二异丁烯中硫化物色谱测定时样品溶剂效应的影响及对策  

INFLUENCE OF SAMPLE SOLVENT ON CHROMATOGRAPHIC DETERMINATION OF SULFIDE IN DIISOBUTYLENE AND ITS COUNTERMEASURES

作　　者：吴明清[1] 李涛[1] 朱忠鹏[1] 伏朝林 Wu Mingqing;Li Tao;Zhu Zhongpeng;Fu Zhaolin(SINOPEC Research Institute of Petroleum Processing,Beijing 100083)

机构地区：[1]中国石化石油化工科学研究院,北京100083

出　　处：《石油炼制与化工》2021年第1期92-102,共11页Petroleum Processing and Petrochemicals

基　　金：中国石油化工股份有限公司合同项目(117011-2)。

摘　　要：气相色谱与硫化学发光检测器的组合(GC-SCD)可用于检测烃液中的硫化物。然而在配置PONA色谱柱的GC-FID-SCD仪器上测定二异丁烯工业品中的硫化物时,发现二异丁烯对部分硫化物的色谱测定存在严重的溶剂效应,使色谱峰无法识别。详细研究了二异丁烯进样量对石化产品中可能存在的硫醚、二硫化物及噻吩等的色谱峰性质的影响;以样品稀释-外推法预测无二异丁烯影响时硫化物保留时间,再以标样加入法获得确认。研究结果显示:在二异丁烯主要组分附近出峰的硫化物受影响较大;二乙基硫醚提前0.041 min出峰且峰宽增加2倍,甲基叔丁基硫醚的保留时间延后0.443 min且峰宽增加9倍以上,二甲基二硫的出峰时间延后0.377 min且峰宽增加1倍,甲基仲丁基硫醚延后0.179 min出峰;对远离溶剂出峰的硫化物影响较小。采用稀释-外推为主的方法识别出二异丁烯工业样品中的硫化物,主要是甲基叔丁基硫醚、乙基叔丁基硫醚、二叔丁基硫醚、二叔丁基二硫等含有异丁基的硫醚或二硫化物。The combination of gas chromatography(GC)and sulfur chemiluminescence detection(SCD)is a high effective method for analyzing sulfur compounds in hydrocarbon samples.A GC-SCD-FID combined instrument equipped with a PONA column was employed to determine sulfides in samples of synthesis diisobutylene(DIB).However,it was difficult to identify some SCD peaks due to solvent effects from DIB by the method.The influence of diisobutylene injection amount on the chromatographic peak properties of sulfide,disulfide and thiophene that may exist in petrochemical products was studied in detail.The retention time of sulfides without diisobutylene were predicted by sample dilution-extrapolation,and then confirmed by standard sample addition method.It was shown that the sulfide peaks appeared near the diisobutylene were greatly affected:The appearance time of diethyl sulfide peaks was 0.041 min earlier and the peak width increased by 2 times,the methyl tert-butyl sulfide retention time was prolonged by 0.443 min and the peak width increased by more than 9 times,the dimethyl disulfide peak time was prolonged by 0.377 min and the peak width was doubled,and the retention time of methyl sec-butyl sulfide was prolonged by 0.179 min.However,little effect on sulfide far away from the peak of solvent was found.Sulfides in diisobutylene samples identified by dilution-extrapolation method were mainly methyl tert-butyl sulfide,ethyl tert-butyl sulfide,di-tert-butyl sulfide,di-tert-butyl disulfide and other sulfides or disulfide containing isobutyl.

关 键 词：毛细管气相色谱 二异丁烯 有机硫化物 溶剂效应 色谱峰变形 保留时间漂移 

分 类 号：TQ221.213[化学工程—有机化工] O657[理学—分析化学]