Yale researchers have developed a new, efficient, and low-cost way to convert plastic waste into fuels and valuable chemicals using a catalyst-free pyrolysis method. Pyrolysis breaks down plastics by heating them without oxygen. Traditional pyrolysis methods rely on expensive catalysts that degrade over time, or else suffer from low conversion rates without catalysts.
Their innovation is a 3D-printed, electrically heated carbon reactor with a unique structure of progressively smaller pores (from 1 mm to 200 nm). This hierarchical pore design controls the breakdown of plastic molecules by preventing large molecules from passing through before fully decomposing, and also manages temperature to avoid issues like coking.
Testing on polyethylene plastic showed a record-high conversion yield of about 66% into useful chemicals for fuels. A more scalable version made from commercial carbon felt also achieved a strong 56% conversion.
This catalyst-free, energy-efficient system offers a promising practical solution to turn plastic waste into valuable materials, potentially impacting how plastic pollution is managed.