Abstract: A series of cationic functional polymers with different cations and molecular weights were used to determine the oil water interfacial tension, Zeta potential and O/W emulsion stability of the oil and water of the Gudong crude oil. It was found that when the molecular weight was almost the same, the bigger of the cationic degree, the better ability of breaking the O/W emulsions by the polymers . And in the region of the investigated concentration, at higher concentration of the polymer, better demulsification effects were obtained. The results of interfacial tension and zeta potential measurements indicated that the reason of the demulsification of emulsion by this kind of cationic functional polymer was the electrical neutralization on the interface between oil and water. That is to say, when polymer was added to the emulsion, it could neutralize the charges on the interface and as a result the oil droplets coalescenced.

Key words: Gudong crude oil, Functional polymer, Emulsion, Interfacial tensiton, Demulsification

摘要： 选用了一系列具有不同阳离子度和分子质量的阳离子功能性聚合物,分别测定了其与孤东原油模拟油的油水界面张力、Zeta电位、O/W 型乳状液的稳定性。研究发现,当阳离子功能性聚合物的分子质量相近时,阳离子度越大,其对O/W 型乳状液的破乳效果越好;在所研究质量浓度范围内,阳离子功能性聚合物质量浓度较高时, 其破乳效果较好。油水界面张力和Zeta电位结果显示,阳离子功能性聚合物对O/W 乳状液的破乳机理为界面电中和机理。加入阳离子聚合物后,能中和油珠表面电荷,促使油珠聚结,且高分子聚合物有“桥联”作用,加快油珠聚结, 从而实现O/W 乳状液的破乳。

关键词: 孤东原油, 功能性聚合物, 乳状液, 界面张力, 破乳