Gas Chromatography of Fatty Acids Having Triple Bonds

Abstract

Fatty acids containing one triple bond (such as stearolic and behenolic acid) show a considerable delay on polar separating liquids (such as polyester) compared to the corresponding saturated fatty acids, because of their higher degree of polarity. All considerations indicate that the extent of this delay is greater than that of the fatty acids containing one double bond (such as oleic acid, erucic acid, etc.) or two double bonds (such as linoleic acid). The effect is reversed when non-polar separating liquids are employed; on these, fatty acids containing triple bonds move faster than the corresponding saturated fatty acids. The elution times of fatty acids containing one triple bond are nevertheless greater than the retention times of fatty acids containing one double bond. The values of the separation factors for the -CH₂- group differ very little for the three series of fatty acids (saturated, containing one double bond, and containing one triple bond) investigated.