采用化学萃取法结合GC/双火焰光度检测器技术,研究了碱洗、固定床脱臭和液-液脱臭等脱硫醇工艺中加氢精制重汽油中硫醇类型的变化规律.实验结果表明,加氢精制重汽油中硫醇以C6及C6以上硫醇为主,C6及C6以上硫醇硫质量占总硫醇硫质量的92.1％；碱洗前后加氢精制重汽油中硫醇的种类相同,但各硫醇单体的相对含量发生变化,碱洗后J正戊硫醇和正己硫醇的相对含量降低,而C6异构硫醇及C6以上硫醇的相对含量增加；采用不同脱臭工艺或不同深度脱臭处理后,加氢精制重汽油中的硫醇都以苯硫酚和C7及C7以上硫醇为主,苯硫酚和C7及C7以上硫醇硫的质量占总硫醇硫质量的81％～91％,表明大分子硫醇的脱除较为困难,脱臭过程中大分子硫醇的脱除是关键.%Variation of the thiol types in the heavy fractions of hydrotreated gasoline in several different sweetening processes (caustic wash process, fixed-bed sweetening process and liquid-liquid sweetening process) was studied by extraction and gas chromatography with flame photometric detector. The results showed that the thiols in the heavy fractions of hydrotreated gasoline were mainly the thiols with more carbon atoms than 5 , which almost contained 92.1% of the total thiol sulfur. The thiol types in the heavy fractions of hydrotreated gasoline before and after caustic wash were almost similar, but the relative contents of every thiol were changed. After the caustic wash, the contents of n-pentanethiol and n-hexylmercaptan decreased, while the content of isomeric C6 thiol and higher thiols than C6 increased. Thiols in the heavy fraction of gasoline after treated by different sweetening processes with different sweetening degree were mainly thiophenol and higher thiols than C6, and their amount was 81% -91% , which revealed that removal of the thiols with high relative molecular mass was difficult. Therefore,the removal of thiols with higher relative molecular mass in sweeting is crucial.
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