Graphene can function as an efficient sieve for hydrogen isotopes. Image credit: University of Manchester

Graphene-based membranes have the potential to reduce energy and environmental costs incurred by the nuclear power sector, according to researchers from the University of Manchester, UK.

The production of heavy water needed by the nuclear industry to generate clean energy is highly energy-intensive. Producing just 1 kg of heavy water consumes enough energy to power an average American household for an entire year.

Graphene has the potential to effectively separate sub-atomic particles, making this process more efficient and cost-effective. The researchers developed fully scalable prototype membranes and demonstrated the isotope separation in pilot scale studies. They found that the high efficiency of the separation would allow for a significant reduction of the input amount of raw isotope mixtures that needs to be processed. This reduces both capital costs and the energy requirements.

A membrane based on 30 m² of graphene, a readily accessible amount, could provide a heavy-water output comparable to that of modern plants.

Over 100x less energy to produce heavy water is estimated to be required compared to competing technologies—even larger energy savings are anticipated for tritium decontamination. The development could lead to the reduction of carbon dioxide emissions associated with heavy water production by up to one million tpy.