Turning over a new leaf?

What links the browning leaves of winter and the recycling of discarded plastic bottles? The answer is an enzyme that is found in those decomposing leaves that French scientists have used to decompose plastic bottles too. Furthermore, the French company Carbios have recently built a ‘reactor’ facility at Clermont-Ferrand which is about the size of a large van which can process around 100,000 ground up plastic bottles every 10-16 hours or about two-tons of ground up PET (polyethylene terephthalate). The process has already garnered interest from the likes of PepsiCo, L’Oreal and Nestle.  

So, how does the enzyme work?

It breaks down the polymers—long complicated molecules, into monomers—smaller, simple building blocks, separating the two major components of polyethylene glycol from terephthalic acid, in a matter of hours.  

One major advantage this enzymatic method offers over mechanical recycling is that the end product of plastic monomers is actually far closer to the original material manufacturers use with petroleum to make new bottles, than if they bought chopped-up plastic. Using the experience gained at this plant, Carbios will improve the upcoming industrial-size plant forecasted to open 2025.

As enzymatic recycling advances as a technology, a chance for more complex plastics like polypropylene, or those found in artificial clothing could eventually be tackled.