Zhang Cheng, Ingram Isaiah C, Hantao Leandro W, Anderson Jared L
Department of Chemistry and Biochemistry, The University of Toledo, Toledo, OH 43606, USA.
Laboratório de Microfabricação (LMF), Laboratório Nacional de Nanotecnologia, Centro Nacional de Pesquisa em Energia e Materiais, Campinas, São Paulo 13083-970, Brazil.
J Chromatogr A. 2015 Mar 20;1386:89-97. doi: 10.1016/j.chroma.2015.01.074. Epub 2015 Feb 2.
A series of dicationic ionic liquid (IL)-based stationary phases were evaluated as secondary columns in comprehensive two-dimensional gas chromatography (GC×GC) for the separation of aliphatic hydrocarbons from kerosene. In order to understand the role that structural features of ILs play on the selectivity of nonpolar analytes, the solvation parameter model was used to probe the solvation properties of the IL-based stationary phases. It was observed that room temperature ILs containing long free alkyl side chain substituents and long linker chains between the two cations possess less cohesive forces and exhibited the highest resolution of aliphatic hydrocarbons. The anion component of the IL did not contribute significantly to the overall separation, as similar selectivities toward aliphatic hydrocarbons were observed when examining ILs with identical cations and different anions. In an attempt to further examine the separation capabilities of the IL-based GC stationary phases, columns of the best performing stationary phases were prepared with higher film thickness and resulted in enhanced selectivity of aliphatic hydrocarbons.
一系列基于双阳离子离子液体（IL）的固定相被评估用作全二维气相色谱（GC×GC）中的第二根色谱柱，用于分离煤油中的脂肪烃。为了理解离子液体的结构特征对非极性分析物选择性的影响，采用溶剂化参数模型探究基于离子液体的固定相的溶剂化性质。观察到，含有长游离烷基侧链取代基以及两个阳离子之间长连接链的室温离子液体具有较小的内聚力，并且对脂肪烃表现出最高的分离度。离子液体的阴离子成分对整体分离没有显著贡献，因为在研究具有相同阳离子和不同阴离子的离子液体时，观察到对脂肪烃具有相似的选择性。为了进一步考察基于离子液体的气相色谱固定相的分离能力，制备了具有更高液膜厚度的最佳固定相色谱柱，其对脂肪烃的选择性增强。
