Element Six (E6), a world leader in synthetic diamond innovation and part of the De Beers Group, reports that a new piece of academic research conducted by University of Surrey has validated its boron doped diamond electrode material as a successful solution to break down the carbon-fluorine bond found in short chain PFAS compounds, offering a scalable treatment option for PFAS destruction.
A diamond solution to tackle PFAS
Synthetic free standing boron doped diamond (BDD), packaged into Element Six’s Diamox™, is a cost-effective and highly efficient solution designed to breakdown dissolved pollutants in waste streams. Diamox™ had already been successful in treating extremely contaminated industrial effluents, including spent caustic, pharmaceutical and textile dye wastewaters – all challenges that cannot be tackled by conventional water treatment processes.
Building up on BDD’s existing applications, University of Surrey, School of Chemistry and Chemical Engineering, has recently completed a series of tests using Element Six’s diamond electrodes to treat a solution containing two types of short chain PFAS compounds: Perfluoroalkyl Butanoic Acid (PFBA) and Perfluoroalkyl Butane Sulfonic Acid (PFBS).
Dr Madeleine Bussemaker, who led the University experimental work, commented: “Shorter chain PFAS, like PFBA and PFBS, are often harder to break down and can even be produced when PFAS mixtures are treated with conventional degradation technologies. This is why we look at new, emerging technologies like electrolysis and high-frequency ultrasound to treat PFAS. Using BDD, we saw that fluoride release could be as high as >90% of initial fluorine in the PFAS. This was a really exciting result to see in such a preliminary study. Further work is ongoing to translate these results to optimise conditions and applicability of BDD to a range of PFAS types.”
Dr Tim Mollart, Principal Engineer at Element Six, said: “Shorter chain PFAS compounds are shown to accumulate in the environment and, given the ecological risks they pose, the world is now searching for an efficient solution to destroy them. Based on this premise, it is encouraging to see that free-standing BDD electrode water treatment technology is successfully breaking apart the carbon fluorine bonds in the shortest chain PFAS compounds. In this work Element Six’s electrochemical technology has been shown to deliver extremely intense PFAS destruction conditions at the surface of the diamond, in an otherwise low temperature and low-pressure process. Diamox™ has a proven 10-year track record performance in pharmaceutical, textile industries and refinery wastewaters.”
University of Surrey and Element Six will publish detailed findings from the study in the near future which fit into the multi-stage remediation and destruction PFAS treatment chain. With groups already approaching pilot scale with PFAS destruction technology incorporating Diamox™, Element Six continues to support research work that underpins the efforts to develop PFAS disposal solutions that meet the rigorous standards appropriate for these hazardous waste streams.
Why is the research relevant today?
On the 14th March 2023, the United States Environmental Protection Agency (EPA) announced a proposal for long-anticipated national drinking water standards for six PFAS chemicals: PFOA, PFOS, PFNA, PFHxS, PFBS, and GenX. The new EPA proposal - the National Primary Drinking Water Regulation - sets limits of four parts per trillion for the two most common and widespread PFAS chemicals: PFOA and PFOS. The remaining four will have a combined, calculated limit weighted by their respective health risks.
This move by the EPA is, thus far, one of the most substantial acts by the US Federal Government to regulate PFAS. If finalised, after a public comment period, the proposed regulation will require public water companies to actively monitor PFAS contents in their water, notifying the public and addressing their processes to reduce PFAS contamination, if such limits are exceeded. In Europe and the UK, PFAS have been found to be ubiquitous in rivers and lakes, detected in soils, plants and animals. Significant ground water contamination has been detected in areas around airports, manufacturing facilities and other sites, leading to increasing pressure on regulators to follow the US lead and reduce permitted PFAS levels in drinking water.
What are PFAS?
PFAS are a large range of synthetic fluorinated organic compounds that have been produced and widely used in industrial applications and consumer products since the 1950s. The substances are also known as ‘forever chemicals’ because they are extremely stable and do not naturally or easily break down, leading to an inevitable build-up over time in the environment and in animals. In humans, PFAS are linked to increased cholesterol levels, incidences of cancer, liver and kidney disease, as well as other serious health problems, such as slower foetal development and lower levels of fertility.