New Technology Can Upgrade Old Car Plastics Into Graphene

Plastic waste from end-of-life cars accounts for 1 billion tons of total plastic waste in landfills, with 200-350 kilograms of plastic per car. Such materials are difficult to reuse for a variety of reasons. Many of these materials, for example, are engineered plastics that can't be recycled with existing technology, and traditional recycling methods require separating different types of plastic, which is expensive to recycle.

Recent studies have shown that it is possible to turn waste plastics into graphene, a valuable material ($60,000 - $200,000 per ton) with practical properties such as high electrical conductivity and high thermal and chemical stability. The research could be a possible way to recycle automotive plastics into graphene, which is sometimes used as an additive in some automotive plastics to improve strength and noise absorption.

The rice University team demonstrated how to turn used car plastic into high-quality graphene using an energy-saving technology called Joule flash. The technology uses an electric current to heat carbon to turn it into graphene, using only low-cost facilities and no need to separate or sort the plastic, solvents, furnaces or water.

The researchers shred bumpers, gaskets, carpets, MATS, seats and door frames from a Ford F-150 pickup truck and demonstrated the general steps of the process. They used the recycled graphene to enhance new automotive plastics and found that they performed as well as ford's new graphene-containing plastic composites.

The team then reheated the graphene/plastic composite from waste using joule flash technology to produce more graphene. In addition, they found that joule flash had lower energy requirements, global warming, and water consumption than conventional graphene production methods.