In 2016, experts writing in Nature listed seven breakthroughs in how we process chemicals that could change the world for the better. We believe we've just ticked one of those off the list.
Credit: Shutterstock In our study published in Materials Today, we found a highly efficient and entirely novel way to separate, purify, store and transport huge amounts of gas safely, with no waste. Why is this breakthrough so important? We believe it will help overcome the key challenge of hydrogen storage by allowing us to safely store and transport huge quantities of green hydrogen as a solid at a fraction of the energy cost. This will allow us to accelerate uptake of green hydrogen, as well as allow oil refineries to use much, much less energy, and make processing many other gases easier. Right now, breaking crude oil into petrol and other gases in oil refineries relies on the hugely energy intensive process of cryogenic distillation. This accounts for up to 15% of the world's energy use. By contrast, we estimate our new method would cut this energy use by up to 90%. This method offers the world a solid storage method for gases with a far higher capacity than any previous material. The absorbed gases can be recovered via a simple heating process leaving both the gases and the powder unchanged, allowing for immediate use or re-use. What did we find? The breakthrough is so significant—and such a departure from accepted wisdom on gas separation and storage—that our research team repeated our experiment 20 to 30 times before we could truly believe it ourselves. So how does it work? Our new approach uses a new method called "ball milling" to store gas in a special nanomaterial at room temperature. This method relies on mechanochemical reactions, meaning machinery is used to produce unusual reactions. The special ingredient in the process is boron nitride powder, which is great for absorbing substances because it is so small yet has a large amount of surface area for absorption. To make this work, boron nitride powder is placed into a ball mill—a grinder containing small stainless-steel balls in a chamber—along with the gases that need to be separated. As…