Methane is a colorless, odorless, tasteless, flammable gas. It is the first member of the paraffin (aliphatic or saturated) series of hydrocarbons. It is the major constituent of natural gas. Methane is soluble in alcohol or ether, and slightly soluble in water.
Methane is shipped as a nonliquefied compressed gas in cylinders at pressures up to 6000 psig at 70oF (41 370 kPa at 21.1oC). Liquefied methane (as natural gas-LNG) is shipped in bulk quantities as a cryogenic liquid on barges and tankers. Methane is a major constituent of coal gas and is present to an extent in air in coal mines.
Methane is typically available for commercial and industrial purposes in a C.P. Grade (minimum purity of 99 mole percent), a technical grade (minimum purity of 98.0 mole percent), and a commercial grade that is actually natural gas as it is received from the pipeline. (There is no guaranteed purity, but methane content usually runs about 93 percent or better.) Tertiary-butyl mercaptan is added in trace amounts as an odorant. This grade of gas has a sulfur content of 0.002 grains/100 ft3 (0.0457mg/m3) and a typical gross heating value of 1044 Btu/ft3 (38 898 kJ/m3). (416 kPa).
Methane is produced commercially from natural gas by absorption or adsorption methods of purification; supercooling and distillation are sometimes employed to secure methane of very high purity. Some California natural gas wells produce methane of high purity. It can also be obtained by …more