In the midst of the pandemic in 2021, we were throw away three million face masks per minute. Scientists sounded the alarm bells early, but the response to deal with has seen a lot of stuff find its way into our waterways.
In fact, an estimated 26,000 metric tons (28,660 tonnes) of pandemic-related non-degradable plastic waste – from medical supplies to online shopping packaging – has since spilled into the world’s oceans, posing a very real threat, alarming and urgent concern for marine habitats. .
A team of researchers from NYU Abu Dhabi (NYUAD) have developed a one-step, organic solvent-free hydrothermal process to convert polyethylene-based plastic bags and polypropylene-based surgical masks to carbon points.
carbon dots, a carbon-based nanomaterialhave attracted much research interest due to favorable attributes such as high electronic stability and mobility, and are used in biological imaging, environmental monitoring, chemical analysis, targeted drug delivery , the treatment of diseases and the fight against counterfeiting.
The global market value of carbon points is expected to reach US$6.412 billion by 2025, up from US$2.496 billion in 2019. But until now, turning plastic into carbon points was time-consuming and involved the use of toxic chemicals and solvents in the process. .
Now, in a breakthrough, the NYU team has developed a one-step oxidative hydrothermal approach to recycle polyethylene plastic bags and polypropylene surgical masks into 1-8nm fluorescent carbon dots. The process, which the researchers estimate to be slightly more expensive than current plastic recycling methods, is, however, cost effective when considering the market for carbon point technology. And it can even safely handle plastics contaminated with organic waste such as food scraps.
The researchers cost the new method about $3,670 per ton, while existing mechanical and chemical recycling methods cost nearly $1,000. However, the end product in carbon points, even with a conservative yield of 60%, would have a market value of around $1,800 per kg ($3,970 per pound) of plastic.
“The new method our team has developed is a cost-effective and safe method that can be easily implemented to significantly reduce the amount of harmful plastic released into our ecosystems,” said Khalil Ramadi, lead study author and assistant professor. of bioengineering at NYUAD.
Recycling plastic has given rise to innovative second uses for waste, including cycle paths, office furniture, portable speakers, floating green spaces, beautiful art and various types of fuel. Scientists have even used single-use plastic bags to create carbon nanotubes for use in technologies such as solar panels, computers and batteries.
However, the researchers believe this method may be able to provide the scale needed to solve the global single-use plastic problem.
The study was published in the journal Green chemistry.
Source: New York University Abu Dhabi