Hydrogen has proven to be one of the most efficient fuels available. The little emissions it gives out and its little negative effect on the environment have made it a serious competitor against fossil fuels.
Hydrogen is not extracted from deep inside the earth like fossil fuels, so how is it made? Several processes are used to extract hydrogen from other compounds such as water and methane. Hydrogen can also be produced from biomass and fossil fuels.
Hydrogen’s efficiency and impact on the environment depend almost entirely on the processes used to extract it. Some of the methods used to produce hydrogen are:
- During this process, an electric current is used to split water into hydrogen and oxygen molecules. If the electric current used in the process is produced by renewable energy sources such as wind or solar, the hydrogen that is produced is also considered renewable.
- This is the process by which hydrogen gas is extracted from natural gas. When natural gas is reacted with high-temperature steam, synthesis gas is created. This is a mixture of hydrogen, carbon monoxide, and carbon dioxide. The carbon monoxide produced is reacted with water to produce some more hydrogen. Gasification accounts for most of the hydrogen produced. It is the cheapest method of hydrogen production.
- Hydrogen can be produced by fermentation. During fermentation, biomass is converted into sugar-rich feedstocks that, when fermented, produce hydrogen.
- Renewable liquids are reforming. During this process, renewable liquid fuels like ethanol are reacted with high-temperature steam to form hydrogen.
Although there are methods of producing hydrogen that have already been proven to work, there has been an interest in creating cheaper ways to produce hydrogen. Experts are researching more ways of making hydrogen. Several methods of hydrogen production are still in development. Some of them are:
- High-temperature water splitting. In this method, high temperatures have to be generated. These temperatures are achieved through solar concentrators or nuclear reactors. The high temperatures are used to drive the chemical reactions that split hydrogen from water.
- Photoelectrochemical water splitting. During this process, hydrogen is split from water using photoelectrochemical systems. These systems use special semiconductors coupled with energy from the sun to get this done.
- Photobiological water splitting. In this process, microbes are used to consume water in sunlight, producing hydrogen as waste.
One of the biggest problems in hydrogen production has always been how to pry the hydrogen apart from other molecules. Some scientists have found a way of doing this more efficiently. They produce hydrogen fuel using light from a mercury-xenon lamp, a solution of methanol and water, and rust. The rust acts as a catalyst. In this method, by using rust, the hydrogen formed cannot fuse with oxygen again, thus making the separation of elements easier and reducing the risk of an explosion. The rust is used instead of a titanium dioxide catalyst, thus making the process cheaper. By substituting titanium dioxide with iron oxide (rust), the process is made much more efficient.
Article by Salah M. Al for Epistle News.