Wil Sillen's post

Scientists develop simple way to recycle polyester
By: Hidde Middelweerd
Polyester is one of the most widely used textiles in the world, but recycling it is still a difficult story. Scientists at the University of Copenhagen may have found a simple solution for this. The necessities: heat, salt and a solvent.

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Polyester is a mix of plastic and cotton and countless products can be made from it. From curtains and sofas to all kinds of clothing. One problem: it is difficult to separate and recover the cotton and plastic at the end of its life. Current recycling methods are mainly able to recover the plastic, whereby the cotton is lost.

Partly as a result of this, recycling of polyester only takes place in dribs and drabs. More than 60 million tons of polyester products are produced each year and only 15 percent are recycled. The rest ends up in the landfill or in the incinerator.

Polyester recycling
Chemists at the University of Copenhagen may have a solution for that. They came up with a recycling method that is simple and cheap and is able to recover both the cotton and the plastic. “With our technology, we can break down the plastic (a polymer, ed.) in polyester into the building blocks it is made of (monomers, ed.). This is a mild process, which also keeps the cotton intact. And all in a simple and environmentally friendly way,” says Yang Yang, lead author of the study. “This could be a game changer.”

The scientists first cut a polyester product into small pieces. They then put it in a container along with stag horn salt (also called ammonium carbonate) and a solvent. The container is heated to 160 degrees Celsius and then left to rest for 24 hours. The result is a liquid in which the plastic and cotton fibers are separated from each other.

The stag horn salt plays an important role in that process. When heated, it disintegrates into ammonia, CO2 and water. The combination of ammonia and CO2 serves as a catalyst that breaks down the plastic into polyester, but leaves the cotton alone.

Scaling up
The recycling method has currently only been tested on a laboratory scale, but the researchers involved expect the process to be scalable. They are already in talks with recycling companies to test the method on an industrial scale.
  • Kevin

    40 w

    This is absolutely phenomenal

    • Ajema Lydiah

      40 w

      The best way of reducing pollution

      • Jengaj John

        40 w

        This is a much more sustainable process, making it better for the environment.

        • mercy nduta

          40 w

          A fantastic option when it comes to protecting our environment.

          • Komu Daniel

            40 w

            This is incredible

            • Gorffly mokua

              40 w

              Impressive development.

              • Munene Mugambi

                40 w

                Glad to see recycling efforts at the forefront

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