Scientists have developed a novel method that uses enzymes found in laundry detergents for recycling single-use bioplastics in disposable items such as coffee cups and food containers. The method, described in the journal Cell Reports Physical Science, uses the enzymes to “depolymerise”-or break down-landfill-bound bioplastics into soluble fragments within just 24 hours.
The problem with ‘green’ plastics
Current rates of plastic production outstrip our ability to dispose of it sustainably. According to non-profit Environmental Action, it is estimated that in 2023 alone more than 68 million tonnes of plastic globally ended up in natural environments due to the imbalance between the huge volumes of plastics produced and our current capacity to manage and recycle plastic at the end of its life. A recent Organisation for Economic Co-operation and Development (OECD) report predicted that the amount of plastic waste produced worldwide is on track to almost triple by 2060, with around half ending up in landfill and less than a fifth recycled.
While bioplastics-derived from biological sources such as corn starch, cassava or sugarcane-are seen as a more sustainable choice by consumers, current methods of bioplastics production are costly and compete with food-based agriculture for use of land, the researchers said. Mechanical recycling methods are inefficient, generate CO2 and are incapable of producing high-quality reusable materials. These “green” plastics primarily end up in landfill after just one use, causing many retailers to revert to using oil and fossil-based materials.
The solution: laundry enzyme
The research offers a widespread recycling solution for single-use PLA plastics, as the scientists at King’s College London, UK, found that in a further 24 hours at a temperature of 90 degrees Celsius, the bioplastics break down into their chemical building blocks. Once converted into monomers-single molecules-the materials can be turned into equally high-quality plastic for multiple reuse, according to the researchers.
The process achieves full degradation of the bioplastic polylactic acid (PLA) in an approach that is 84 times faster than the 12-week-long industrial composting process used for recycling bioplastic materials. The speed at which the bioplastics break down using this new method could revolutionize plastic production, offering an efficient, scalable and sustainable blueprint for recycling single-use bioplastics.
A significant breakthrough in the recyclability of single-use bioplastics, the research opens up the opportunity for a sustainable, circular economy that stamps out the production of fossil-based plastics and tackles the huge volume of plastic waste that ends up in landfill and natural environments.
Dr. Alex Brogan, Lecturer in Chemistry at King’s College London, said, “The inspiration for this project came from a problem with bioplastics used in medical and surgical products degrading in the body.”
Conclusion
The novel method of chemical recycling using enzymes from laundry detergents offers a new hope for recycling single-use plastics within 24 hours. The method is faster, cheaper and more environmentally friendly than current methods of bioplastics production and disposal. The research has implications for creating a circular economy that reduces plastic waste and greenhouse gas emissions.