Chemical upcycling of polyethylene, polypropylene, and mixtures to high-value surfactants

• 成果类型: Article
• 署名作者: Xu, Zhen; Munyaneza, Nuwayo Eric; Zhang, Qikun; Sun, Mengqi; Posada, Carlos; Venturo, Paul; Rorrer, Nicholas A.; Miscall, Joel; Sumpter, Bobby G.; Liu, Guoliang
• 署名单位: Virginia Polytechnic Institute & State University; Shandong Normal University; United States Department of Energy (DOE); National Renewable Energy Laboratory - USA; United States Department of Energy (DOE); Oak Ridge National Laboratory; Center for Nanophase Materials Sciences; Virginia Polytechnic Institute & State University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-9858
• DOI: 10.1126/science.adh0993
• 发表日期: 2023-08-11
• 页码: 666-671
• 关键词: thermal-degradation; density polyethylene; waste; oxidation; valorization; temperature; pyrolysis; PRODUCTS; oxygen

摘要

Conversion of plastic wastes to fatty acids is an attractive means to supplement the sourcing of these high-value, high-volume chemicals. We report a method for transforming polyethylene (PE) and polypropylene (PP) at similar to 80% conversion to fatty acids with number-average molar masses of up to similar to 700 and 670 daltons, respectively. The process is applicable to municipal PE and PP wastes and their mixtures. Temperature-gradient thermolysis is the key to controllably degrading PE and PP into waxes and inhibiting the production of small molecules. The waxes are upcycled to fatty acids by oxidation over manganese stearate and subsequent processing. PP beta-scission produces more olefin wax and yields higher acid-number fatty acids than does PE beta-scission. We further convert the fatty acids to high-value, large-market-volume surfactants. Industrial-scale technoeconomic analysis suggests economic viability without the need for subsidies.