With an estimated 100 million metric tons of non-biodegradable polyethylene plastic produced every year — not to mention other popular plastics — it’s no wonder that we have a plastics waste problem. From bags to bottles, there’s a lot of it out there sitting in landfills and floating in our oceans, so a new technique to transform that plastic into a usable, rather clean fuel has exciting ramifications.
Although there are methods of eliminating plastics like polyethylene from the world, they often require high heat and can lead to a messy breakdown into relatively useless compounds. The idea behind the joint U.S.-China team of Xiangqing Jia, Chuan Qin, Tobias Friedberger, Zhibin Guan and Zheng Huang is to make it possible to break down the plastic in a low-energy fashion and to produce something useful at the other end.
Using a technique of catalytic breakdown developed by Alan Goldman and Zheng Huang known as tandem catalytic cross alkane metathesis, the team was able to take polyethylene and strip it down to much simpler hydrocarbons, effectively creating a diesel fuel, with some additional waxes, which can be used in industrial settings, according to the Los Angeles Times.
The precise process for the technique, which was detailed in Science Advances, is a lengthy one, but it involves utilizing catalysts like an iridium-based compound to break down the chains into something much more manageable.
The process could not only provide a means of recycling a material that was previously hard to dispose of, but could also turn that material into fuel, which would provide a financial incentive. Such an advance could also potentially help encourage the cleaning of the world’s oceans of plastics.
The hope moving forward is that the researchers can turn the technique into one that can operate at a larger, industrial scale.