The most common plastic, polyethylene, are the kind of plastic to be the hardest to break down, yet several companies and institutions have working in plastic wastes reduction and it seems that there are methods underway.
A team of Chinese chemists developed a method for degrading polyethylene and transform it into liquid fuel.
Conventional methods in the process of burning polyethylene at a high temperature includes dumping, burning or pyrolysis. But pyrolysis has many drawbacks since it is being energy intensive, polluting and just hard to degrade compared to polyethylene itself.
The study was published in Scientific Advances which details a new approach. In the method stated that polyethylene degrades at temperature as low as 150 degrees Celsius. In this method, it includes adding an organometallic catalyst which is a small, commercially available organic molecule-doped with the metal iridium to the reaction.
The catalyst weakens the bonds that is responsible for polyethylene’s stiff structure, quickly moving its breakdown into a liquid product. The liquid is easier to control and can be used a diesel fuel. It has been tested on small samples of bottles, food packaging and plastic bags.
But according to the project lead, Zheng Huang, in an interview with Gizmodo, the current process works in a ratio of 30 to one. And the world will need 10 thousand to one, or a million to one.
Iridium will also be the problem because it is a rare and precious metal and it needs cheaper alternative for the method to be adapted.
“We think that the future potential is there—as long as we can improve the efficiency and reduce the cost of the iridium,” Huang said.
“Hopefully, very soon we can scale up the process from gram scale in the lab to kilogram and even ton scale.” Huang added.