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Today, we can say that there are several challenges to make liquid hydrogen a source of green energy, and an effective alternative to fossil fuels. One of the great challenges is its abundance, as there is little liquid hydrogen on earth, in pure form, as a large part is contained in water.
However, something new appeared in the scientific world. A team of scientists has managed to produce liquid hydrogen from air, producing the substance through renewable energy. The study was published in an article on hydrogen in Nature Communications Magazine. Unlike other raw materials such as oil and natural gas, the combustion of hydrogen does not produce carbon, the gas that is responsible for the advance of the greenhouse effect, producing only water. Thus, hydrogen is an excellent alternative as a green fuel.
However, obtaining liquid hydrogen is still a big challenge. This is because it is part of the composition of water (H2O) and compounds such as oil and natural gas. Thus, it is necessary to obtain a chemical process to remove that element from the compounds, which costs energy and a high value for the project creators. On the other hand, we also have a problem, since obtaining hydrogen from fossil fuels also generates carbon dioxide, therefore, these sources remain ineffective in the production of clean energy, being a pillar for the advancement of the greenhouse effect on the planet.
Liquid hydrogen is a great option to fight the greenhouse effect
To produce liquid hydrogen from water, a process known as electrolysis is used. Basically, electric current is used to split water molecules into hydrogen and oxygen. This process was the cornerstone of the project led by Gang Kevin Li, who works in the Department of Chemical Engineering at Melbourne University, in Australia. However, to differentiate the project, instead of using liquid water, the scientists were able to collect moisture from the air to produce liquid hydrogen. For this, they used a kind of sponge equipped with substances capable of absorbing moisture from the air, such as sulfuric acid, for example.
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Then, with the help of electrical energy coming from renewable sources, such as wind or solar energy, they used electrolysis to split water molecules, obtaining the production of gaseous hydrogen. In an article published in New Scientist magazine, Kevin Gang Li, project coordinator, said that this is the first technology capable of producing highly pure hydrogen directly from the air, and it is possible to carry out the process anywhere on earth, as long as there is enough energy. The scientist stated that the process occurs even in atmospheric conditions of 4% humidity, equivalent to a very low concentration of water in the air.
Liquid hydrogen can be produced anywhere on Earth
The new process allows the production of liquid hydrogen in regions with great scarcity of liquid water, such as in desert environments, but which have an endless source of renewable energy, solar. The apparatus assembled by the scientist's team uses painéis solares, which are capable of operating for 12 consecutive days. In this way, the team estimates that it is possible to obtain 745 liters of liquid hydrogen per square meter in just 24 hours, from the material that absorbs moisture from the air. Basically, the liquid hydrogen It needs little energy to ignite. Thus, it is worth mentioning that it has the capacity to become flammable according to the tendency to change its physical state, especially when, during the change, the gas mixes with the air.
