New Method Upcycles Plastics into Valuable Surfactants Used in Soap and Detergents

Researchers from Virginia Tech have developed a groundbreaking method to upcycle plastics into valuable chemicals called surfactants, which are used in the production of soap, detergent, and more. This method could provide a profitable and environmentally-friendly alternative to traditional plastic recycling.

The key to this discovery lies in the molecular similarity between polyethylene plastics and fatty acids, which are a chemical precursor to soap. Both materials are composed of long carbon chains, but fatty acids have an additional group of atoms at the end of the chain. Building on this similarity, the researchers hypothesized that it should be possible to convert polyethylene into fatty acids and ultimately produce soap.

To break down the long polyethylene chains into shorter chains efficiently, the research team developed a unique temperature-gradient thermolysis process. This process involved heating the plastic in a specially-built reactor at a high temperature and then quickly cooling it. After the thermolysis, the researchers obtained “short-chain polyethylene,” also known as waxes.

The next step was adding a few more key steps, including saponification, to transform the waxes into soap. With the help of experts specializing in computational modeling and economic analysis, the research team refined the upcycling process. The final result was the world’s first soap made from plastics.

Notably, this upcycling method can be applied to both polyethylene and another commonly used plastic, polypropylene. These plastics are found in various everyday consumer products like packaging, food containers, and fabrics. A major advantage of this upcycling technique is that it can simultaneously process both polyethylene and polypropylene, eliminating the need for separate sorting of these plastics.

Furthermore, the method has simple requirements: plastic and heat. While additional ingredients are needed to convert the waxes into fatty acids and soap, the initial transformation of the plastic is straightforward. This makes this upcycling method easily adaptable and potentially scalable for industrial applications.

The research was published in the journal Science and demonstrates a new route for plastic upcycling without the need for complex procedures or novel catalysts. This innovative approach has the potential to inspire future creative designs for upcycling procedures.