基于液相色谱的原油组分分离及界面性能研究

Study on separation of crude oil component and interfacial activity based on liquid chromatography

目的对原油进行组分分离,结合界面张力测试结果和结构组成特征分析,进行原油不同组分与表面活性剂之间的界面活性研究。方法采用制备液相色谱技术对原油进行组分分离,考查原油及原油不同组分与阴离子表面活性剂磺酸盐和两性离子表面活性剂甜菜碱之间的界面张力变化趋势;采用气相色谱-质谱方法对原油不同组分的主要结构特征进行分析和对比。结果采用疏水型反相色谱填料,梯度洗脱方式,制备色谱可以将原油分离为6种结构组成差异较大的不同组分;以重烷基苯磺酸盐为表面活性剂时,不含芳烃的4种组分可产生超低界面张力(<1.0×10^(-3)mN/m),含少量芳烃的一种组分接近超低界面张力(~1.0×10^(-3)mN/m);以硫代甜菜碱-12为表面活性剂时,富含芳烃的一种组分可产生超低界面张力(<1.0×10^(-3)mN/m)。结论表面活性剂结构类型不同,产生超低界面张力对应的原油组分亦不同,原油组分与表面活性剂之间的界面活性关系较为复杂。

Objective To study the interfacial activity between crude oil components and surfactants,the crude oil components were separated,and their interfacial tension and characteristic structure composition were analyzed.Methods The crude oil components were separated by preparative liquid chromatography.The variation tendency of interfacial tension between different components of crude oil and anionic surfactant such as sulfonate,and zwitterionic surfactant such as betaine was investigated.The main structure characters of different crude oil components were analyzed and compared based on gas chromatography-mass spectrometry.Results Using hydrophobic reversed-phase chromatographic packing and mobile-phase gradient elution,crude oil can be separated into six different components with obvious differences of structure by preparative chromatography.When using the heavy alkylbenzene sulfonate as the surfactant,four components without aromatic hydrocarbon can obtain ultralow interfacial tension(<1.0×10^(-3)mN/m),one component with a small amount of aromatic hydrocarbon was close to ultralow interfacial tension(~1.0×10^(-3)mN/m).When using sulfobetaine 12(S-12)as the surfactant,one component rich in aromatic hydrocarbon can obtain ultralow interfacial tension(<1.0×10^(-3)mN/m).Conclusions The structure types of surfactants are different,and the crude oil components corresponding to ultra-low interfacial tension are also different.The interfacial activity relationship between crude oil components and surfactants is complicated.