American Scientists Discover Method to Turn Used Plastics into Soap.
According to The Guardian, plastic has chemical properties similar to fatty acids, which are one of the main components of soap. Guoliang Liu, an associate professor of chemistry at Virginia Polytechnic Institute and the author of a study published in the journal Science, stated that this similarity could allow us to transform polyethylene into fatty acids, which can then be used to produce soap. The challenge lies in the large molecular size of plastics, which can consist of around 3,000 carbon atoms, while fatty acids are significantly smaller.
This will be the world’s first soap made from plastic. (Illustrative image).
The idea of turning plastic into soap came to Liu quite unexpectedly. He shared, “It was Christmas Eve. I was warming myself by the fireplace.” He wondered if burning plastic might occur in a similar manner to burning wood, which produces smoke made up of smaller wood particles.
“Wood primarily consists of polymers like cellulose. Burning wood breaks down these polymers into shorter chains, transforming them into small gas molecules before fully oxidizing into carbon dioxide. If we break down synthetic polyethylene molecules similarly but stop the process before they completely degrade into small gas molecules, we could obtain short-chain polyethylene-like molecules,” he explained.
Liu and his colleagues constructed a reactor resembling an oven, designed to safely burn plastic. The temperature at the bottom of the oven is hot enough to break the polymer chains, while the temperature above is low enough to prevent them from degrading too quickly.
The scientists collected the remaining compounds and discovered short-chain polyethylene, a type of wax. They then proceeded to transform this wax into soap.
“This is the first soap in the world made from plastic. It has a very unique color,” Liu said.
Liu’s method is applied to polyethylene and polypropylene, the two most common types of plastic today. These account for about half of the global plastic waste, approximately nearly 200 million tons each year. Worldwide, over 80% of plastic waste ends up in landfills, while only about 10% is recycled.
One of the advantages of this new method is that it works on expired plastics, which are typically non-recyclable through conventional means.
“Plastic pollution is a global challenge. It is one of the major issues our society faces. There needs to be a collective effort between the research and industrial communities. The best way to prevent plastic pollution is to minimize plastic use,” he stated.
