Fractional distillation of air

On the industrial scale oxygen is obtained by the fractional distillation of air. A common laboratory method for the preparation of oxygen is by the decomposition of hydrogen peroxide. H Oj, a reaction catalysed by manganese(IV) oxide ... 

Industrially, it is manufactured either by fractional distillation of air, or by electrolysis of sodium hydroxide and it is distributed as a non-liquefied gas in pressurized black cylinders at ca 2200 psig at 21°C. Since it is non-corrosive no special materials of construction are required. 

Nitrogen, oxygen and argon are produced by fractional distillation of air. Liquid nitrogen (LN) is a quite cheap and safe source of cold and finds applications such as ... 

The potential for the condensation and fractional distillation of air on the outside of equipment containing cryogenic liquids with boiling points less than that of 02 must be considered. For example, because N2 boils at a lower temperature than 02 (-196 versus -183°C), air can condense on the outside of liquid N2-bearing piping. The liquid that drops off of the piping will be enriched in 02 and can pose an enhanced fire or explosion risk in the vicinity of the equipment. 

Fractional distillation of air The process used to extract individual gases from the air. Air is a major raw material. The mixture of gases is separated by first liquefying the mixture at low temperature and high pressure. The temperature is then allowed to rise and the gases collected as they boil off. The gases so produced have many and varied uses. 

Neon can be obtained from air by fractional distillation. The first step in fractional distillation of air is to change a container of air to a liquid. The liquid air is then allowed to warm up. As the air warms, each element in air changes from a liquid back to a gas at a different temperature. The portion of air that changes back to a gas at —410.66°F (—245.92°C) is neon. 

Molecular nitrogen is obtained by fractional distillation of air (the boiling points of liquid nitrogen and liquid oxygen are -196°C and -183°C, respectively). In the laboratory, very pure nitrogen gas can be prepared by the thermal decomposition of ammonium nitrite ... 

In order to obtain the desired mixture of 3 parts of hydrogen and I part of nitrogen, approximately two volumes of water gas are mixed with one volume of producer gas. This mixture is deficient in nitrogen, which deficiency is made up by the addition of free nitrogen, procurable through the liquefaction and fractional distillation of air, in order to keep accurate control of the composition of the mixture. 

Dioxygen is obtained industrially by the liquefaction and fractional distillation of air, and is stored and transported as a liquid. Convenient laboratory preparations of O2 are the... 

Atmospheric nitrogen is the ultimate source of all commonly used nitrogen compounds. The liquefaction and fractional distillation of air provide the N2 fi om which the important compounds are synthesized. Ammonia is made from N2 (the Haber process) by reaction with H2 from natural gas, nitric acid is made from ammonia in several steps, ammonium nitrate is made from the reaction of nitric acid with ammonia, urea is made from ammonia and carbon dioxide, and ammonium sulfate is prepared by the reaction of ammonia and sulfuric acid. 

Nearly all oxygen is prepared by fractional distillation of air, and most of the huge amoimt produced is used for steehnaking and welding purposes. Oxygen finds considerable application in medicine, and a significant quantity of liquid oxygen is employed as the oxidant in rocket fuels. 

Distillation and adsorption techniques are those which first come to mind for separation of the rare gases. The pure rare gases have of course been successfully produced commercially by the fractional distillation of air, with the exceptions of helium which is extracted from certain Texas natural gases and radon which is obtained as a member of the 4n+2 natural radioactive decay... 

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