Hydrogen is extremely useful as a fuel. It can be used in industry as well as in hydrogen-powered vehicle. Howerver, although hydrogen is the most abundant element on Earth, it is difficult to capture and purify. The process requires a lot of energy and thus is not very green. But now an international team of scientists led by the Newcastle University, UK, developed the first thermodynamically-reversible chemical reactor ever.
This new kind of hydrogen generator relies on transferring oxygen between reactant streams via a solid state oxygen reservoir. That reservoir remains close to equilibrium with the reacting gas streams, which created the condition of chemical memory in the reaction. This may sound like a complex device and it really is, but the result is a constant production stream of hydrogen, which saves energy and does not require a costly separation of the final products. Previously these results were achieved through a mixing reaction, which was energy-hungry and time-consuming. Scientists say that this new method produces a pure stream of green hydrogen.
Scientists say that this reactor is pretty close to being perfect, because it produces pure, separated products. Hydrogen Memory Reactor could revolutionize hydrogen production, which will infuence the entire energy sector. Hydrogen is a cleanenergy source, typically obtained from splitting water molecules. Current methods of chemical, mechanical or electrical separation are thermodynamically irreversible. This means that produced hydrogen then has to be separated from other products, which is a long and energy-inefficient process. The new reactor is approaching thermodynamically-reversible operation, which would yield green hydrogen in a shorter and less energy intensive process. Scientists describe it as a one step unit.
Reaction between water and carbon monoxide generates hydrogen and carbon dioxide. Carbon can be easily carried onto the final product contaminating it and creating a need for a purifying process. However, this new Hydrogen Memory Reactor prevents carbon from being carried into the hydrogen produce stream as carbon monoxide or carbon dioxide – carbon dioxide and hydrogen are produced at either end of the reactor as pure products. Ian Metcalfe, lead author of the study, said: “Whereas conventional hydrogen production requires two reactors and a separation, our reactor accomplishes all the steps in one unit. And while we demonstrate the concept with hydrogen, the memory reactor concept may also be applied to other processes”.
Green hydrogen is a huge accomplishment, which could encourage all kinds of development, including a steady supply of hydrogen for fuel cell vehicles. Clean hydrogen is a very important goal, which could transform energy sector.
Source: Newcastle University