Upcycling Waste Polyethylene into Nylon Precursors and Platform Chemicals via A Hybrid Pyrolysis-Biomanufacturing Approach

通过混合热解-生物制造方法将废弃聚乙烯升级改造为尼龙前体和平台化学品

• 批准号: 2317307
• 负责人: Dongming Xie
• 金额: $ 46.31万
• 依托单位: University of Massachusetts Lowell
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2026-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2317307&HistoricalAwards=false
• 关键词: Upcycling; Waste; Polyethylene; into; Nylon

Polyethylene (PE) is one of the most commonly produced plastics, primarily used for plastic bags, containers, bottles, and toys. Currently, over 100 million tons of PE are produced annually, accounting for 34% of the total plastics market. Unfortunately, most PE products are single-use and discarded in landfills, and waste PE contributes to over 50% of the plastics waste stream. The projected 12% annual PE production rate growth combined with the lack of effective recycling options make PE a major environmental concern. To recycle or upcycle waste PE, mechanical disruption, thermochemical treatment, and biochemical conversion processes have been explored, but these methods all ultimately result in low product qualities, inefficient conversion rates to value-added products, and high processing costs. None of the existing PE recycling or upcycling methods alone will likely contribute to a circular plastics economy. The objective of this project is to explore a two-step hybrid oxidative catalytic pyrolysis–biochemical approach to upcycle waste PE into chemical products with significantly higher values. This concept takes advantage of the benefits of both thermochemical (oxidative catalytic pyrolysis) and biochemical (biomanufacturing) methods for plastics upcycling. The proposed technology will lead to reduced waste plastics disposal, mitigating its negative environmental impacts. As UML being one of the Minority Serving Institutions (MSI) in Massachusetts, the project team will recruit students from underrepresented groups from underserved communities of the state to conduct research. Outreach events targeting local high schools and learning-disabled students pursing STEM careers will also be planned via UML’s Biomanufacturing Center and Center for Autism Research and Education, respectively. A novel hybrid process is proposed to upcycle waste polyethylene (PE) into a series of value-added products. The first step of the proposed hybrid process consists of an oxidative pyrolysis reactor to decompose PE over redox metal oxide or mixed oxide catalysts on porous supports into C5–C20 alkanes, alcohols, aldehydes, and carboxylic acids. The fundamental chemical kinetics associated with reaction pathways on the catalyst surfaces, as well as the effects of species diffusion in the pores, will be quantified. Oxidative pyrolysis will be followed by a biomanufacturing step using an engineered yeast Yarrowia lipolytica to produce value-added platform chemicals such as long-chain diacids (LCDAs) as nylon precursors and triacetic acid lactone (TAL) and phloroglucinol (PG) for a wide spectrum of industrial applications. The research team will identify metabolic pathways leading to high yields of various products and will use reaction engineering principles to overcome mass transfer limitations in bioreactors. The success of this project will pave the way to a new paradigm, enabling future manufacturing of a wide range of strategic platform chemicals, particularly the molecules derived from the omega-oxidation, beta-oxidation, and related metabolic pathways, leading to more energy efficient, economical, and robust valorization of not only waste PE but also other similar waste polyolefins, such as polypropylene (PP) and polystyrene (PS).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.

聚乙烯（PE）是最常见的塑料之一，主要用于塑料袋，容器，瓶子和玩具。目前，每年生产超过1亿吨PE，占塑料总市场的34％。不幸的是，大多数PE产品都是一次性的，并在垃圾填埋场中丢弃，废物PE占塑料废物流的50％以上。预计年度PE生产率增长12％，加上缺乏有效的回收选择，使PE成为主要的环境问题。为了回收或升级废物PE，已经探索了机械破坏，热化学处理和生化转化过程，但是这些方法最终都导致产品质量低，转化率低，转化率低于增值产品以及高处理成本。仅现有的PE回收或升级方法都不会有助于循环塑料经济。该项目的目的是探索两步杂交氧化物催化热解 - 生物化学方法，以将其升级为具有较高值的​​化学产品。这个概念利用了热化学（氧化催化热解）和生化（生物制造）方法的益处，用于塑料升级。拟议的技术将导致废物塑料处置减少，从而减轻其负面环境的影响。由于UML是马萨诸塞州的少数族裔服务机构（MSI）之一，该项目团队将招募来自该州服务不足社区的人数不足的团体的学生进行研究。还将分别通过UML的生物制造中心和自闭症研究中心和教育中心计划，针对当地高中和学习障碍的学生的外展活动。提出了一种新型的混合过程，以将浪费聚乙烯（PE）升级为一系列增值产品。提出的杂种过程的第一步是由氧化物热解反应器组成，将PE分解在氧化还原金属氧化物或混合氧化物催化剂上，以多孔载体载入C5 -C20烷烃，醇，醛，醛和羧酸。将量化与催化剂表面上的反应途径以及物种扩散在孔中的基本化学动力学。氧化热解会之后，使用工程酵母Yarrowia脂溶剂的生物制造步骤，以产生增值平台化学物质，例如长链二硫酸（LCDAS），作为尼龙前体和三乙酸乳酸内酯（TAL）和菲洛戈属醇（PG），以及用于广泛的工业应用。研究小组将确定代谢途径，导致各种产品的产量高，并将使用反应工程原理克服生物反应器中的传质限制。该项目的成功将为新的范式铺平道路，从而使未来的各种战略平台化学物质，尤其是源自欧米茄氧化，β-氧化和相关的代谢途径的分子，并导致更节能的能源效率，经济，经济性，以及其他类似的浪费多质量（例如多重质量），以及诸如多重质量的pepo）（以及诸如多重质量的pep pe），以及（PS）。该奖项反映了NSF的法定使命，并通过使用基金会的知识分子优点和更广泛的影响审查标准来评估，被认为是宝贵的支持。