地质样品正构烷烃组分分离纯化的部分问题探究.pdf

2011年2月
岩矿测试
Vol 30. No
February 2011
ROCK AND MINERAL ANALYSIS
文章编号:0254-5357(2011)01-000-06
地质样品正构烷烃组分分离纯化的部分问题探究
王欢业,刘卫国'“,张普…2
1.中国科学院地球环境硏究所黄土与第四纪国家重点实验室,陕西西安710075;
2.中国科学院研究生院,北京100049;3.西安交通大学人居与环境学院,陕西西安710049)
摘要:用实验室自配的标准正构烷烃样品分别经硅胶或氧化铝柱层析后发现,等量溶剂洗脱的情况下硅胶对长
链正构烷烃无吸附而氧化铝具有一定吸附性。进一步通过用植物样品测试4种层析柱填充方法,发现不论是只
用氧化铝填充还是上部硅胶下部氧化铝和上部氧化铝下部硅胶,都会对长链正构烷烃产生一定的吸附,且这种吸
附效果随看碳链的増长而増强。在实验条件下,当碳链加长到C2时,用硅胶加氧化铝填充层析柱的吸附量已达
到20%左右,而只用氧化铝填充层析柱的吸附量则高达50%。故建议对研究高碳数正构烷烃的地质样品组分提
取时用单一的硅胶柱层析方法。同时,实验显示对于一些杂质多的正构烷烃样品经过尿素络合后比络合前“干
净”得多。18个黄土ー古土壤和植物样品平均回收率为50%左右,经过尿素络合后的样品正构烷烃各组分相对
含量基本不会发生改变,也不会产生明显的同位素分馏效应。因此在进行非正构组分千扰较大的正构烷烃各组
分相对含量或同位素分析时,可以选择尿素络合的方法来将其纯化。
关键词:正构烷烃;地质样品;柱层析填充材料;尿素络合
中图分类号:0623.1
文献标识码:A
Exploration of Some Problems in the Separation and Purification of
n-alkanes in Geological Samples
WANG Huan-ye, LIU Wei-guo., ZHANG Pu
(1. The State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment
Chinese Academy of Sciences, Xi'an 710075, China
Graduate School of Chinese Academy of Sciences, Beijing 100049, China
3. School of Human Settlement and Civil Engineering, Xi'an Jiaotong University, Xi'an 710049, China
Abstract: Adsorption characteristics of silica gel and alumina for n-alkanes were tested by column chromatography under
equivalent solvent elution. The results showed that alumina could adsorb long chain n-alkanes in certain extent, while
silica gel exhibited the opposite characteristic. The further experiments using plant samples and chromatographic columns
filled with different materials were carried out. The experiment results indicated whether the columns filled with alumina
and silica gel or with alumina alone, it exhibited adsorption characteristics for long chain n-alkanes and the adsorption
effect became explicit with increasing of length of carbon chain. Under the proposed experiment condition, when the
hain length reached Cao, adsorbed amounts by the columns filled with silica gel-alumina and with alumina alone
reached up to 20% and 50%, respectively. Therefore, silica gel chromatographic column could be the beller choice
when long chain n-alkanes in geological samples were analyzed Moreover, the experiment results also indicated that
收稿日期:2010-01-15;修订日期:2010-06-23
基金项目:国家重点基础研究发展计划项目(973计划)基金资助(2010CB833403);国家自然科学基金项目资助(40873011)
作者简介:王欢业(1986-),男,山东烟台人,硕士研究生,环境科学专业,研究方向为稳定同位素地球化学。F-mil: why(@ mail.ustc.du.ecno
通讯作者:刘卫国(1958-),男,陕西长安人,研究员,从事同位素生物地球化学研究。E-mail:liuwa@loes.lig.ac.cno