Hydrogen is used to manufacture the important chemical compounds ammonia and methanol, according to the Essential Chemical Industry. It is also used in such oil refinery processes as reforming, in which sulfur compounds are removed from petroleum to improve the petroleum's quality.
Hydrogen is the most abundant element in the universe, states the Royal Society of Chemistry. On Earth, the largest quantities are found in water. Small amounts are present in the atmosphere.
The Essential Chemical Industry explains that hydrogen is a valuable manufacturing starting material. It is a fundamental building block used to produce ammonia for fertilizer, as well as methanol, a chemical compound used in manufacturing numerous polymers. Moreover, hydrogen is used in making cyclohexane, an intermediate in the production of plastics and pharmaceuticals, says the RSC. Large quantities of hydrogen are also used in hydrogenating oils to produce fats. Other uses of this element include welding and reducing metallic ores.
Liquid hydrogen has a melting point above absolute zero, making it essential to cryogenics and superconductivity studies. Hydrogen holds a significant potential as a clean fuel generated from water that returns to water when oxidized. Hydrogen-powered fuel cells are increasingly being considered as a viable, pollution-free energy source.