Determination of Methane in Water by Gas Chromatography

Gas chromatography has been applied to the determination of dissolved gases in water, including methane. This article describes a system that can be easily fabricated from any standard gas chromatograph with a flame ionization detector. The methane is stripped from water by means of a carrier gas and analyzed in the chromatograph. The method is capable of detecting methane in water in concentrations as low as 0.02 mg /l. Any ethane in the sample would be resolved by the gas chromatograph and appear as a separate peak with a different retention time. The flame ionization detector does not respond to dissolved permanent gases or other inorganic contaminants.