As cars become more environmentally friendly, scientists are looking into alternative types of fuel. A team of researchers at Swansea University have developed a way of turning plastic waste into hydrogen. The process involves adding a light-absorbing material to plastic, putting it in a solution and exposing it to the sun.
The hope of Dr Mortiz Kuehnel and his team is that recycled plastic could be used as car fuel. Kuehnel believes that recycled plastic would be a lot to cheaper and be far better for the environment.
“There’s a lot of plastic used every year – billions of tonnes – and only a fraction of it is being recycled. We are trying to find a use for what is not being recycled. PET (polyethylene terephthalate) is the plastic most plastic bottles are made from and this can be recycled, but in practice it is not always recycled.”
“There are a number of reasons for this – one is that recycling in general isn’t cheap, so it’s easier to burn stuff or throw it on a landfill. But even if you do recycle it, it needs to be very pure – so only PET, nothing else mixed in with it…and it has to be clean, no grease, no oil. Potentially you need to wash it which is very expensive, and even if you do all of that, the plastic you get isn’t always a nice virgin material.”
What goes into the process?
- Plastic is cut and the surface is rubbed until its rough
- A material called a photocatalyst is added in order to absorb sunlight
- The photocatalyst is placed into an alkaline solution
- Sunlight is shone onto the solution to produce hydrogen
Kuehnel also spoke about the simplicity of the process. “It’s not very picky. It can degrade all sorts of waste. Even if there is food or a bit of grease from a margarine tub, it doesn’t stop the reaction. It makes it better. The process produces hydrogen gas. You can see bubbles coming off the surface.”
The research has received funding through the Engineering and Physical Sciences Research Council. It may take a few years for the project to be carried out on a mass scale, but recycled plastic does have a lot of potential as fuel.
