柴油烃族组成分布的GC-MS测定

应用GC－MS测定柴油烃族组成按沸点的分布，通过柱色 谱分离后的柴油饱和烃和芳烃组分分别进入气相色谱－质谱联用仪分析，采集其每一扫描的质谱图后，按ASTM－D2425方法计算其每一扫描的烃族组成，因为每一扫描与保留时间对应，所以可将两部分烃族组成加和后应用ASTM－D2887方法计算柴油烃族组成按沸点的分布规律；实验结果表明，该法与ASTM－D2887和ASTM－D2425的实验结果吻合，并能给出有关柴油烃族组成的详尽分布规律。

Determination of Hydrocarbon Types in Intermediate Fractions by GC- MS

A GC-MS method is described for the determination of oil composition by hydrocarbon types in intermediate fractions. Oil samples were fractionated by LC into three fractions, namely, alkanes, aromatics and residues. Then the alkane fraction and the aromatic fraction were injected separately into the GC-MS. The hydrocarbon composition of the sample was then determined for each scan. Altogether 11 types of hydrocarbons were identified according to the ASTM _ D2425 method. Since each scan corresponds to a retention time, the retention times can be related to the boiling points of these hydrocarbons. Consequently, it is reasonable to use the ASTM _ D2887 method for the calculation of different hydrocarbon types. Our results agree with those obtained by ASTM _ D2887 and ASTM _ D2425 methods. The proposed method can give detailed information on the distribution of hydrocarbons in the distillation fractions that any other methods cannot provide.