Groenendijk Dirk J, van Wunnik Johannes N M
Shell Global Solutions International B.V., Amsterdam, Grasweg 31, 1031 HW Amsterdam, The Netherlands.
ACS Omega. 2021 Jan 11;6(3):2248-2254. doi: 10.1021/acsomega.0c05532. eCollection 2021 Jan 26.
The monomer-micelle equilibrium is shown to be responsible for an asymmetry between surfactant adsorption and desorption rates. When a solution containing micelles is brought into contact with a solid surface, the micelles dissociate to supply monomers that adsorb to the surface. When the same surface is subsequently exposed to a surfactant-free solution, desorption occurs slowly because of the higher affinity of the monomers to remain to the surface than to form micelles. As a result, the number of monomers that desorb is limited by the critical micelle concentration (CMC) of the surfactant. This effect is particularly pronounced for surfactants with low CMC values and in systems with high surface-to-volume ratios, such as porous media. A generic model is developed and applied to simulate the Ca-mediated adsorption and desorption of surfactants in limestone cores.
单体 - 胶束平衡被证明是表面活性剂吸附和解吸速率不对称的原因。当含有胶束的溶液与固体表面接触时，胶束解离以提供吸附到表面的单体。当同一表面随后暴露于无表面活性剂的溶液中时，由于单体与表面结合的亲和力高于形成胶束的亲和力，解吸过程缓慢。因此，解吸的单体数量受到表面活性剂临界胶束浓度（CMC）的限制。对于具有低CMC值的表面活性剂以及在具有高表面积与体积比的系统（如多孔介质）中，这种效应尤为明显。开发了一个通用模型并应用于模拟石灰岩岩心中钙介导的表面活性剂吸附和解吸。
