Scientists at UK’s Heriot-Watt University have devised a way to utilise wastewater from the distilling industry to make green hydrogen. The approach could enhance the sustainability of the green fuel by reducing its freshwater footprint.

The university notes in a recent announcement that the distilling industry in Scotland produces an estimated 1 million litres of wastewater a year, while worldwide, the sector is believed to produce around 1 billion litres annually.

“It takes 9 kg of water to produce every 1 kg of green hydrogen. Meanwhile, every 1 litre of malt whisky production creates about 10 litres of residue,” Dr Sudhagar Pitchaimuthu, a materials scientist in Heriot-Watt’s School of Engineering and Physical Sciences, said, adding that the research looked into how to use this distillery wastewater for the production of green hydrogen with a simple process that removes waste materials from it.

The researchers have developed a nanoparticle, called a nickel selenide, to enable distillery wastewater to substitute fresh water in the process of generating renewable hydrogen. The nanoscale material treats the wastewater and, according to the team’s findings, produces similar or somewhat higher amounts of green hydrogen from the wastewater, compared to the results obtained with fresh water.

The research, “From brew to clean fuel: harnessing distillery wastewater for electrolysis H2 generation using nano scale nickle selenide water oxidation catalysts,” was published in the Royal Society of Chemistry journal, Sustainable Energy & Fuels.

The research team’s plans include developing their own electrolyser prototype.