Pile of plastic bottle Source: Julia Joppien on Unsplash
A team of researcher from the University of Oxford developed a simple one-step microwave-initiated catalytic process for a rapid deconstruction of common bulk plastics like plastic bottles, milk containers and other plastic packaging into hydrogen and high-value carbon materials.
The study states that the process extracts almost 97% of the hydrogen from plastic waste in about 20 seconds.
It is considered as a potential and pragmatic approach to tackle the mammoth issue of plastic waste faced by the planet.
Though it is a significant achievement, the researcher believes that there is a need of energy minimization and improvement of applicability and sustainability credentials.
The research team crushed real-world plastic waste of milk containers, plastic bags food wraps into small pieces using kitchen blender. Later, it was mixed with iron based catalyst in a typical weight ratio of 1:1. Once the mixture was blasted with microwave power of 1000 watts, catalyst created hot spots in the plastic and stripped out the hydrogen – recovering 97 per cent of the gas in the plastic.
The solid material left over was almost exclusively carbon nanotubes. The single-step approach has the advantage of just heating the catalyst, not all of the plastic, resulting in less energy use, as the plastic does not absorb microwaves.
There are other methods to convert plastic waste using solar-driven reforming. It is considered as low energy means to turn waste into hydrogen. Moreover, there is also the development of commercial facilities in the UK. It is expected to treat up to 35 tonnes of unrecyclable plastics a day and using it to create a local source of hydrogen.
The article is published in Nature Catalysis Journal and can be accessed here.