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

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 ~80% conversion to fatty acids with number-average molar masses of up 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 ꞵ-scission produces more olefin wax and yields higher acid-number fatty acids than does PE ꞵ-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.

 
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Award ID(s):
1752611
NSF-PAR ID:
10499302
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science
Volume:
381
Issue:
6658
ISSN:
0036-8075
Page Range / eLocation ID:
666 to 671
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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