大庆原油酸性组分界面膜扩张流变研究

Dilational Rheological Study of Interfacial Film Containing Acidic Components from Daqing Crude Oil

采取醇碱液萃取法从大庆原油中分离得到酸性组分,通过滴外形分析方法研究了酸性组分模拟油的界面张力和扩张流变性质,考察了振荡频率和酸性组分质量分数的影响。结果表明,大庆酸性组分具有较强的界面吸附能力,能大大降低油水界面张力,其扩张流变行为与表面活性剂类似:扩张模量均随振荡频率增大而增大,随体相质量分数的增加通过一个极大值;相角则随扩张频率降低而增大,同时随体相质量分数增加而单调增大。与文献报道相比,大庆酸性组分扩张模量的最大值在45mN/m左右,远高于胜利原油酸性组分。

The acidic components were extracted from Daqing crude oil by using NaOH/EtOH mixed solution.The interfacial tension and dilational rheological properties were investigated at the kerosene-water interface by means of oscillating drop method.The effects of oscillating frequency and bulk mass fraction on interfacial dilational properties were exploited.The results show that the acidic component molecules can easily adsorb onto the interface and greatly reduce interfacial tension.The interfacial dilational behaviors of acidic components are similar to those of surfactants.The modulus increased with increasing frequency and passed through a maximum with bulk concentration increasing,while phase angle increased with decreasing frequency or increasing concentration monotonically.Morover,the modulus maximum of Daqing acidic components is about 45 mN/m,which is much higher than that of Shengli acidic components.