Researchers at the University of Leicester have made a major breakthrough in fuel cell recycling, developing a method to effectively separate valuable catalyst materials and fluorinated polymer membranes (PFAS) from catalyst-coated membranes (CCM).
This development addresses significant environmental concerns related to PFAS. PFAS, often referred to as "forever chemicals," are known to contaminate drinking water and pose serious health risks. The Royal Society of Chemistry is calling on the government to take action to reduce PFAS levels in the UK’s water supply.
High-power ultrasound can quickly separate valuable catalysts from the underlying polymer membrane in less than a minute. Image source: University of Leicester
Breaking down complex catalyst-coated membranes
Fuel cells and water electrolysers are essential components of hydrogen energy systems that power cars, trains and buses, and they rely on catalytic materials (CCMs) containing precious platinum group metals. However, the strong adhesion between the catalyst layer and the PFAS membrane makes recycling difficult.
Researchers in Leicester have developed a scalable method that uses organic solvent soaking and water ultrasound to effectively separate these materials, revolutionizing the recycling process.
High-power ultrasound can quickly separate valuable catalysts from the underlying polymer membrane in less than a minute. Image source: University of Leicester
Dr Jake Yang from the School of Chemistry at the University of Leicester said: "This method is simple and scalable. We can now separate PFAS membranes from precious metals without the use of harsh chemicals, which will revolutionize the way fuel cells are recycled. Fuel cells have long been hailed as a breakthrough technology for clean energy, but the high cost of platinum group metals has been seen as a constraint. A circular economy for these metals will bring this breakthrough technology closer to reality."
Ultrasonic blades reduce recycling time to seconds
Building on this success, follow-up research introduced a continuous layering process using a custom-made blade ultrasonic generator that uses high-frequency ultrasonic waves to split the membrane to accelerate recycling.
High-power ultrasound can quickly separate valuable catalysts from the underlying polymer membrane in less than a minute. Image source: University of Leicester
The process creates bubbles that collapse under high pressure, meaning the precious catalyst can be separated out within seconds at room temperature. This innovative process is both sustainable and economically viable, paving the way for widespread application.
This ground-breaking research was carried out in partnership with Johnson Matthey, a global leader in sustainable technologies. Such industry-university-research collaborations highlight the importance of joint efforts in driving technological advancement.
High-power ultrasound can quickly separate valuable catalysts from the underlying polymer membrane in less than a minute. Image source: University of Leicester
Ross Gordon, principal research scientist at Johnson Matthey, said: "The development of high-intensity ultrasonic separation catalyst membranes will revolutionize the way we recycle fuel cells. Johnson Matthey is proud to work together to develop these pioneering solutions to accelerate the adoption of hydrogen while making it more sustainable and economically viable."
As demand for fuel cells continues to grow, this breakthrough contributes to the circular economy by enabling efficient recycling of critical clean energy components. The researchers' efforts not only help fuel cell technology achieve a greener, more economical future, but also address pressing environmental challenges.
Compiled from /ScitechDaily