表面活性剂/盐/油酸甲酯模拟油体系协同效应机理研究

Synergism of the model oil system of surfactant/ brine/methyl oleate

从油相性质和水相性质对具有一定亲水-亲油能力的表面活性剂在油水界面上吸附的影响出发,研究模拟油中的有机添加剂(有机酸、长链醇)和不同结构的原油酸性活性组分与外加表面活性剂之间以及不同亲水、亲油能力的二元混合表面活性剂之间在降低界面张力方面的协同效应。油相中的油酸甲酯通过改变外加表面活性剂在油、水相之间的分配而影响界面浓度,从而影响界面张力,随着油相中油酸甲酯浓度的增加,油相中有机活性物质与不同结构的外加表面活性剂之间的协同效应有正有负,协同效应是正还是负与具体的水相性质密切相关。提出了判别表面活性剂与模拟油中有机物降低界面张力方面协同效应正负的经验方法,用该经验方法得出的结果与实验结果完全一致。

The synergism for lowering interfacial tension between surfactant molecules and organic additives in model oil, such as car-boxylic acids, octadecanol and surface-active fractions in crude oil had been studied based on the influence of oil phase and aqueous phase on the interfacial adsorption of surfactants with hydrophilic-lipophilic ability. The methyl oleate in oil phase influenced the interfacial surfactant concentration and interfacial tension by changing the distribution of added surfactant in oil phase and aqueous phase. Synergism/antagonism between added surfactants with different structure and organic surface-active components in oil phase can be observed with increasing methyl oleate concentration in oil phase, which is in close relationship with aqueous phase. The empirical equation, which can judge synergism or antagonism, had also been provided. The results obtained from empirical equation were in very good agreement with the experimental data.