How are most large quantities of medical oxygen produced?

Most large quantities of medical oxygen are produced through fractional distillation of atmospheric air. This method leverages the different boiling points of the components in air, primarily oxygen and nitrogen. By cooling air to extremely low temperatures, it condenses into a liquid, where the various gases can be separated based on their boiling points as the mixture is slowly warmed.

Oxygen, which has a boiling point of about -183 degrees Celsius, evaporates and can be collected while nitrogen, with a boiling point of -196 degrees Celsius, remains liquid longer. This process is efficient for producing high-purity oxygen required for medical uses and can be scaled to meet large demands. Additionally, fractional distillation yields a consistent and reliable product, essential for medical standards.

Other methods, such as electrolysis of water, produce oxygen but typically on a smaller scale and are not practical for large-scale medical oxygen production. Heat treatment of water does not efficiently produce oxygen, and compression of oxygen gas refers to storing already produced oxygen rather than its production. Hence, fractional distillation is the preferred and standard method in the medical field for generating significant quantities of oxygen.