Argon is produced industrially as a byproduct in the production of liquid oxygen and liquid nitrogen by the fractional distillation of liquid air in a cryogenic air separation unit; a process that separates liquid nitrogen, which boils at 77.3 K, (-320oF, -196oC), from Argon, which boils at 87.302 K, (-185.848 °C,-302.526 °F), and liquid Oxygen, which boils at 90.2 K, (-297oF, -183oC). The name “Argon” is derived from a Greek word meaning “lazy” or “inactive”, as a reference to the fact that the element undergoes almost no chemical reactions.
Argon occurs naturally in air. Argon is the third most common gas in the Earth’s atmosphere, at 0.93% (9,300 ppm), making it approximately 23.7 times as abundant as the next most common atmospheric gas, Carbon Dioxide (390 ppm), and more than 500 times as abundant as the next most common noble gas, Neon (18 ppm). Argon is the most prevalent of the noble gases in Earth’s crust, with the element composing 0.00015% of this crust. The Earth’s crust and seawater contain 1.2 ppm and 0.45 ppm of Argon, respectively.
Argon has approximately the same solubility in water as oxygen, and is 2.5 times more soluble in water than nitrogen. Argon is colorless, odorless, nonflammable and nontoxic as a solid, liquid, and gas. Argon is chemically inert under most conditions and forms no confirmed stable compounds at room temperature.
Although argon is a noble gas, it has been found to have the capability of forming some compounds.
Although argon is non-toxic, it is 38% denser than air and is therefore considered a dangerous asphyxiant in closed areas. Argon’s relatively high density (1.784 g/L in gaseous state and 1.3954 g/cm3 in liquid state) causes it to remain close to the ground during gassing. It is also difficult to detect because it is colorless, odorless, and tasteless.
Many incidents published worldwide highlight the dangers of argon tank leakage in confined spaces, and emphasizes the need for proper use, storage and handling.
IS 5760: 1998
The cylinders are available in 7.5 m3 capacity, 150 kg/cm2 pressure, 11m3 at 200 kg/cm2 and 12 m3 at 200 kg/cm2. Portable cryogenic containers
Pure Argon and Argon mixed with various other gases, is used as a shield gas in “TIG”(Tungsten Inert Gas or gas tungsten arc welding) and “MIG”(Metal Inert Gas or gas metal arc welding or wire feed welding ) welding processes of mild & low alloy steels, stainless steel, Al, Cu, Mg, Ni and alloys.
Plasma-arc cutting and plasma-arc welding employ plasma gas(Argon and Hydrogen) to provide a very high temperature when used with a special torch.
As a shield gas in casting and stirring of ladles(type of spoon)
Reduces Chromium losses and the desired carbon content is achieved at a lower temperature
In Aluminium manufacture to aid degasification and remove dissolved hydrogen and particulates from molten Aluminium
In the manufacture of Zirconium
As an inert gas in the manufacture of Titanium to avoid oxidation and reaction with Nitrogen(Titanium is the only metal that will burn in a 100% Nitrogen atmosphere) and other reactive elements and primarily ice coring(core sample from the accumulation of snow and ice)
Atomizing critical ferrous and non-ferrous alloys by argon to produce powder metal.
Controlled furnace atmosphere in sintering (welding together of small particles of metal by applying heat at temperature below melting point) powder metal items.
At high pressures, it is used for hot isostatic pressing (enables to produce various types of materials from powder compacts by reducing the porosity of powder mixture) of sintered or encapsulated powder metal.
Ultra high purity argon is used as a protective gas in the manufacturing process of optical fiber (It is a light pipe which transmits light between the two ends of the fiber).
Argon is used with methane as a filler gas, and as a high purity inert shield gas in the manufacture of “Silicon” and “Germanium” crystals.
Manufacture of integrated circuit chips involve high purity argon application in Silicon crystal growing.
Oxide removal (etching) by dry-plasma process and doping (adding of impurities) of wafers for desired chemical composition.
Food and Beverages- Argon is used in wine making to displace oxygen in barrels and thus prevent the formation of vinegar.
It can be used in controlled atmosphere in place of Nitrogen. Its solubility (2 times that of N2) and certain molecular characteristics give it special properties for use with vegetables.
In the pharmaceutical industry to top off bottles of intravenous (into a vein) drug preparation (eg. Intravenous “paracetamol”) for prolonging the drug’s shelf-life.
Argon is used for filling of double glazing (process in which a window is formed by two panes of glass with a space between them) enclosures for high performance thermal isolation.
Ultra high purity Ar as purge and shield gas is used for fast and accurate analysis of metal samples using “Spectrometers”.
Pure Ar or in mixtures is used for industrial and hospital analyses and “quality control”.
Used as plasma gas in “inductive coupled plasma emission spectrometry” (ICP), blanket gas in “graphite furnace atomic absorption spectrometry”(GFAAS)
Used as a carrier gas in “gas chromatography” for various detector.
Argon/Methane mixture is used in “Geiger-Muller” counter(particle detector) and in the X-Ray.
Fluorescence (XRF)” detector as the quenching gas (cooling gas).
Argon is a shield gas for arc welding, plasma cutting and root shielding. It protects welds against oxidation and reduces fume emissions during welding.
Argon in pressurized packs is used to inflate (swell with gas) car airbags
Liquid Argon is used in “Cryo Surgery” procedures such as “Cryoablation” (technique used to destroy cancer cells)
It is used to treat abnormal electrical activity (arrhythmia) in the heart).
Standard and ultra high purity Ar, Ar/N2, Ar/Ne, Ar/Kr, Ar/He/H2, Ar/Xe mixtures of various proportions used for filling bulbs, fluorescent tubes, miner’s lamp, glow lamp starters, flash gun lamp etc. for energy efficient high intensity lighting.
Ar as inert gas with O2 to control carbon in secondary steel making and high grade alloys, flat carbon steel and high quality long products and to reduce chromium losses and flush out Carbon Monoxide in the Argon Oxygen Decarburization (AOD) process.
Used in ladle stirring, vacuum arc degassing and metal stream shrouding
Argon is used as a Fire extinguishing gas
It is used as for providing a protective atmosphere for old documents to prevent their degradation in storage
It is used as an asphyxiating agent in poultry.