双通道GC-SCD系统测定乙烯和丙烯气体中痕量硫化物

Dual-channel GC-SCD system for determination of trace sulfur compounds in ethylene and propylene

建立了一种采用双通道气相色谱-硫化学发光检测器(GC-SCD)系统分析乙烯、丙烯中痕量硫化物的方法。考察了硫化物在双通道系统的分离效果以及方法的重复性、准确性,并比较了色谱柱的惰性。实验结果表明,该方法可实现硫化氢、羰基硫、甲硫醇、乙硫醇、甲硫醚和乙硫醚6种硫化物的分离和定量,避免了单根色谱柱的烃类干扰问题。该方法的重复性好,含量在0.1~1μmol/mol以下硫化物组分的相对标准偏差在10%以内,回收率在80%~120%之间,灵敏度高,检测限可达30 nmol/mol。

A dual-channel gas chromatography coupled with sulfur chemiluminescence detection(GC-SCD)system was introduced for the determination of trace sulfur compounds in ethylene and propylene.The separation,repeatability,and accuracy of this dual-channel GC-SCD method were verified,and a comparison of the inertness of two columns was conducted.In this paper,six sulfur compounds,including hydrogen sulfide,carbonyl sulfide,methyl mercaptan,ethyl mercaptan,dimethyl sulfide,and diethyl sulfide,were proven to be effectively separated and quantified,without matrix interferences from hydrocarbons typically seen in a single column analysis.The results indicate that the relative standard deviations are less than 10%for sulfur compounds content 0.1-1μmol/mol.Additionally,the method demonstrates high accuracy,with recoveries of the sulfur compounds ranging from 80%-120%and the detection limits of 30 nmol/mol.