Lithium peroxide

Lithium peroxide

Lithium peroxide (Li2O2) is an inorganic compound and a member of the peroxide family. It is mainly used as a oxygen source and in other applications where its ability to release oxygen is valued, such as in spacecraft life support systems. Lithium peroxide is a white or off-white solid at room temperature and is soluble in water, where it slowly decomposes to release oxygen and lithium hydroxide.

Properties

Lithium peroxide has a molecular weight of 45.88 g/mol and a density of 2.4 g/cm^3. It decomposes at temperatures above 195°C, releasing oxygen and leaving behind lithium oxide (Li2O). Its solubility in water leads to a slow reaction, forming lithium hydroxide (LiOH) and releasing oxygen gas (O2).

Synthesis

Lithium peroxide can be synthesized by reacting lithium hydroxide with hydrogen peroxide (H2O2), a process that yields lithium peroxide and water. This reaction is exothermic and must be carefully controlled to prevent rapid decomposition of the product.

Applications

The primary application of lithium peroxide is in environmental control and life support systems (ECLSS) in spacecraft. It is used to absorb carbon dioxide from the air and release oxygen, thus supporting life in closed environments. This property is also explored for potential use in submarines and underwater habitats.

Safety

Lithium peroxide is a strong oxidizer and can cause fires if it comes into contact with organic materials or certain metals. It should be handled with care, and appropriate safety measures should be taken, including the use of protective equipment and storage in a cool, dry place.

Environmental Impact

While lithium peroxide can be beneficial in closed-loop life support systems, its production and disposal must be managed carefully to minimize environmental impact. The use of lithium, a limited resource, also raises concerns about sustainability and environmental footprint.