate the participation of a diverse student cohort in the research tasks and the sharing of the knowledge generated with the local community.The objective of this fundamental engineering research project is to enable a significant increase in both the fraction of waste plastic that is being recycled and in the value of plastic recovered for use in new products. Two aims will be pursued toward this objective: (Aim 1): high-throughput multi-modal sensor recognition and autonomous sorting of plastic waste and (Aim 2) physical and chemical molecular valorization of recovered polyolefins. Aim 1 focuses on developing novel optical sensors and advanced machine learning for the real-time, high-throughput molecular-level detection of different types of plastics. The detection capabilities will be coupled with vision-based recognition and tracking. The integration of the newly developed capabilities with existing technologies will result in an advanced sorting process that is deployable in existing materials recovery facilities, adaptable to variable plastic waste composition, scale-able, upgradable, and transferable to other industries. Aim 2 will develop physical and chemical methodologies for the upcycling of plastics. Environmentally responsible solvents will be used for the recovery of pristine polymers via dissolution/precipitation processing of polyolefin-based plastics that incorporate other polymers, additives, fillers, and/or impurities. From a polyolefin starting material, telechelic short-chain polyethylene waxes are developed, which can be used as building blocks for high-value materials such as long-chain aliphatic polyester, cross-linked polyolefins, and resins for additive manufacturing technologies. The fundamental and applied knowledge generated in this project is poised to have a transformative impact on addressing the grand challenge of significantly increasing the global plastic recycling rates. This grand challenge is tackled here in a manner that is environmentally responsible, technically feasible, economically competitive, and societally beneficial.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.