What Is Magnesium Hydride?
Magnesium hydride, represented by the chemical formula MgH2, is a crystalline solid that ignites upon contact with water or moist air. It can absorb up to 7.6% hydrogen by weight, making it an attractive candidate for hydrogen storage due to its high absorption capacity and the abundance of magnesium on Earth. Hydrogen is released through the hydrolysis of magnesium hydride.
Uses of Magnesium Hydride
1. Hydrogen Storage Materials
At room temperature and pressure, magnesium hydride is stable and capable of storing large amounts of hydrogen, positioning it as a promising hydrogen storage material. Despite challenges related to its release temperature and rate, its abundant availability and established production process present low industrialization barriers.
2. Fuel Cell Vehicle (FCV)
Fuel cell vehicles, which emit only water as a byproduct, utilize magnesium hydride as a hydrogen carrier. Produced under high temperature and pressure, it can be stored in solid or paste form in cartridges, offering a lightweight alternative to traditional storage materials.
3. Civilian Applications
Beyond industrial uses, magnesium hydride finds applications in consumer products like hydrogenated water, hydrogen baths, bath salts, and beauty treatments.
Properties of Magnesium Hydride
With a molecular weight of 26.32 and a density of 1.45, magnesium hydride has no defined flash or boiling points and decomposes into metal oxides and hydrogen upon decomposition. It requires storage away from high temperatures, sunlight, and moisture.
Other Information on Magnesium Hydride
1. Safety
As a water-reactive flammable chemical, magnesium hydride poses risks of spontaneous ignition upon water contact and is an irritant to the skin and eyes. Disposal must adhere to regional and local regulations.
2. First Aid Measures
Eye and skin contacts require immediate rinsing and medical consultation if irritation persists. Ingestion necessitates mouth rinsing and medical intervention without inducing vomiting unless directed.
3. Handling Methods
Local exhaust ventilation and inert gas work environments are recommended to prevent fire risks from water or moisture contact. Personal protective equipment is essential for safe handling.
4. Storage
Magnesium hydride should be stored in a cool, well-ventilated place in containers purged with inert gas and shielded from light to avoid water contact and minimize hazard risks.