Low-temperature upcycling of polyolefins into liquid alkanes via tandem cracking-alkylation

• 成果类型: Article
• 署名作者: Zhang, Wei; Kim, Sungmin; Wahl, Lennart; Khare, Rachit; Hale, Lillian; Hu, Jianzhi; Camaioni, Donald M.; Gutierrez, Oliver Y.; Liu, Yue; Lercher, Johannes A.
• 署名单位: Technical University of Munich; Technical University of Munich; United States Department of Energy (DOE); Pacific Northwest National Laboratory; East China Normal University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-11720
• DOI: 10.1126/science.ade7485
• 发表日期: 2023-02-24
• 页码: 807-811
• 关键词: halometallate ionic liquids; coordination-complexes; polyethylene; isobutane; catalysis; zeolite; waste

摘要

Selective upcycling of polyolefin waste has been hampered by the relatively high temperatures that are required to cleave the carbon-carbon (C-C) bonds at reasonably high rates. We present a distinctive approach that uses a highly ionic reaction environment to increase the polymer reactivity and lower the energy of ionic transition states. Combining endothermic cleavage of the polymer C-C bonds with exothermic alkylation reactions of the cracking products enables full conversion of polyethylene and polypropylene to liquid isoalkanes (C6 to C10) at temperatures below 100 degrees C. Both reactions are catalyzed by a Lewis acidic species that is generated in a chloroaluminate ionic liquid. The alkylate product forms a separate phase and is easily separated from the reactant catalyst mixture. The process can convert unprocessed postconsumer items to high-quality liquid alkanes with high yields.