Abstract:

The method for the separation and determination of sulfur compounds in coked gasoline by gas chromatography-sulfur chemiluminescence detection (GC-SCD) was established. Seventy-four sulfur compounds including hydrogen sulfide, mercaptans, sulfides, disulfides, thiophene, alkyl thiophenes, benzothiophene, alkyl benzothiophenes in a coked gasoline sample were identified by standard samples and past identified results. The retention indexes of different sulfur compounds in coked gasoline under programmed temperature condition were calculated based on the retention times of hydrosulfide, ethyl mercaptan, n-propyl mercaptan, thiophene, 2-methyl thiophene, 2-ethylthiophene, 2-propylthiophene, C4-thiophene (tR=40.28 min), benzothiophene, and methylbenzothiophene (tR=58.13 min). The relative standard deviations of the determination results of main sulfur compounds (isopropyl mercaptan, n-propyl mercaptan, n-butyl mercaptan, 2-methylthiophene, 3-methylthiophene, 2,4-dimethylthiophene, 2,3,4-trimethylthiophene) in coked gasoline were less than 5%, and the detection limit for sulfur was 0.05 mg/L. The linear range of sulfur was 0.2-400 mg/L for each sulfur compounds（r2=0.999）. The contents of sulfur compounds, especially the content of mercaptan, are much more than those in the catalytic gasoline. There is also a big difference in the sulfur contents between 2-methylthiophene and 3-methylthiophene. The data can be useful for the study of hydrodesulfurizing catalyst and industrial process planning.

Key words: coked gasoline , sulfur compound distribution, gas chromatography-sulfur chemiluminescence detection （GC-SCD）