Hydrogen (H2)
Hydrogen is the lightest of all gases, colourless, highly flammable and only found in trace quantities in the atmosphere. It issynthesized from hydrocarbons (petroleum and petroleum by-products) and from water where it constitutes the lightest fraction of the H₂O molecule. Major uses of hydrogen include the production of synthetic ammonia and methanol, petroleum refining, the hydrogenation of organic materials, oxyhydrogen torches, and in rocket fuels.
|
Properties |
U.S. Units |
S.I. Units |
|
Chemical formula |
H₂ |
H₂ |
|
Molecular weight |
2.016 |
2.016 |
|
Density of the gas at 70°F (21.1°C) and 1 atm. |
0.00521 lb/ft3 |
0.08342 kg/m3 |
|
Specific gravity of the gas at 70°F (21.1°C)and 1 atm (air=1) |
0.0696 |
0.0696 |
|
Specific volume of the gas at 70°F (21.1°C) and 1 atm |
192.0 ft3/lb |
11.99 m3/kg |
|
Melting point at 1 atm |
-434.55°F |
-259.2°C |
|
Critical temperature |
-399.93°F |
-239.96°C |
|
Critical pressure |
190.8 psia |
1316 KPa,abs |
|
Critical density |
1.88 lb/ft3 |
30.12 kg/m3 |
|
Boiling point at 1 atm |
-422.97°F |
-252.76°C |
|
Solubility in water vol/vol at 32°F(0°C) & 1 atm. |
0.019 |
0.019 |
|
Industry |
Usage |
|
Food and beverage |
Used in the hydrogenation of amines and fatty acids |
|
Glass |
Used in the float glass process Used in the heat treatment (oxyhydrogen flame) of hollow glass and optic fibres pre-forms. |
|
Metal fabrication |
Heat treatment of various metals |
|
Electrical |
Atmospheric reduction in microchip production. |
|
Automotive |
Hydrogen is a carbon free energy source used in fuel cells. |
|
Laboratories |
Used as a carrier gas in gas chromatography and in various analytical instrument applications most commonly as a fuel component of combustion gases for Flame Ionization (FID) and Flame Photometric (FPD) detectors. Spark discharge analysers and total hydrocarbon measurements also use hydrogen mixtures. |
|
Grade |
Cylinder type |
Pressure (Barg) |
|
4.5 |
50L |
200 |
|
40L |
150 |
|
|
6.0 |
50L |
200 |
|
40L |
150 |
|
|
5.5 |
50L |
200 |
|
40L |
150 |
|
|
5.0 |
50L |
200 |
|
40L |
150 |
|
Specification Grade |
Impurities (ppmv) |
Certification Specification |
||||
|
H2O |
O2 |
N2 |
CO / CO2 |
CnHm |
||
|
4.5 |
5 |
10 |
5 |
|
|
* |
|
6.0 |
< 0.5 |
< 0.1 |
< 0.2 |
< 0.05 |
< 0.05 |
* |
|
5.5 |
< 2.0 |
< 0.5 |
< 2.0 |
< 0.5 |
< 0.5 |
* |
|
5.0 |
< 5 |
< 2 |
< 4 |
< 0.5 |
< 0.5 |
* |
* Supplied with certificate of analysis