双通道三色谱柱气相色谱法测定成品车用汽油详细组成  

Determination of individual components in finished motor gasoline by dual⁃channel three⁃column gas chromatography

作　　者：李长秀 王亚敏 张祎玮 王征 LI Changxiu∗;WANG Yamin;ZHANG Yiwei;WANG Zheng(SINOPEC Research Institute of Petroleum Processing Co.,Ltd.,Beijing 100083,China)

机构地区：[1]中石化石油化工科学研究院有限公司,北京100083

出　　处：《色谱》2024年第8期773-782,共10页Chinese Journal of Chromatography

基　　金：中国石油化工股份有限公司科研项目(KL18014).

摘　　要：建立了一套双通道、三柱、三检测器的气相色谱分析系统,用于成品车用汽油的详细组成分析。采用双进样器同时进样方式将试样导入两个色谱进样口,第一个进样口(通道1)的试样中组分经非极性色谱柱(PONA柱)(50 m×0.20 mm×0.5μm)分离,进入火焰离子化检测器(FID)检测;第二个进样口(通道2)的试样组分进入第二根PONA柱分离,依据事先设定的时间表,采用多次中心切割的方式将一些PONA柱上难分离组分的共流出峰切割至DM-624色谱柱(30 m×0.25 mm×1.4μm)上进一步分离,经FID检测。这些难分离的组分包括与烃类共流出的醇醚类含氧化合物,一些汽油标准中禁止人为添加的非常规添加组分如甲缩醛、碳酸二甲酯、乙酸仲丁酯和苯胺类化合物,以及一些关键的难分离物质对如甲苯和2,3,3-三甲基戊烷。第二根PONA色谱柱通过中心切割出口连接一根阻尼柱与第三个检测器相连,以方便地确定合适的中心切割时间表。根据DM-624色谱柱上分离得到的难分离组分的峰面积和通道间的定量校正系数,推算出这些难分离组分在通道1的PONA色谱柱上的共流出峰中所占的色谱峰面积,从而实现共流出色谱峰的拆分。根据通道1的PONA柱上所有色谱峰的峰面积和定性结果,采用校正归一的方法可以得到车用汽油中含氧化合物、非常规添加组分和单体烃质量分数,并进一步计算得到样品的碳数族组成数据,消除了含氧化合物及非常规添加组分与烃类组分间的干扰问题。该方法对实际车用汽油的测定结果与标准方法GB/T 30519-2016、NB/SH/T 0663-2014及SH/T 0693-2000的测定结果有很好的一致性。对于添加有甲缩醛等某些非常规添加组分的样品,采用本方法也可以得到这些非常规添加组分的含量。通过本方法一次分析可以得到需要使用3~4个标准方法才能获得的分析数据,同时可以获得车用汽油的详细单体烃组成信�A method based on a dual-channel gas chromatograph equipped with three columns and three detectors was established for the determination of individual components in finished motor gasoline.The gasoline samples were separately introduced into the two injection ports of the chromatograph using two autosamplers.The components of the sample introduced into the first injection port(channel 1)were separated on a nonpolar PONA column(50 m×0.20 mm×0.5μm)for gasoline analysis and detected by an flame ionization detector(FID).The components of the sample introduced into the second injection port(channel 2)were separated on another PONA column.Oxygenates(e.g.,ethers and alcohols),other unconventional and prohibited additives that would co-elute with the hydrocarbons(e.g.,methylal,dimethyl carbonate,sec-butyl acetate,and anilines),and some difficult-to-separate hydrocarbon pairs(e.g.,2,3,3-trimethylpentane and toluene)eluted from the PONA column and entered a DM-624 column(30 m×0.25 mm×1.4μm)to achieve further separation according to the switch timetable using the Deans switch procedure and detected by an FID.The peak of 3-methylpentane,a common component in gasoline samples,also entered the DM-624 column by the Deans switch procedure for calculation purposes.The peak areas of target components on the PONA column in channel 1 were calculated using the peak areas on the DM-624 column as well as those of 3-methylpentane on both the DM-624 and PONA columns in channel 1 with a calibration factor between the two channels.The peak areas of co-eluted components were obtained by subtracting the calculated peak areas of the target components from those of the co-eluted peaks.The mass percentages of the individual components were calculated according to the normalization method using all peak areas on the PONA column in channel 1 with relative response factors.The mass percentages of the oxygenates,anilines,and individual hydrocarbons were determined,and the group-type distribution was calculated according to the carbon number.S

关 键 词：气相色谱 含氧化合物 苯胺类化合物 车用汽油 详细组成 中心切割 

分 类 号：O658[理学—分析化学]