石油羧酸盐与烷基苯磺酸盐的复配效果及其结构成因

Synergistic Effects of Petroleum Carboxylate/Alkyl Benzene Sulfonate Compound System and Its Structural Cause

黄宏度 陈思雅 秦少华 吴一慧 郑 为 陈 亮 陈友猛 张 群

HUANG Hongdu CHEN Siya QIN Shaohua WU Yihui ZHENG Wei CHEN Liang CHEN Youmeng ZHANG Qun

为揭示石油羧酸盐与烷基苯磺酸盐复配体系的性能特征，考察了石油羧酸盐和烷基苯磺酸盐形成的混合胶束（超分子结构）对复配体系界面活性的影响。结果表明，亲水亲油平衡值（HLB值）的差别使石油羧酸盐分子和烷基苯磺酸盐分子在油水界面上插入深度不同，由于距离拉开而减少了极性基团间的斥力，因而混合胶束排列得较紧密，界面吸附增加，界面活性比单剂好。此结构特点对复配体系界面活性的影响体现在：复配体系能在较宽的表面活性剂浓度及矿化度范围产生超低界面张力；在0.6%~1.2%弱碱（Na2CO3）下有优良的界面活性，避免了强碱（NaOH）对地层的伤害；达到超低界面张力所需表面活性剂浓度较低，可以降低驱油剂成本；在和油粒接触后可较快达到超低界面张力，对驱油过程有利。复配体系在强碱、弱碱、无碱情况下的界面活性均较好。和石油羧酸盐有良好协同效应的烷基苯磺酸盐应是直链分子结构，才能形成较紧密的混合胶束，具有较高的界面活性。图3参17

In order to reveal the performance of petroleum carboxylate and alkyl benzene sulfonate compound system, the effect of mixed micelle (supramolecular structure) formed from petroleum carboxylate and alkyl benzene sulfonate on the interfacial activity of compound system was investigated. The research results showed that the difference of hydrophilic lipophilic balance (HLB) value made petroleum carboxylate and alkyl benzene sulfonate having different insertion depth of molecules at oil-water interface. The distance of polar groups became far and polar group’s repulsion reduced. As a result, their mixed micelles arranged more closely, the interfacial adsorption increased and the interfacial activity was better than that of a single surfactant. The structural characteristics of compound system made it having the advantages of interfacial activity. Compound system had ultra-low interfacial tension in a wide range of surfactant concentration and salinity. It had an excellent interfacial activity in weak base case (0.6%—1.2% Na2CO3), which avoided formation damage from strong base (NaOH). It took less surfactant to achieve ultra-low interfacial tension and could reduce the cost of surfactants for chemical flooding. After contacting with oil droplet, it could quickly achieve ultra-low interfacial tension, which was beneficial to the oil displacement process. The interfacial activity of compound system was good in strong base, weak base and none-alkali system. The molecular structure of alkyl benzene sulfonate which had a good synergistic effect with petroleum carboxylate should be linear so that they could form closed mixed micelle with a better interfacial activity.