Adsorption of Zwitterionic Surfactant on Limestone Measured with High-Performance Liquid Chromatography: Micelle–Vesicle Influence

Abstract

Herein is presented a new methodology to determine the static adsorption of a zwitterionic surfactant on limestone in three different aqueous media [high-performance liquid chromatography (HPLC) water, seawater, and connate water] with the use of HPLC at room temperature and 70 °C. The results showed that, in both HPLC water and seawater, the surfactant adsorption followed a monolayer Langmuir tendency. In contrast, for connate water, the surfactant presented a new adsorption profile, characterized by two regions: (i) At surfactant concentrations below 1500 mg L(-1), an increase of adsorption is observed as the amount of divalent cations increases in the aqueous media. (ii) At surfactant concentrations above 1500 mg L(-1), the adsorption decreases because the equilibrium, monomer ⇆ micelle ⇆ vesicle, is shifted to the formation of vesicles, giving as a result a decrease in the concentration of monomers, thus reducing the interaction between the surfactant and the rock, and therefore, lower adsorption values were obtained. The behavior of the surfactant adsorption under different concentrations of divalent cations was well-described by the use of a new modified Langmuir model: (dΓ/dt)ads = k(ads)c(Γ∞ - Γ) - k(cmc)(c - c(cmc))(n)ΓH(c - c(cmc)). It was also observed that, as the temperature increases, the adsorption is reduced because of the exothermic nature of the adsorption processes.

Adsorption behavior of dodecyl hydroxypropyl sulfobetaine on limestone in high salinity water

“…It could be found that, with the increase of NaCl concentration, equilibrium adsorption of DSB on limestone decreased. Our ndings were opposite to the results of Nieto-Alvarez et al 15 In the study of Nieto-Alvarez et al 15 with the increase of water salinity, equilibrium adsorption increased. Cocamidoproyl hydroxysultaine (in the study of Nieto-Alvarez et al) has a similar structure and property to DSB used in our study.…”

“…meant that a small amount of inorganic salt could favor the formation of vesicles, while further addition of inorganic salt would inhibit the formation. In Nieto-Alvarez et al's study, 15 the results showed that formation of vesicles was responsible for the decrease of adsorption at high surfactant concentrations. Different from Nieto-Alvarez et al's study, the formation of vesicles occurred at low inorganic salt, so no adsorption decrease was detected in our study.…”

“…8, it could be found that, with increasing temperature, adsorption of DSB on limestone increased slightly. Because of the exothermic nature of most of the interactions of this type, 15 the adsorption decreases as the temperature is increased. So our results looks a paradox.…”

Controlled delivery and release of surfactant for enhanced oil recovery by nanodroplets

“…A Thermo Acclaim surfactant plus HPLC column (Thames Restek Ltd., UK) of dimensions 3 mm×150 mm and particle size of 5 m was used in this study. This type of column is compatible with aqueous and organic phases and is appropriate for the analysis of a wide variety of surfactant types at high salinity [32][33][34]. HPLC measurements were performed in an Agilent 1290 Infinity UHPLC.…”

Characterizing adsorption of associating surfactants on carbonates surfaces

“…Here, an optimized HPLC-ELSD [22][23][24][25][26] method was successfully developed for the analysis of complex multicomponent surfactant formulations that cannot be analyzed by conventional titration methods due to their interactions. Second, the adsorption of each component and surfactant blend was systematically studied on differently charged mineral surfaces.…”