Pyrolysis plants that turn plastic waste into hydrocarbon feedstocks that can be recycled into plastic are supported by major chemical industries. By using high temperatures and oxygen-free atmospheres, plastics are broken down into combinations of smaller molecules known as pyrolysis oils.
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However, the cover story chemical engineering newsAn independent news source for the American Chemical Society says there are criticisms of this approach.
Proponents of pyrolysis argue that their method can compensate for the limitations of conventional recycling.
But according to senior editor Alex Turo, environmentalists have not yet been persuaded, and more and more states, including California, are not considering pyrolytic recycling.
Critics say pyrolysis plants cannot accept mixed plastic waste as advertised.
A second concern is that pyrolysis is really just incineration. Scale is yet another matter. About 120,000 tons of capacity are currently running in the US in pyrolysis and other chemical recycling processes, a small fraction of his 56 million tons of plastic production expected in North America in 2021. .
Industry leaders claim that they are more active in using pyrolysis on a larger scale than ever before and are more focused on recycling than before. To increase capacity, companies are constructing larger buildings than before.
Strategies such as using catalysts and sorbents to filter particulate matter and remove the most reactive compounds from feed streams are causing some companies to accept more mixed waste. .
The development of infrastructure by petrochemical companies to process pyrolysis plant by-products, along with the licensing of the technology to other parties seeking to enter the market, clearly reflects a growing interest in pyrolysis. increase.
How technology works in the real world will greatly affect how the public perceives the plastics industry.