阴离子双子表面活性剂的油水界面张力研究

为探究GA系列新型阴离子双子表面活性剂的油水界面活性及提高油层原油采收率的可行性,以模拟地层水和东河塘稀油,在45℃条件下,利用旋转液滴法测试了不同分子结构阴离子双子表面活性剂与稀油间的界面张力,并以GA12-4-12为对象,测试了其在不同浓度时的动态界面张力,考察了其与非离子表面活性剂ANT的复配性能。结果表明:连接基长度及碳链长度越长,油水界面张力越低;随GA12-4-12浓度增加,界面张力先降后升,0.3%时油水界面张力仅0.00885mN/m,但时间稳定性变差;GA12-4-12与ANT复配协同效果明显,复配比为4∶1时0.1%(GA12-4-12+ANT)加量可使油水界面张力达超低(0.00884mN/m),明显降低了GA12-4-12用量。可见GA12-4-12与ANT复配体系具有低剂量下提高原油采收率的性能,建议用该配方进行提高原油水驱采收率试验研究工作。

Study on oil-water interfacial tension of anionic gemini surfactant

In order to probe the oil-water interfacial activity and feasibility of enhancing oil recovery by a new-type Anionic Gemini surfactant (GA series). The experiment was conducted under the circumstance of simulated formation water and Donghetang thin oil at the temperature of 45 ℃. Interfacial tension between Anionic Gemini surfactant with different structures and thin oil were tested through “rotating drop method”. By taking GA12-4-12 as an object, its dynamic interfacial tension in different concentrations was recorded. Also, the blending performance with nonionic surfactant ANT was explored. Results showed that the longer length of linking group is and carbon chain, the lower is interfacial tension between Gemini surfactants solution and oil. As GA12-4-12 concentration increased, the interfacial tension first decreased to a certain point and then increased. Water-oil interfacial tension of 0.3% of GA12-4-12 was only 0.00885 mN/m while the time stability got worse. The synergetic efficiency of GA12-4-12 /ANT mixed system was obvious. When ratio came to 4∶1, concentration of (GA12-4-12+ANT) was 0.1% and water-oil interfacial tension dropped to ultralow (0.00884 mN/m), which obviously reduced the amount of GA12-4-12. It can be seen that GA12-4-12 /ANT mixed system has the possibility to enhance oil recovery in a low amount. It is recommended to make experimental research on water flooding recovery of this formula.