Wonder catalysts key to creating infinitely recyclable PET

IBM and Stanford University said work on a new chemical recycling method could reverse the polymerization process to regenerate monomers to their original state. The breakthrough could lead to new environmentally sustainable plastics which promise to significantly reduce waste and pollution, added the researchers.
The process, known as organocatalysis, uses biodegradable molecules made from renewable resources across a range of areas – including polyethylene terephthalate (PET) plastic bottles in the food and beverage industries.

The team said disposable PET plastics bottles were one the “most vexing environmental challenges” ​as it noted some 13 billion were discarded annually. While some PET is successfully recycled to a food contact standard, the technical challenges, cost and demand for the material have all been barriers to its large-scale development. Consequently, most recycled PET (rPET) means it isn’t used in food contact materials.

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Wonder catalysts​

But all this could be about to change if the research fulfils its potential.

“While plastics are recyclable, the resulting materials are limited to ‘second generation re-use’ only. This means the materials made from recycled plastic bottles are disposed in landfills,”​ said the researchers.

Dr Robert Allen, senior manager of chemistry and functional materials for IBM's Almaden research centre in Silicon Valley, said the group had developed “wonder catalysts”​ that were able to generate new materials that could allow PET bottles to be used more than once for their primary purpose.

“We have developed a catalyst that can go into this material and break it down very rapidly into building blocks,”​ he added. “We can take these building blocks and very easily build them back into PET material.”​

Vitally, the recycled plastic retains its original properties and are "ridiculously economical"​ to build it back up again, said Allen.

Scaling up​

IBM is currently working with researchers at King Abdulaziz City for Science and Technology (KACST) to work up the PET regeneration process from laboratory scale production towards a much greater commercial output, a company spokeswoman told FoodProductionDaily.com. The technology could be available within five years, she added if the research progresses well.

The catalysts are both biodegradable and biocompatible for use in the body or in landfill sites where they breakdown into harmless small molecules.

“The development of new families of organic catalysts brings more versatility to green chemistry and opens the door for novel applications, such as making biodegradable plastics, improving the recycling process and drug delivery,”​ said Josephine Cheng, IBM Fellow and vice president.