Ford, Rice University turn end-of-life auto plastic waste into new parts
And this is why Ford approached the Rice team, having become aware of its plastic-to-graphene process. Essentially, mixed ground plastic is blasted with a high voltage, and the sudden, intense heat of more than 2,500°C vaporizes the other elements, leaving behind turbostratic graphene. No solvents are required, and the energy requirements are not significant.
Ford sent the Rice team about 5 kilograms of muddy and wet mixed plastic waste from a vehicle shredding facility to test the process.
“We flashed it, we sent the graphene back to Ford, they put it into new foam composites and it did everything it was supposed to do,” Tour said. “Then they sent us the new composites and we flashed those and turned them back into graphene. It’s a great example of circular recycling.”
To test its effectiveness on end-of-life mixed plastic, a mixture of shredded plastic bumpers, gaskets, carpets, mats, seating and door casings from end-of-life F-150 trucks was ground into a fine powder, with no washing or pre-sorting. It was first flashed for 10–16 seconds under low current to make a highly carbonized plastic, accounting for about 30 percent of the initial mass; the rest was out-gassed or recovered as hydrocarbon-rich waxes and oils.
The carbonized plastic was then flashed under a higher current, with 85 percent converted to graphene and the remainder outgassed as hydrogen, oxygen, chlorine, silicon and trace metal impurities. A lifecycle analysis showed a substantial reduction in energy, greenhouse gas emissions and water use compared to other methods for making graphene.
The work has been published in the journal Communications Engineering.
