Right now, only about 15% of all plastics<\/a> worldwide are collected for recycling each year. Researchers have been trying since the 1990s to find new ways to break down plastics in the hopes of recycling more of them. Companies and researchers have worked to develop enzymatic processes, like the one used at Carbios, as well as chemical processes<\/a>, like the method used by Loop Industries<\/a>. But only recently have enzymatic and chemical processes started to go commercial. <\/p>\n\n\n\n Carbios\u2019s new reactor measures 20 cubic meters\u2014around 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\u2014ethylene glycol and terephthalic acid\u2014in 10 to 16 hours.<\/p>\n\n\n\n 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<\/a>, Carbios\u2019s chief science officer.<\/p>\n\n\n\n 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.<\/p>\n\n\n\n Carbios estimates that its enzymatic recycling process reduces greenhouse gas emissions by about 30% compared to virgin (newly created, non-recycled) PET. Marty says he expects that number to increase as they work out the kinks.<\/p>\n\n\n\n In a recent report<\/a>, researchers estimated that manufacturing PET from enzymatic recycling could reduce greenhouse gas emissions between 17% and 43% compared to making virgin PET. The report wasn\u2019t specifically about Carbios, but it\u2019s probably a good estimate for its process, according to Gregg Beckham<\/a>, a researcher at the US National Renewable Energy Laboratory and a co-author of the report.<\/p>\n\n\n\n While developing new enzymes has been a major focus of new research and commercial efforts, other parts of the process will determine how efficient and cost-effective the technology will be, says Beckham, who leads a consortium<\/a>on new plastic recycling and production methods.<\/p>\n\n\n\n \u201cIt\u2019s all the less glamorous stuff,\u201d Beckham says, like getting the plastic into a form that the enzymes can efficiently break down or separating what the enzymes spit out, that can take a lot of energy and time, and drive up emissions and costs.<\/p>\n\n\n\n Carbios\u2019s product is about twice as expensive as virgin PET, Marty says. By comparison, mechanically recycled PET is only about 50% more expensive than virgin. Marty points out that Carbios\u2019s PET would still only cost about two cents for a small, clear plastic bottle, which he argues is a relatively small expense for manufacturers.<\/p>\n\n\n\n![\"\"](\"https:\/\/wp.technologyreview.com\/wp-content\/uploads\/2021\/10\/IMGL6022.jpg?w=3000\")