Imagine pulling up to a refueling station and filling your vehicle’s tank with liquid hydrogen, as safe and convenient to handle as gasoline or diesel, without the need for high-pressure tanks or cryogenic storage. This vision of a sustainable future could become a reality if a Calgary, Canada–based company, Ayrton Energy, can scale up its innovative method of hydrogen storage and distribution. Ayrton’s technology could make hydrogen a viable, one-to-one replacement for fossil fuels in existing infrastructure like pipelines, fuel tankers, rail cars, and trucks.
The company’s approach is to use liquid organic hydrogen carriers (LOHCs) to make it easier to transport and store hydrogen. The method chemically bonds hydrogen to carrier molecules, which absorb hydrogen molecules and make them more stable—kind of like hydrogenating cooking oil to produce margarine.
A researcher pours a sample of Ayrton’s LOHC fluid into a vial.Ayrton Energy
The approach would allow liquid hydrogen to be transported and stored in ambient conditions, rather than in the high-pressure, cryogenic tanks (to hold it at temperatures below -252 ºC) currently required for keeping hydrogen in liquid form. It would also be a big improvement ongaseous hydrogen, which is highly volatile and difficult to keep contained.
Founded in 2021, Ayrton is one of several companies across the globe developing LOHCs, including Japan’s Chiyoda and Mitsubishi, Germany’s Covalion, and China’s Hynertech. But toxicity, energy density, and input energy issues have limited LOHCs as contenders for making liquid hydrogen feasible. Ayrton says its formulation eliminates these trade-offs.
Safe, Efficient Hydrogen Fuel for Vehicles
Conventional LOHC technologies used by most of the aforementioned companies rely on substances such as toluene, which forms methylcyclohexane when hydrogenated. These carriers pose safety risks due to their flammability and volatility. Hydrogenious LOHC Technologies in Erlanger, Germany and other hydrogen fuel companies have shifted toward dibenzyltoluene, a more stable carrier that holds more hydrogen per unit volume than methylcyclohexane, though it requires higher temperatures (and thus more energy) to bind and release the hydrogen. Dibenzyltoluene hydrogenation occurs at between 3 and 10 megapascals (30 and 100 bar) and 200–300 ºC, compared with 10 MPa (100 bar), and just under 200 ºC for methylcyclohexane.
Ayrton’s proprietary oil-based hydrogen carrier not only captures and releases hydrogen with less input energy than is required for other LOHCs, but also stores more hydrogen than methylcyclohexane can—55 kilograms per cubic meter compared with methylcyclohexane’s 50 kg/m³. Dibenzyltoluene holds more hydrogen per unit volume (up to 65 kg/m³), but Ayrton’s approach to infusing the carrier with hydrogen atoms promises to cost less. Hydrogenation or dehydrogenation with Ayrton’s carrier fluid occurs at 0.1 megapascal (1 bar) and about 100 ºC,…
Read full article: Hydrogen Storage Made Easier With New Carrier Fluid
The post “Hydrogen Storage Made Easier With New Carrier Fluid” by Willie D. Jones was published on 10/31/2024 by spectrum.ieee.org