Barium peroxide

Barium peroxide is an inorganic compound with the formula. This white solid is one of the most common inorganic peroxides, and it was the first peroxide compound discovered. Being an oxidizer and giving a vivid green colour upon ignition, it finds some use in fireworks; historically, it was also used as a precursor for hydrogen peroxide.

Structure

Barium peroxide consists of barium cations and peroxide anions. The solid is isomorphous to calcium carbide,.

Preparation and use

Barium peroxide arises by the reversible reaction of with barium oxide. The peroxide forms around and oxygen is released above.
This reaction is the basis for the now-obsolete Brin process for separating oxygen from the atmosphere. Other oxides, e.g. Sodium oxide| and SrO, behave similarly.
In another obsolete application, barium peroxide was once used to produce hydrogen peroxide via its reaction with sulfuric acid:
The insoluble barium sulfate is filtered from the mixture.