IFP Energies nouvelles, Rond-point de l'échangeur de Solaize, BP 3, 69360 Solaize, France.
J Chromatogr A. 2013 Mar 8;1280:98-103. doi: 10.1016/j.chroma.2012.12.059. Epub 2013 Jan 14.
The development of efficient conversion processes requires extended knowledge on vacuum gas oils (VGOs). Among these processes, hydrocracking is certainly one of the best suited to meet the increasing demand on high quality diesel fuels. Most of refractory and inhibiting compounds towards hydrocracking and especially nitrogen containing compounds are contained in a fraction of the VGO called the resin fraction, which corresponds to the most polar fraction of a VGO obtained by liquid chromatography (LC) fractionation on a silica column. However, the lack of resolution observed through existing analytical methods does not allow a detailed characterization of these fractions. A recent study showed that comprehensive high temperature two-dimensional gas chromatography (HT-GC×GC) methods could be optimized in order to elute heavy compounds. This method was implemented for the analysis of VGO resin fractions and complete elution was reached. Firstly, the method was validated through repeatability, accuracy, linearity and response factors calculations. Four VGO resin fractions were analyzed and their HT-GC×GC simulated distillation curves were compared to their GC simulated distillation (GC-SimDist) curves. This comparison showed that the method allows complete elution of most of the analyzed VGO resin fractions. However, a detailed characterization of these fractions is not yet obtained due to the very large number of heteroatomic and aromatic species that a flame ionization detector can detect. Current work aims at increasing the selectivity of GC×GC by using heteroatom selective detectors in order to improve the characterization of such products.
高效转化工艺的发展需要扩展对减压瓦斯油（VGO）的了解。在这些工艺中，加氢裂化无疑是最适合满足高质量柴油燃料需求增长的工艺之一。大多数加氢裂化的难处理和抑制性化合物，特别是含氮化合物，都包含在 VGO 的一个馏分中，称为树脂馏分，它对应于通过硅胶柱液相色谱（LC）馏分法获得的 VGO 的最极性馏分。然而，现有分析方法观察到的分辨率不足，不允许对这些馏分进行详细的表征。最近的一项研究表明，可以优化综合高温二维气相色谱（HT-GC×GC）方法，以洗脱重质化合物。该方法用于分析 VGO 树脂馏分，并实现了完全洗脱。首先，通过重复性、准确性、线性和响应因子计算验证了该方法。分析了四个 VGO 树脂馏分，并比较了它们的 HT-GC×GC 模拟蒸馏曲线和 GC 模拟蒸馏（GC-SimDist）曲线。这种比较表明，该方法允许对大多数分析的 VGO 树脂馏分进行完全洗脱。然而，由于火焰离子化检测器可以检测到大量的杂原子和芳香族物质，因此还无法获得这些馏分的详细表征。目前的工作旨在通过使用杂原子选择性检测器来提高 GC×GC 的选择性，以改善对这些产品的表征。
