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Define Liquid Oxygen

Earth's atmosphere contains several gasses, with oxygen being the second largest amount of gas at nearly 21 percent by volume. Oxygen not only supports life, it finds its way into medical treatments, industrial uses like space sciences. Most of these additional uses require a more pure form of oxygen that the atmosphere provides. Gas manufacturing plants produce this pure form of oxygen in a form called Liquid Oxygen, or LOX for short.

Liquie Oxygen Physical Properties
- Liquid Oxygen has the same molecular formula -- O2 -- as oxygen in the atmosphere. It has a freezing point of negative 361.9 degrees Fahrenheit, or negative 183 Celsius, and a boiling point of negative 181.8 degrees Fahrenheit, or negative 218.8 Celsius. In its cryogenic liquid form, LOX appears pale blue in color, uses less storage space in its condensed state which costs less to store and returns to a gas state at temperatures higher than negative 118 degrees Fahrenheit, or 83.6 Celsius.
Liquid Oxygen Production
- Gas manufacturing plants generally use one of three methods for producing oxygen production for commercial use. The first method involves running electric current through water to separate the two gases, hydrogen and oxygen, and collect them in separate storage containers. The second produces a chemical reaction that unbinds oxygen from a chemical compound. The third, and most common, entails separating oxygen from the other gasses in the atmosphere putting it through a cryogenic distillation process, which freezes the gas until it converts to a liquid state.
Storing Liquid Oxygen
- Cryogenic LOX storage consists of bulk storage tanks, holding 40 to 100 lbs. of LOX, and portable, refillable storage containers, carrying between 6 and 11 lbs. of LOX. The bulk storage tank and portable container constructions consists of internal and external reservoirs with a vacuum layer sandwiched between, much like a thermos bottle. This tank setup provides insulation for the cryogenic liquid, which protects the LOX from the warmer temperatures outside the tanks, and prevents it from returning to its gas state prematurely. These insulated tanks, called dewars, maintain the LOX in its liquid state in a lower chamber, and in its thawed, gas state in an upper chamber. A flow control valve, when opened, dispenses O2 to patients in a home setting.
Liquid Oxygen Uses
- LOX use benefits patients with chronic diseases in their home treatment plans. Hospitals use use LOX for the treatment of respiratory and cardiac failure, resuscitation of critically ill patients, O2 therapy in neonatal units, as a carrier gas for anesthesia drugs and for post-operative patient care. Industrial uses include space rockets for breathable air, as a liquid propellant for rockets and ICBM, and as a liquid oxygen binary explosive, an explosive that requires mixing with another agent to become explosive.

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