摘要
测定了61个不同类型化合物在6根PEG20M石英毛细管柱上的保留指数(RI),结果表明各柱间RI存在相当大的差异,给RI数据库的应用带来了困难,结合文献数据,从固定液本身、相界面吸附、热力学函数及柱极性的表征等方面探讨其原因,认为以烷烃为主的相界面吸附是影响RI可比性的重要因素,同时柱制备过程带来的影响也不容忽视。
ovats retention indices (RI) of sixty-one compounds of different structural types were measured on six PEG 20M fused silica capillary columns and it was shown that RI difference among these columns is so large that RI database is hard to be applied directly. The maximum difference in RI was found between column 1 and column 3. The average differences in RI between these two columns were 72. 8 i. u.for all of the sixty-one compounds and 63.6, 77.6, 73.9, 63.3, 76.7 and 75.6 i. u. for aromatic hydrocarbons, alcohols, ketones, esters,chloro-compounds and others respectively. The reasons of poor comparability for RI among PEG 20M columns were investigated aganist stationary phase property, adsorption on interfaces between gas-liquid and solid-liquid phases, thermodynamic functions and polarity of column. The conclusion is that adsorption on interfaces is the factor which mainly affects RI comparability due to its influence on the retention value of normal paraffins which are used in the calculation of RI and the influence from preparation of column can not be ignored either.
出处
《色谱》
CSCD
北大核心
1996年第3期163-167,共5页
Chinese Journal of Chromatography
关键词
气相色谱
保留指数
数据库
毛细管柱
gas chromatography
retention index
universal database
polyethylene glycol 20M capillary column