碱液萃取前后原油中酸性化合物组成的高分辨质谱分析  

Composition and Distribution of Acidic Compounds in Duba Extracts:Revealed by Negative Electrospray Ionization-Fourier Transform Ion Cyclotron Resonance-Mass Spectrometry

作　　者：陆小泉[1] 史权[1] 赵锁奇[1] 高金森[1] 张亚和[1] 何俊辉[1] 

机构地区：[1]中国石油大学(北京)重质油国家重点实验室,北京102200

出　　处：《分析化学》2008年第5期614-618,共5页Chinese Journal of Analytical Chemistry

基　　金："973"基金(No.2004CB217801)资助项目

摘　　要：采用改进的碱液萃取方法分离杜巴原油中的酸性化合物(主要是环烷酸),通过高分辨质谱分析萃取过程中不同组分酸性化合物组成,以研究碱萃取前后酸性化合物的分布与组成特征。实验结果表明,电喷雾傅立叶变换离子回旋共振高分辨质谱(ESI-FT-ICR-MS)是分析原油中酸性化合物的强有力的手段;酸性化合物分布于碱萃取前后的各个组分中,但其组成有明显的差异,碱液萃取出的石油酸主要是相对分子质量小于500的酸性组分,增加反萃取溶剂的用量和极性有利于脱除萃取物中的非碱性氮化合物,对石油羧酸的组成影响不大。A modified version of base extraction was adopted to separate the acidic compounds, primarily naphthenic acids, in Duba crude oil. Extracts and residua were collected and subsequently characterized by negative electrospray Fourier transform ion cyclotron resonance mass spectrometry （ Neg ESI FT ICR MS）. The results indicated that Neg ESI FT ICR MS was a powerful tool for the identification of acidic compounds in crude oil. The broadband mass spectra showed that acidic compounds distributed in all the fractions of extrac- tion, and obviously differed in composition and relative abundance. The washing process could only extract the acidic portion with a molecular lower than 500 Da. Increasing in solvent volume and in polarity of reverse- extracting solvent tended to exclude more neutral nitrogen compounds. Meanwhile, this procedure had little influence on the composition and distribution of acidic compounds with a relatively low molecular weight.

关 键 词：原油 碱液萃取 石油酸 电喷雾-傅立叶变换-离子回旋共振质谱(ESI-FT-ICR-MS) 

分 类 号：TE622.1[石油与天然气工程—油气加工工程]