催化学报 ›› 2025, Vol. 71: 54-69.DOI: 10.1016/S1872-2067(24)60273-1

• 综述 • 上一篇    下一篇

塑料废弃物升级回收时代的分子筛催化剂: 迈向循环经济与可持续发展

刘青a, 尚进b, 刘振东a,*()   

  1. a清华大学化学工程系 化学工程与低碳技术全国重点实验室, 北京 100084
    b香港城市大学能源与环境学院, 香港
  • 收稿日期:2024-12-03 接受日期:2025-03-03 出版日期:2025-04-18 发布日期:2025-04-13
  • 通讯作者: * 电子信箱: liuzd@tsinghua.edu.cn (刘振东).
  • 基金资助:
    国家自然科学基金(22278237);国家自然科学基金(22478219)

Zeolites in the epoch of catalytic recycling plastic waste: Toward circular economy and sustainability

Qing Liua, Jin Shangb, Zhendong Liua,*()   

  1. aState Key Laboratory of Chemical Engineering and Low-Carbon Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China
    bSchool of Energy and Environment, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
  • Received:2024-12-03 Accepted:2025-03-03 Online:2025-04-18 Published:2025-04-13
  • Contact: * E-mail: liuzd@tsinghua.edu.cn (Z. Liu).
  • About author:Zhendong Liu (State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University) received his bachelor’s degree and master’s degree, both in Chemical Engineering, from Shandong University in 2005 and from Tsinghua University in 2012, respectively. He then moved to The University of Tokyo to pursue his doctoral degree and received a Ph.D. in Chemical Engineering in 2015. Thereafter, he worked as a postdoctoral researcher in UTokyo (with Prof. Tatsuya Okubo) and in University of Minnesota at Twin Cities (with Prof. Michael Tsapatsis and Prof. Andreas Stein). He joined Department of Chemical System Engineering at UTokyo as an assistant professor in 2017. Prof. Zhendong Liu moved to Tsinghua University and started his independent career in June 2021, and his research group currently focuses on innovating functional porous materials for catalysis and gas separation. He won a Dean’s Award in Research from UTokyo (2016) and was selected as an Emerging Investigator by Reaction Chemistry & Engineering (2024).
  • Supported by:
    National Natural Science Foundation of China(22278237);National Natural Science Foundation of China(22478219)

摘要:

塑料作为现代社会不可或缺的材料, 其全球年产量已超过4亿吨, 但目前仅有约9%实现了有效回收. 大量废弃塑料主要通过填埋或焚烧处理, 不仅造成严重的环境污染(如微塑料污染、温室气体排放), 还导致资源浪费. 传统机械回收因塑料种类复杂、性能退化等问题难以实现闭环循环. 在此背景下, 化学回收技术(如催化裂解、氢解)因其可将废塑料高效转化为高附加值化学品或燃料, 逐渐成为研究热点. 其中, 分子筛作为一类多孔固体酸催化剂, 凭借其可调控的酸性、高热稳定性、分子筛效应及工业成熟度, 在塑料催化转化过程中展现出独特优势. 然而, 相较于石油炼制和生物质转化等领域, 分子筛在塑料化学回收中的系统性研究仍处于起步阶段. 本文系统综述了分子筛基催化体系在塑料升级回收中的最新进展, 探讨其经济性与可持续性, 并展望未来研究方向.
本研究聚焦于分子筛基催化体系在塑料化学回收中的应用, 并通过多维度分析揭示其科学机理与工业化潜力. 首先, 探讨了分子筛的结构特性(如孔径分布、酸性调控和金属修饰)对催化性能的影响, 为塑料化学回收催化剂的定向调控提供理论支撑; 同时, 结合生命周期分析与技术经济评估的最新研究进展, 系统评估了分子筛催化技术在塑料化学回收过程中的环境与经济优势. 其次, 梳理了分子筛在聚烯烃及聚酯裂解中的反应机理及相关研究进展. 研究表明, 在聚烯烃催化裂解过程中, 反应主要遵循碳正离子链式机理, 其中末端断裂与随机断裂路径的竞争受到分子筛酸性和孔道尺寸的精准调控; 对于聚酯类塑料, 水解、醇解等途径可实现高效单体回收, 而双功能催化剂通过氢解-芳构化串联反应, 可实现高选择性转化, 由此展现出分子筛在复杂反应网络中的精准调控能力. 此外, 重点介绍了金属-分子筛双功能催化体系在塑料氢解及加氢裂解中的最新进展, 系统分析了金属组分、载体结构及酸性调控对催化性能的影响, 并深入探讨了该体系在温和条件下实现高效聚烯烃降解的巨大潜力及其面临的挑战.
本文系统阐述了分子筛催化技术在塑料废弃物升级回收时代所面临的重大机遇. 值得注意的是, 尽管分子筛催化剂在塑料化学回收领域展现出优异的催化活性和经济可行性, 其工业化应用仍面临诸多挑战. 未来研究应重点聚焦分子筛纳米结构的精准调控、金属-分子筛协同催化机制、混合塑料的高效分解以及与光电催化体系的耦合集成策略, 以推动塑料化学回收向更高选择性、更低能耗和更可持续的方向发展. 此外, 结合计算化学方法(如密度泛函理论)深入认识催化活性位点及反应机理, 并借助机器学习和数据驱动分析加速新型催化剂的筛选, 将成为提升分子筛催化效率的重要手段. 通过这些研究进展, 有望加速塑料闭环循环体系的构建, 为全球碳中和目标的实现提供有力支撑.

关键词: 塑料废弃物升级回收, 分子筛, 塑料精炼厂, 多相催化剂, 碳资源闭环

Abstract:

Current ever-accumulating plastic waste can be considered a significant carbon resource for energy conversion and chemical production. The development of new approaches for upcycling plastic waste through chemical degradation may enable circularity and promote closed-loop recycling of carbon sources compared to traditional recycling methods. Zeolite, a widely used solid acid catalyst with high industrial potential in petroleum and biomass refining, has been extensively studied for its role in transforming plastics. In this review, we present an overview of zeolite-based catalytic systems for the chemical recycling of plastic waste and discuss how zeolites could potentially contribute to the future development of a circular economy. To provide a comprehensive understanding, we begin with a brief introduction to zeolites, analyzing their key features and exploring their opportunities as well as challenges in processing plastic waste. Subsequently, we delve into the chemistry of catalytic cracking and tandem catalysis using zeolite-based catalysts on plastics. Overall, we emphasize the importance of intelligent catalyst design and lower-energy pathways to incentivize plastic upcycling while alleviating the burden caused by waste plastics.

Key words: Upcycling of plastic waste, Zeolite, Plastics refinery, Heterogeneous catalyst, Closed-loop of carbon resource