Analysis of Hydrocarbons

Abstract

THE difficulty of separating a mixture of ethane, ethylene, propane and propylene on a single column in gas-phase chromatography has been commented on recently¹. Drs. Barnard and Hughes also mention the difficulty of using some two-stage columns. This mixture can in fact be readily separated on a single column. If it is required to analyse only small samples, a column packed with alumina may be used, either thermostatted at one temperature² or by ‘temperature-programming’ the column³. When both small and large samples have to be analysed, it is an advantage to use gas – liquid chromatography, and a single column of dimethylsulpholane on firebrick may be used⁴. Two-stage columns have also been used successfully to carry out this separation⁴; further, a commercial column is manufactured with which this analysis can be carried out⁵.