Neon is a rare gas that is found in natural air. However, its content is too small, accounting for only 18 parts per million of the total amount of air.
The proportion of various substances in normal air.
Wherein: including noble gases, argon, argon, kryptonkrkr, xenon xe, radon rn is 0939% argon, although the proportion of neon is in second place, but it is conceivably very little.
Since neon is extracted from the air, why is it said that it is a by-product of the iron and steel enterprise?As we all know, steel production requires a lot of oxygen. With such a large quantity, all the procurement costs are not economical. As a result, large steel companies often build their own air fractionation plants. In addition to obtaining the oxygen required for production, gases such as nitrogen, argon, neon, helium, etc., can also be separated from the air. This is called a by-product. Of course, due to technical reasons, ordinary steel companies may not be able to further process and separate these noble gases.
After discussing the content, let's talk about its features. Separation is more difficult if there is only a low content and a low critical boiling point (liquid-air separation is mainly used to extract gases, i.e. liquefaction first, followed by heating, evaporation, and separation). The boiling point of neon gas (-248.)6 degrees Celsius) close to hydrogen (boiling point -252.).77 degrees Celsius), above the boiling point of helium (-268.).90 degrees Celsius). Neon and helium must be extracted using the deep cooling method. Neon usually requires liquid hydrogen or liquid helium to liquefy.
As far as the current technical methods are concerned, the process steps of high-purity neon gas: concentration, hydrogen removal, nitrogen removal, low-temperature adsorption, neon gas separation, etc. The most difficult step is neon helium separation, which is why all research into the production process of high-purity neon has focused on how to remove trace amounts of helium from neon.