Smartphones, tablets, laptops and electric cars may help the environment by being rechargeable, but they’re not doing it many favours when it comes to recycling.
The batteries, magnets and motors used inside them contain rare earth metals, such as lanthanum, neodymium and dysprosium, which are expensive and time-consuming to separate and process so they can be reused elsewhere.
To make matters worse, extricating the metals from the gadgets can produce harmful waste. As a result, rare earth metals are rarely recycled – currently the rate stands at around 5 per cent.
But in February 2021, a team of material scientists from Iowa State University in the US Department of Energy’s Ames Laboratory submitted a patent application for a new method that would make recycling such metals easier, cheaper and cleaner.
To typically recycle such metals, you’d have to crush the parts containing them into a fine powder, then use chemicals to convert and separate the desired elements out of the alloys. It’s a method that not only requires high temperatures and a lot of time, but also uses strong acids that lead to dangerous waste.
The new method being proposed involves adding either ammonium salt or iron III salt to the parts being recycled. The parts are then ground down and dropped into water, which can be at room temperature, to begin the process of separation that can take as little as two days.
Read more about recycling:
- Poo power and rubbish bricks: 8 ingenious projects forging a trash-free future
- Is it possible to recycle plastics an infinite number of times?
The team behind the process say it can be used to extract 16 of the 17 rare earth metals, as well as nickel and cobalt, that are found in the batteries and magnets used in electronic devices and vehicles. What’s more, the salts used in the new extraction process are abundant, inexpensive and can be recovered and reused afterwards.
An increasing shift towards electric vehicles is necessary if we are going to hit emissions targets in order to combat climate change, which means the demand for rare earth metals is set to grow rapidly over the next decade.
Since mining the metals is harmful to the environment, the need for an effective and efficient method of recycling them with as little environmental impact as possible is vital. The method being proposed by the Iowa State University and Ames Laboratory scientists might just be the answer.
Reader Q&A: How are batteries recycled?
Asked by: Dileep Bagnall and Anna Daca, via email
In the UK, the most widely recycled battery is the lead-acid type that we use in our cars. These are broken apart in a hammer mill, the sulphuric acid drained off, and the lead and plastic separated in a water bath. Once collected, these are melted and used to form new batteries, while the acid is converted into industrial chemicals or water.
A similar mechanical separation process is used to extract and reuse the zinc, manganese, steel and other components from alkaline batteries (such as AA and AAA).
On the other hand, current methods for recycling lithium batteries are inefficient – it’s cheaper to make new batteries than recover the lithium and cobalt from old ones. This is expected to change with the growing popularity of electric vehicles, which will help to fuel new research into lithium battery recycling methods.
- Why do batteries explode?
- Why can I get more power out of a dying battery by taking it out then reinserting it?