Scientists develop a simple method to recycle PET plastic

Scientists from Japan and Malaysia have discovered an easy way to convert a common plastic, PET, back into its original form using iron and alcohol. This method is particularly effective as it can selectively recycle PET from mixed plastics and textiles. They have detailed their findings in the journal Industrial Chemistry and Materials.

Although PET water bottles can be recycled by melting and reshaping, the quality of the plastic often decreases, and it requires careful separation from other materials. This process doesn’t work well with mixed waste or polyester textiles, especially those made from blends like poly-cotton, as separating individual fibers is challenging.

The newly developed method operates at temperatures below 200°C, which is considered low by industrial standards, and only requires alcohol and an inexpensive iron-based catalyst.

In their study, the were able to produce nearly pure monomers, specifically diethyl terephthalate and ethylene glycol, which can be used to make high-quality PET or other materials. The ferric chloride catalyst proved to be particularly effective, so the researchers tested it on a textile that was 65% PET and 35% cotton. Within 16 hours, they successfully separated the monomers from the textile, leaving behind pure cotton and pure monomers.

They also demonstrated that this method could selectively remove PET from textile blends containing different plastics. The researchers noted that ferric chloride is an affordable catalyst already widely used in various industries. They believe that this method could lead to a cleaner chemical recycling process using an easily accessible catalyst. The team is now exploring whether they can achieve similar results under even milder conditions.