Recycling deuterated water at ISIS to reduce costs and environmental impact
21 May 2026 - Rohini Gupta
A recovery process to improve efficiency, reduce costs and support research has been developed, led by James Tellam & June McCorquodale from the ISIS Deuteration Facility along with help from the wider support laboratories group.
Recycling deuterated water (D₂O) is becoming increasingly important for neutron research facilities, especially at the ISIS Neutron and Muon Source, where large quantities are used every year. On average, around 250 litres are required annually. Producing D₂O is highly energy intensive and rising inflation has significantly increased costs, with prices now reaching about £2000 per kilogram, which is more expensive than silver. Alongside this, long lead times of over six months make it difficult to plan and maintain a reliable supply. While some facilities tightly control access to D₂O, ISIS provides to users without requiring formal requests, which makes managing stock even more challenging. This situation highlights three key concerns: the importance of reducing environmental impact, the need to reduce costs and the difficulty of maintaining a consistent supply.
So far, the results have been very encouraging, with around 130 litres of D₂O successfully recycled.
June McCorquodale
Where did the idea come from?
The idea of recycling came from recognising that this could become a larger issue in the future. The team looked at practices at J-PARC, where a recovery process is already in place, and saw an opportunity to adapt a similar approach at ISIS. What started as a concern about cost and availability quickly developed into a practical solution that could also contribute to more sustainable lab operations.
How does the process work?
The process itself is relatively straightforward but carefully controlled. Contaminated D₂O is recovered using a rotary evaporator, where the liquid is evaporated and then condensed to produce purified deuterated water. After this, the recovered material is thoroughly analysed to ensure it is suitable for reuse. One of the main techniques used is Nuclear Magnetic Resonance spectroscopy (NMR), which allows scientists to see what compounds are present by producing a spectrum of the sample. This is particularly useful for identifying small organic impurities. However, because no single method can detect everything, additional tests such as conductivity measurements and ion chromatography are also used to check for any remaining contaminants. A fluorescence-based method, known as Lanthlux, is used to determine the concentration of D₂O, typically confirming levels ranging from as low as around 5% to as high as 95%. Together, these methods ensure that the recovered material is well understood and safe to reuse.
Making it practical
In terms of practicality, the process fits easily into normal lab routines. Recycling a one-litre bottle usually takes around one to two hours, but it does not require constant attention. Much like other evaporation techniques commonly used in laboratories, samples can be set up and left to run while researchers focus on other tasks, making it an efficient addition to existing workflows.
Working with users
A key part of making the system work has been involving users. When returning D₂O, users are encouraged to provide as much information as possible about what the sample contains, which helps the team decide how it can be reused. Once analysed, the recovered D₂O is sorted based on its purity. The highest quality material is sent back to beamlines for experimental use, while D₂O with some level of contamination is reused in biolabs and deuteration labs for synthesis work. This flexible approach means that very little goes to waste.
At the beginning, there was some hesitation from users about relying on recycled material, which is understandable in a research environment where accuracy is critical. Building trust therefore became an important part of the process.
Impact and future plans
By carefully tracking every sample, sharing results, and working closely with instrument scientists to test the recycled D₂O, the team was able to demonstrate that it met the required standards. Practical steps were also introduced to make participation easier, such as placing labelled trolleys in key locations like, Inter, the West Prep Lab, and the biolabs, Deuteration facility where users can leave their samples, along with relevant information. A dedicated email contact (D2O@stfc.ac.uk) has also been set up for queries, and there are plans to expand collection points further so that the system becomes even more accessible.
“So far, the results have been very encouraging, with around 130 litres of D₂O successfully recycled” says June. This not only represents a significant cost saving but also reduces the environmental impact associated with producing new deuterated water. Looking ahead, the team hopes to document their work in a technical report so that other facilities can learn from their experience. By sharing what they have developed, they aim to support a wider shift towards more sustainable and efficient use of resources across the neutron science community.
