In late September, Carbios, a French startup, opened a demonstration plant in central France to test this idea. The facility will use enzymes to recycle PET, one of the most common single-use plastics and the material used to make most beverage bottles.
Carbios’s new reactor measures 20 cubic meters—around the size of a cargo van. It can hold two metric tons of plastic, or the equivalent of about 100,000 ground-up bottles at a time, and break it down into the building blocks of PET—ethylene glycol and terephthalic acid—in 10 to 16 hours.
The company plans to use what it learns from the demonstration facility to build its first industrial plant, which will house a reactor about 20 times larger than the demonstration reactor. That full-scale plant will be built near a plastic manufacturer somewhere in Europe or the US, and should be operational by 2025, says Alain Marty, Carbios’s chief science officer.
Carbios has been developing enzymatic recycling since the company was founded in 2011. Its process relies on enzymes to chop up the long chains of polymers that make up plastic. The resulting monomers can then be purified and strung together to make new plastics. Researchers at Carbios started with a natural enzyme used by bacteria to break down leaves, then tweaked it to make it more efficient at breaking down PET.
Carbios estimates that its enzymatic recycling process reduces greenhouse gas emissions by about 30% compared to virgin PET. Marty says he expects that number to increase as they work out the kinks.