阴阳离子表面活性剂体系超低油水界面张力的应用

Application of Anion-Cation Pair Surfactant Systems to Achieve Ultra-Low Oil-Water Interfacial Tension

通过阴阳离子表面活性剂复配,在实际油水体系中获得了超低界面张力.通过在阴离子表面活性剂分子结构中加入乙氧基(EO)链段,以及采用阴阳离子加非离子型表面活性剂的三组分策略,有效解决了混合表面活性剂在水溶液中溶解度问题.进而研究了阳离子表面活性剂结构、非离子表面活性剂结构、三者组分配比、表面活性剂总浓度等因素对油水界面张力的影响,从而在胜利油田多个实际油水体系中获得了较大比例范围和较低浓度区域的油水超低界面张力,部分体系甚至达到了10-4mN·m-1.由于阴阳离子表面活性剂间强烈的静电吸引作用,相关体系具有很好的抗吸附能力.经过石英砂48h吸附后,体系仍然具有很好的超低界面张力.

In this paper,ultra-low interfacial tension was obtained in realistic oil-water systems using ion pair surfactant systems.To improve the solubility of the ion pair surfactants,polyoxyethylene chain was introduced into the anionic surfactant molecular structure,and a three-component strategy where ion pair surfactants were combined with a non-ionic surfactant was used.Furthermore,the effects of the structures of the cationic and non-ionic surfactants,distribution ratio of the three components,and surfactant concentration on oil-water interfacial tension were studied.We successfully achieved the ultra-low interfacial tension in the Shengli oil fields using the mixed systems combining ion pairs and non-ionic agents.Several systems possessed an interfacial tension as low as 10-4 mN·m-1.Because of the strong electrostatic attraction between surfactant ions,our systems possess ultra-low interfacial tension after adsorption.The results show that after 48 h quartz adsorption,the systems can still reduce the interfacial tension to an ultra-low level.