Oil-laden (OL) foams could serve an important role in various processes, particularly in enhanced oil recovery; however, OL foams are less studied than aqueous foams. In this work, the formation and stability of OL foam, by either sodium dodecyl sulphate (SDS) or Triton X-100 (TX-100) in water-pentane mixture, was evaluated. We first constructed a diagram of good and poor foaminess against pentane content in the mixture and aqueous surfactant concentration. It was shown that surfactant onset concentration for good foaming was increased with increasing pentane content. The result was fitted using a mathematical model that considers the surfactant dilution and adsorption effects by pentane. Foam height decay profiles were also monitored. Results indicated that SDS resulted in a more stable foam than TX-100 at the same critical micelle concentration (CMC). Depending on surfactant concentration, OL foams exhibited strikingly different stability behaviours. Pentane acted as an anti-foamer at surfactant concentrations at the CMC or lower. However, very high foam stability was displayed at high surfactant concentration (e.g., 3× CMC) and medium to high pentane contents; this is a result contradictory to the predication of entering, spreading, and bridging coefficients in the classic theory. The stable OL foams of this study could be attractive to potential foam applications.

中文翻译：

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含油泡沫的形成和稳定性：表面活性剂和烃类溶剂的影响

含油 (OL) 泡沫可在各种工艺中发挥重要作用，尤其是在提高石油采收率方面；然而，与水性泡沫相比，OL 泡沫的研究较少。在这项工作中，通过十二烷基硫酸钠 (SDS) 或 Triton X-100 (TX-100) 在水 - 戊烷混合物中评估了 OL 泡沫的形成和稳定性。我们首先构建了一个关于混合物中戊烷含量和含水表面活性剂浓度的好和差泡沫的图表。结果表明，良好发泡的表面活性剂起始浓度随着戊烷含量的增加而增加。结果使用数学模型拟合，该模型考虑了戊烷对表面活性剂的稀释和吸附作用。还监测了泡沫高度衰减曲线。结果表明，在相同的临界胶束浓度 (CMC) 下，SDS 产生比 TX-100 更稳定的泡沫。根据表面活性剂浓度的不同，OL 泡沫表现出截然不同的稳定性行为。戊烷在表面活性剂浓度为 CMC 或更低时充当消泡剂。然而，在高表面活性剂浓度（例如，3×CMC）和中至高戊烷含量下显示出非常高的泡沫稳定性；这是一个与经典理论中的进入、传播和桥接系数的预测相矛盾的结果。本研究的稳定 OL 泡沫可能对潜在的泡沫应用具有吸引力。在高表面活性剂浓度（例如，3×CMC）和中至高戊烷含量下显示出非常高的泡沫稳定性；这是一个与经典理论中的进入、传播和桥接系数的预测相矛盾的结果。本研究的稳定 OL 泡沫可能对潜在的泡沫应用具有吸引力。在高表面活性剂浓度（例如，3×CMC）和中至高戊烷含量下显示出非常高的泡沫稳定性；这是一个与经典理论中的进入、传播和桥接系数的预测相矛盾的结果。本研究的稳定 OL 泡沫可能对潜在的泡沫应用具有吸引力。