Plastic Bottles’ Future Is Aviation Fuel? Yale’s New Technology Turns Plastic Waste Directly Into High-Value Chemicals

The director of the Yale Center for Materials Innovation stated: "Catalysts are not only extremely expensive, but they also have issues with service life—they eventually fail for various reasons." Researchers used 3D printing technology to fabricate an electrically heated reactor composed of carbon columns with three segments of decreasing pore size.

Liangbing Hu (left) and Shu Hu, scientists from Yale University

The first section has a pore size of 1 millimeter, the second section 500 micrometers, and the third section only 200 nanometers. This stepwise reduction in pore size creates a "gate" mechanism: it ensures that large molecules cannot enter the next reaction section before being fully pyrolyzed. This design also allows for precise control of the reactor temperature, preventing coking and efficiency losses caused by overheating.

The research team tested the 3D-printed reactor using polyethylene samples in a laboratory environment. The results showed a yield of 65.9% ± 5.2%, with a selectivity of up to 80.8% for C8–C18 hydrocarbons, which are commonly used as precursors for aviation fuels.

Researchers at Yale University have designed a pyrolysis method consisting of a carbon column reactor with three decreasing apertures to convert plastic waste into usable chemicals.

The team also attempted to use commercial carbon felt materials to replace 3D-printed structures, in order to validate reactor designs with greater potential for large-scale application. Although this design could not precisely control the porosity, it still achieved a useful chemical yield of 56%.

An assistant professor of chemistry and environmental engineering at Yale University pointed out: "These results are very encouraging, demonstrating the great potential of putting this system into practical use and providing a practical strategy for converting plastic waste into high-value materials."

The research titled "Pore Modulated Pyrolysis for Selective Electrochemical Upcycling of Polyethylene" has been published in the journal Nature Chemical Engineering.