Upcycling Low-Value Plastics

Teresa Madaleno

Researchers at Northwestern University’s Argonne National Laboratory in Illinois have discovered a way to take low-value plastics and transform them into high quality liquid products.

The research team is thrilled to report that what is usually destined for the dump, has the potential to be turned into lubricants, detergents and cosmetics. One of the researchers recently told SciTech Europa that the discovery has ”broad implications for developing a future in which we can continue to benefit from plastic materials but do so in a way that is sustainable and less harmful to the environment and potentially human health.”

There are many different steps we can take to reduce the amount of plastics we consume but it would be difficult to replace all plastics. Today, there are many experts around the world looking for ways to upcycling plastics. In this particular case, the researchers at the Argonne National Lab were looking to recoup the energy that holds bonds together by catalytically converting the polyethylene molecules into commercial products. They used platinum nanoparticles as a catalyst, putting them on perovskite nanocubes. Perovskite is a yellow or black mineral that consists mostly of calcium titanate. Under moderate pressure and temperature, the catalyst split the plastic’s carbon-carbon bond and produced liquid hydrocarbons.

The research has been published in the Journal ACS Central Science.

This type of upcycling should not be confused with down-cycling, which is plastics being melted and reprocessed into low-value materials as opposed to high-value materials. Low value means the outcoming product is not structurally as strong as the original material. An example of down-cycling is plastic bottles that have been made into a park bench.

When left in landfills, plastics don’t degrade. This is because they have strong carbon-carbon bonds. They tend to break down into small pieces called microplastics. For years people have viewed these strong bonds as a problem but those who are thinking beyond the surface, like the researchers at Argonne National Laboratory, see this as a great opportunity.