Product name: Argon

CAS: 7440-37-1

Molecular formula: Ar

Molecular weight: 39.95

EINECS: 231-147-0

Introduction

Argon is a noble gas with the chemical symbol Ar and the atomic number 18. It is in the 18th group of the periodic table. It accounts for 0.934% of the atmospheric volume (9340 ppmv), making it the third most abundant gas in the Earth's atmosphere, more than twice that of water vapor (average 4000 ppmv, but with great variation), 23 times that of carbon dioxide (400 ppmv), and more than 500 times that of neon (18 ppmv). Argon is the most abundant noble element in the Earth's crust, accounting for 0.00015% of the Earth's crust. There are 14 known isotopes of argon, ranging from argon 33 to argon 46. Most of the argon in the Earth's atmosphere is argon-40 (argon-40 decays from potassium-40 in the Earth's crust). Argon-36 is the most common argon isotope in the universe because it is the most easily produced product of supernova nuclear fusion.

Argon Properties

Chemical properties

The most abundant rare gas in the air. Colorless, tasteless, odorless. Soluble in water, with a solubility of 5.6g/cm3 water at 0℃. Also soluble in ethanol.

Sources

Argon is the 56th most abundant element on Earth. It is the most abundant of all the noble gases in the atmosphere. In fact, the only source of argon is the atmosphere, where it accounts for slightly less than 1% by volume.

Uses

1. Commonly used as an inert protective gas to fill various types of bulbs

2. Used as a protective gas for rare metal smelting, filling electron tubes and bulbs, etc.

3. Used as carrier gas, zero gas, standard gas, calibration gas for chemical, metallurgical, gas chromatography and other instruments, and can also be used in semiconductor device manufacturing

4. Used as a filling gas in the bulb industry

5. Mainly used for metal welding and cutting, such as welding and cutting of light metals, stainless steel or special alloy steel. The most commonly used is argon arc welding with argon as a mist atmosphere. Used in semiconductor refining, 5% hydrogen and 95% argon mixed gas is often used in industry as a protective atmosphere for silicon semiconductor refining. Used in metal smelting, when smelting titanium, zirconium and other metals, it is necessary to carry out reduction reactions in an inert protective atmosphere such as argon. It is also used as a degasser for smelting special steels. Application in plasma, a mixture of argon and hydrogen can be used as plasma in magnetohydrogen power generation and electric light sources.

6. Inert gas for packaging.

Applications

Argon is used when an inert atmosphere is required. It can be used alone or mixed with other inert gases to fill electric light bulbs, fluorescent tubes, lasers, etc. By replacing the oxygen in an incandescent bulb, it prevents oxygen from corroding the filament of the bulb. It is also used as a non-oxidizing gas when welding and as a decarburizer for steel, as well as an inert atmosphere for growing semiconductor crystals in it.

Production method

The air separation method extracts the argon-containing fraction from the air during oxygen production, passes through an argon tower to produce crude argon, then adds hydrogen to remove oxygen from the crude argon, and produces 99.99% to 99.999% high-purity argon after distillation and denitrification. The extraction of argon from synthetic ammonia tail gas can be divided into two categories: low-temperature separation of tail gas discharged after synthesis and low-temperature separation of liquid nitrogen washing before the synthesis gas enters the synthesis tower. The raw gas of the low-temperature separation process is purified, partially condensed or distilled to separate hydrogen and nitrogen, separation of methane, and separation of argon and nitrogen mixtures, and 99.999% pure argon can be produced.