Effect of surfactant headgroups on the oil/water interface: An interfacial tension measurement and simulation study

Xu, Jiafang; Zhang, Yang; Chen, Haixiang; Wang, Pan; Xie, Zhenhua; Yao, Yongji; Yan, Youguo; Zhang, Jun

doi:10.1016/j.molstruc.2013.07.049

Cited by 150 publications

(81 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Polymer solutions were not considered in this study because the equipment used in this research is designed only for fluids with very low interfacial tension. Interfacial tension results were similar to other studies [51][52][53][54][55] in advanced oil recovery tests. Table 2 presents the porous volume (PV) of the sandstone cores used in EOR experiments and shows the results for oil initial saturation (S oi ), oil residual saturation after the use of brine (S or_b ) and after the use of nanoemulsions (S or_n ), and oil displacement efficiency in conventional (E dc ), enhanced (E dn ), and total (E dT ) stages.…”

Section: Lonano Characterizationsupporting

confidence: 89%

Experimental Study of Nanofluids Applied in EOR Processes

Dantas

Souza

Neto

et al. 2017

J Surfact & Detergents

View full text Add to dashboard Cite

Nanoemulsions are small droplet‐sized systems that have low surface tension and a small percentage of active material in their composition. In this study, low oil content nanoemulsion systems were developed for the use in enhanced oil recovery (EOR). The experiments were performed on a device capable of simulating petroleum reservoir conditions using sandstone rock cores. Nanoemulsions were obtained from a pre‐selected microemulsion system composed of: RNX95 as surfactant, isopropyl alcohol as cosurfactant, kerosene as oil phase, and distilled water as aqueous phase. Different percentages of polyacrylamide were added to the systems obtained to evaluate the influence of viscosity in EOR results. The nanoemulsion droplet sizes ranged from 9.22 to 14.8 nm. Surface tension values were in the range of 33.6–39.7 dyn/cm. A nanoemulsion system with 2.5 wt% surfactant was used in EOR assays. The oil recovery was directly proportional to polymer percentage in the nanoemulsion, ranging from 39.6 to 76.8%. The total oil in the place recovery ranged from 74.5 to 90%.

show abstract

Section: Lonano Characterizationsupporting

confidence: 89%

Experimental Study of Nanofluids Applied in EOR Processes

Dantas

Souza

Neto

et al. 2017

J Surfact & Detergents

View full text Add to dashboard Cite

show abstract

“…A common method for defining the interfacial thickness is the “90–90” criterion (Jang et al, ; Xu et al, ), which defines the oil–water interfacial thickness t total as the distance between two positions where the densities of dodecane and water are 90% of their own bulk densities. In addition, the thickness between the interfacial oil t oil and interfacial water t water is defined as the distance between two positions where the density varies from 10% to 90% of their bulk phase densities (Jang et al, ; Rivera et al, , ; Xu et al, ).…”

Section: Resultsmentioning

confidence: 99%

“…A common method for defining the interfacial thickness is the "90-90" criterion (Jang et al, 2004;Xu et al, 2013), which defines the oil-water interfacial thickness t total as the distance between two positions where the densities of dodecane and water are 90% of their own bulk densities. In addition, the thickness between the interfacial oil t oil and interfacial water t water is defined as the distance between two positions where the density varies from 10% to 90% of their bulk phase densities (Jang et al, 2004;Rivera et al, 2002Rivera et al, , 2003Xu et al, 2013). The results of the interfacial thickness analysis are summarized in Table 2, wherein the thickness of components t oil and t water increased following the addition of a surfactant due to the penetration of the hydrophobic alkyl tails and hydrophilic polar groups into dodecane and water, respectively.…”

Section: Interfacial Thicknessmentioning

confidence: 99%

Effects of Surfactant Headgroups on Oil‐in‐Water Emulsion Droplet Formation: An Experimental and Simulation Study

Zhang

Liu

et al. 2018

J Surfact & Detergents

View full text Add to dashboard Cite

Nonpolar oils such as kerosene and diesel oil are common collectors in coal flotation. Surfactants are usually added to the pulp to emulsify the oil collectors. The present study used dodecane as the oil collector and anionic sodium dodecyl sulfonate (SDS) and nonionic tetraethylene glycol monododecyl ether (C12EO) with different headgroups and identical chain alkyls to investigate the effect of the surfactant headgroups on oil‐in‐water emulsion droplet formation. The morphology and stability of dodecane emulsions were determined experimentally. Density functional theory (DFT) and molecular dynamics (MD) simulations were used to explain the microscopic mechanism. The results of DFT indicated a larger interaction between SDS and the water molecules than that between C12EO and water molecules. The results obtained by MD suggested that the SDS headgroup exhibited a loose arrangement and a relatively large gap size, thereby weakening the interaction between SDS and water molecules at the dodecane/water interface. In contrast, the headgroups of C12EO were bent and interwoven with others to form a tight reticulation at the interface. According to the simulation results, the ability of the surfactant to form dodecane‐in‐water emulsion droplets depends on the arrangement of the surfactants at the oil–water interface rather than on the interaction strength between the headgroups of the surfactants and water molecules. The presented microscopic mechanism of the surfactant headgroup formation of oil‐in‐water emulsion droplets offers surfactant selection and design references.

show abstract

“…[86,[92][93][94][95], the MD method was used for the assessment of surface tension and CMC of different amphiphiles. Modeling of the ethanol behavior, done by Tarek et al [86], gives the adequate orientation of the alcohol molecule at the interface with the hydrophilic part in the water phase and the hydrophobic in the air.…”

Section: Molecular Mechanicsmentioning

confidence: 99%

“…Xu et al [95] examined the impact of the hydrophilic parts of ionic surfactants on the interfacial tension. Modeling was performed in the framework of quantum mechanics and molecular dynamics.…”

Section: Molecular Mechanicsmentioning

confidence: 99%

Theoretical description of 2D-cluster formation of nonionic surfactants at the air/water interface

2015

View full text Add to dashboard Cite

Recent progress in modeling of the surfactant behavior from atomistic to continuous at the air/water interface across different space-time scales is reviewed. Advantages and disadvantages of modern quantum mechanical, molecular dynamical, and mesoscale methods are discussed for description of interactions between amphiphilic molecules leading to formation of 2D films. The use of nonempirical and semiempirical methods for assessment of the thermodynamic and structural parameters of large van der Waals complexes is of particular interest. An approach for calculation of the thermodynamic and structural parameters of clusterization for nonionic surfactants at the air/water interface is proposed on the basis of the quantum chemical semiempirical PM3 method. This approach implicitly takes into account the influence of the interface on the surfactant molecules via stretching and orienting effect. The calculations are carried out in the supermolecule approximation for a limited number of small amphiphilic aggregates with different alkyl chain. The correlation analysis of the calculated data array provides the increments contributing by the intermolecular CH···HC interactions and interactions between hydrophilic parts into the thermodynamic parameters of formation and clusterization. Obtained increments are further used for constructing the dependencies of the thermodynamic clusterization parameters per one monomer on the alkyl chain length for large clusters up to 2D films. In the framework of the proposed theoretical approach, the next parameters are calculated as follows: enthalpy, entropy, and Gibbs' energy of clusterization for 11 homologous series of nonionic surfactants, threshold chain length enabling the process of monolayer formation at standard conditions, the Btemperature effect^of clusterization, and the structural parameters of the monolayer unit cell (particularly the tilt angle) depending on the size of the hydrophilic headgroup of the amphiphilic compound.

show abstract

Effect of surfactant headgroups on the oil/water interface: An interfacial tension measurement and simulation study

Cited by 150 publications

References 46 publications

Experimental Study of Nanofluids Applied in EOR Processes

Experimental Study of Nanofluids Applied in EOR Processes

Effects of Surfactant Headgroups on Oil‐in‐Water Emulsion Droplet Formation: An Experimental and Simulation Study

Theoretical description of 2D-cluster formation of nonionic surfactants at the air/water interface

Contact Info

Product

Resources

About