Chinese scientists have made a crucial breakthrough in the world of plastics after discovering how to convert polyethylene, the world’s most common plastic, into liquid fuel using an energy efficient process.
Because of the inert nature of polyethylene, it takes a very long time for it to breakdown in the environment. This is especially problematic when it comes to plastic pollution in the ocean — by 2050, Earth’s oceans will hold more plastic than fish by weight, according to a World Economic Forum study.
Scientists do know how to break down polyethylene through a process called pyrolysis, but it requires extreme heat (752 degrees Fahrenheit) and energy and the resulting byproducts can’t be easily controlled.
Zheng Huang, an organic chemist at the Chinese Academy of Sciences, discovered that with the use of petroleum ether, a common laboratory solvent, polyethylene can be broken down into diesel fuel or wax in lower temperatures. His findings were recently published in the journal Scientific Advances.
The study explains:
“To the best of our knowledge, the degradation of real-world postconsumer PEs under such mild reaction conditions is unprecedented. Featuring high efficiency, mild reaction conditions, and fine control of degradation products, this method shows distinct advantages over traditional pyrolysis processes.”
The process has so far been successfully tested on plastic bags, bottles and food packaging. Now, the challenge of scaling the process remains, and if possible, it could make a considerable reduction in plastic pollution. Huang explained to Gizmodo:
“Our products are much cleaner than those obtained by conventional [combustion] methods.
“We think that the future potential is there, as long as we can improve the efficiency. Hopefully, very soon we can scale up the process from gram scale in the lab to kilogram and even ton scale.”