Improved hydrocarbons analysis of heavy petroleum fractions by high temperature comprehensive two-dimensional gas chromatography

Conventional comprehensive two-dimensional gas chromatography (2D-GC or GC x GC) is now widely used for middle distillates analysis; only a few applications are devoted to heavy fractions such as vacuum gas oils or vacuum residues. A recent extension of GC x GC range in suitable high temperature conditions allowed quantitative analysis of a full vacuum gas oil (VGO) up to nC(60). Considering this study as a new breakthrough for the challenge of heavy petroleum fractions analysis, the application of high-temperature two-dimensional gas chromatography (HT-2D-GC) to 12 VGOs from different origins (geographic and processes) and one de-asphalted oil (DAO) is described in this paper. The comparison with standardized methods, liquid chromatography and mass spectrometry, illustrates the reliability of the method for heavy cuts analysis. Furthermore, quantitative distributions by chemical families could be built for the first time, which allow a better description and more relevant comparisons between heavy petroleum fractions. Except for heavier cuts such as DAO, this powerful technique is widely applicable on VGO fractions. These results should increase the analytical information concerning heavy cuts and will be helpful to understand reactions involved in petroleum processes. (C) 2009 Elsevier Ltd. All rights reserved.