›› 2018, Vol. 49 ›› Issue (1): 83-87.

• 分析与评定 • 上一篇    下一篇

液液萃取-气相色谱-氧选择性检测法测定柴油中的酚类化合物

李长秀,钱钦,金珂,吴梅,孔翠萍   

  1. 中国石化石油化工科学研究院
  • 收稿日期:2017-07-11 修回日期:2017-07-23 出版日期:2018-01-12 发布日期:2018-01-24
  • 通讯作者: 李长秀 E-mail:licx.ripp@sinopec.com

DETEEMINATION OF PHENOLIC COMPOUNDS IN DIESELS USING LIQUID-LIQUID EXTRACTION AND GC-OXYGEN SELECTIVE DETECTOR

  • Received:2017-07-11 Revised:2017-07-23 Online:2018-01-12 Published:2018-01-24
  • Contact: LI Chang-Xiu E-mail:licx.ripp@sinopec.com

摘要: 建立了液液萃取结合气相色谱-氧选择性检测器(GC-OFID)测定柴油样品中微量酚类化合物的方法。待测试样经10%的氢氧化钠溶液萃取,水相经稀盐酸调至pH=5~6后,用二氯甲烷反萃取其中的酚类化合物,挥发溶剂后得到浓缩的酚类富集物,然后进行GC-MS和GC-OFID检测。通过与GC-MS检测结果对比,结合各酚类组分的沸点和色谱峰保留规律,确定了GC-OFID上54个(组)色谱峰对应的酚类化合物的结构或类型。在酚类富集物中加入已知量的苯甲醇作内标物,采用内标法进行定量。在样品量为50 mL时,测定苯酚、2,5-二甲基苯酚、2,3,5-三甲基苯酚的检测限分别为0.5,1.0,1.5 μg/mL,在质量浓度8~40 μg/mL范围内连续5次重复性测定结果的相对标准偏差均小于8.0%,可以用于柴油中酚类化合物的测定。

关键词: 酚类化合物, 柴油, 氧选择性检测器, 气相色谱

Abstract: A method for determination of phenolic compounds in diesels was established by using liquid-liquid extraction combined with gas chromatograph equipped with oxygen selective flame ionization detector(GC-OFID). Diesel samples were first extracted with 10% sodium hydroxide. The extracted water phase was neutralized to Ph 5-6 with dilute hydrochloric acid and then re-extracted with dichloromethane. The phenolic compounds-containing dichloromethane were evaporated to get concentrated phenolic compounds and were then detected by GC-MS and GO-OFID. The structures or types of 54 peaks or groups of phenolic compounds were identified by GC-MS, chromatography retention time and boiling points. Benzyl alcohol was added into the concentrated samples as internal standard for quantification test. When 50 mL diesel sample is treated,the detection limits of phenol,2,5-dimethyl-phenol and 2,3,5-trimethyl phenol are 0.5,1.0,1.5 mg/L respectively. The relative standard deviations of five consecutive results are less than 8.0% in the phenolic compound concentration range of 8-40 mg/L,which meet the requirement of routine analysis.

Key words: phenolic compounds, diesel, oxygen selective flame ionization detector, gas chromatography