Abstract:

To obtain detailed information on the hydrocarbon components in heavy alkyl benzene （HAB）, in this study, comprehensive two-dimensional gas chromatography （GC×GC） was utilized for qualitative and quantitative analysis of HAB. An analytical system based on GC×GC technology was established, enabling efficient separation according to categories of alkenes-plus-alkanes, linear alkyl benzenes （LAB）, monocyclic aromatics, and bicyclic aromatics in HAB through a single injection. Simultaneously, qualitative identification and quantitative analysis of each component were achieved. The results showed that the hydrocarbon fractions of HAB primarily consisted of alkenes-plus-alkanes, LAB, monocyclic aromatics, and bicyclic aromatics. Using the established method, the content of each category, i.e., alkenes-plus-alkanes, LAB, monocyclic aromatics and bicyclic aromatics, was determined for three HAB samples （designated as HAB-1, HAB-2, and HAB-3）. Based on chromatographic peak area: LAB exhibited the highest mass fractions in three samples （94.05% in HAB-1, 84.59% in HAB-2, and 66.43% in HAB-3）. Based on carbon number distribution: The peaks of HAB-1 mainly distributed in the range of C₁₇-C₂₈; the peaks of HAB-2 mainly distributed in the range of C₁₉-C₃₃; the peaks of HAB-3 mainly distributed in the range of C₂₇-C₅₀. Compared with traditional one-dimensional gas chromatography （GC）, GC×GC demonstrated significant technical advantages and broad application prospects in separating complicated mixtures due to its enhanced peak capacity and superior resolution. This method could provide technical support for in-depth understanding of hydrocarbon composition in HAB.

Key words: comprehensive two-dimensional gas chromatography, heavy alkyl benzene, hydrocarbon group composition, carbon number distribution