[EN] Chemical upcycling technologies are emerging as the most viable to combat plastic waste accumulation. Among them, catalytic pyrolysis is very promising as it is feedstock agnostic. However, the high energy demand associated with pyrolysis can lead to significant carbon dioxide production. Here, we demonstrate that coupling microwave heating with suitable solid acid promoters in a slurry reactor coupled with a distillation unit can overcome the energy-related challenge of conventional pyrolysis, by operating at modest temperatures (350-375 degrees C), enhancing transport, and furnishing high yields of olefins (-88 %) in seconds, with medium-sized olefins (>75 %) composing a significant fraction. Reduced thermal gradients minimize coke formation, further improving the performance. Techno-economic analysis and life cycle assessment indicate the potential of the technology.

This work was supported as part of the Center for Plastics Innovation, an Energy Frontier Research Center, funded by the U.S. Dept. of Energy, Office of Science, Office of Basic Energy Sciences, under Award Number DE-SC0021166. The microwave instrumentation and computations were supported by the Department of Energy's Office of Energy Efficient and Renewable Energy's Advanced Manufacturing Office under Award Numbers DE-EE0007888-8.3 and DE-EE0007888-9.5, respectively, and the State of Delaware. This research used instruments in the Advanced Materials Characterization Lab (AMCL) and the W. M. Keck Center for Advanced Microscopy & Microanalysis at the University of Delaware. The authors are grateful to Brandon Vance for his valuable assistance with the synthesis of WZr catalysts.