Surface behavior of hydrophilic silica nanoparticle-SDS surfactant solutions: I. Effect of nanoparticle concentration on foamability and foam stability (original) (raw)
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Experimental Study of SDS Foam Stability in the Presence of Silica Nanoparticle
Journal of Chemical and Petroleum Engineering, 2022
In this study, the effect of silica nanoparticles on the stability of foams that are stabilized with sodium dodecyl sulfate anionic surfactant was investigated. This surfactant can significantly increase the stability of the foam by reducing the surface tension. For experiments, first, the stability of the foam obtained from this surfactant in the presence of deionized water and then in the presence of NaCl solution and seawater were investigated. Then, by changing the salinity of NaCl solution and seawater, a change in the stability of the resulting foams was investigated, and the results were reported. The effect of the simultaneous presence of different concentrations of silica nanoparticles in the above solutions was investigated, and stability results were reported. According to the experimental results, the amount of foaming and the half-life of foam in the presence of deionized water is equal to 201 minutes, but the addition of brine reduces this amount. The presence of nanoparticles increases stability. In the presence of deionized water and surfactant, it reaches more than 280 minutes. Finally, the surface tension changes in the optimal concentration of the surfactant in exchange for the change in the concentration of nanoparticles were investigated. In the optimal concentration of surfactant and NaCl solution, the surface tension decreased to 21 mN/m.
Combined effects of nanoparticles and surfactants upon foam stability
We investigate effects of surfactants with different charges (anionic, cationic, and non-ionic) on foam stability in the presence of charge-stabilized silica (SiO 2) nanoparticles. Toward this aim, a comprehensive series of experiments on a Hele-Shaw cell and a foam column is conducted at bubble and bulk-scale respectively, that is, investigating phenomenologies of foam coarsening separately by gas diffusion and bubble coalescence, and by gravitational drainage. Our results show nanoparticles, despite their ability to position themselves at liquid-gas interfaces and thus limit the resulting surface tension coefficient, do not necessarily have a positive effect on foam stability; the nature and magnitude of this effect depends strongly on the nature of the surfactant, its concentration and the concentration of nanoparticles. In less stable systems, significant coarsening occurs. Both results from bubble-scale and the bulk-scale experiments suggest that compatibility experiments are prerequisite to foam stability analysis to test the compatibility between surfactants and nanoparticles.
The effect of nanoparticle aggregation on surfactant foam stability
Journal of Colloid and Interface Science, 2017
The combination of nanoparticles (NPs) and surfactant may offer a novel technique of generating stronger foams for gas mobility control. This study evaluates the potential of silica NPs to enhance the foam stability of three nonionic surfactants. Results showed that the concentration of surfactant and NPs is a crucial parameter for foam stability and that there is certain concentrations for strong foam generation. A balance in concentration between the nonionic surfactants and the NPs can enhance the foam stability as a result of forming flocs in solutions. At fixed surfactant concentration, the addition of NPs at low to intermediate concentrations can produce a more stable foam compared to the surfactant. The production of small population of flocs as a result of mixing the surfactant and NPs can enhance the foam stability by providing a barrier between the gas bubbles and delaying the coalescence of bubbles. Moreover, these flocs can increase the solution viscosity and, therefore, slow the drainage rate of thin aqueous film (lamellae). The measurements of foam half-life, bubble size, and mobility tests confirmed this conclusion. However, the addition of more solid particles or surfactant might have a negative impact on foam stability and reduce the maximum capillary pressure of coalescence as a result of forming extensive aggregates.
Bulk and bubble-scale experimental studies of influence of nanoparticles on foam stability
Chinese Journal of Chemical Engineering, 2017
Influence of silicon oxide (SiO 2) and aluminum oxide (Al 2 O 3) nanoparticles on stability of nanoparticles and sodium dodecyl sulfate (SDS) mixed solutions foams were studied at bulk and bubble-scale. Foam apparent viscosity was also determined in Hele-Shaw cell In order to investigate the foam performance at static and dynamic conditions. Results show that the maximum adsorption of surfactant on the nanoparticles occurs at 3 wt% surfactant concentration. Foam stability increases while the foamability decreases with the increasing nanoparticles concentration. However, optimum nanoparticles concentration corresponding to maximum foam stability was obtained at 1.0 wt % nanoparticles concentration for the hydrophilic SiO 2 /SDS and Al 2 O 3 /SDS foams. Foam performance was enhanced with increasing nanoparticles hydrophobicity. Air-foams were generally more stable than CO 2 foams. Foam apparent viscosity increased in presence of nanoparticles from 20.34cp to 84.84cp while the film thickness increased from 27.5 µm to 136 µm. This study suggests that the static and dynamic stability of conventional foams could be improved with addition of appropriate concentration of nanoparticles into the surfactant solution. The nanoparticles improve foam stability by their adsorption and aggregation at the foam lamellae to increase film thickness and dilational viscoelasticity. This prevents liquid drainage and film thinning and improves foam stability both at the bulk and bubble scale.
Interaction between Surfactants and SiO2 Nanoparticles in Multiphase Foam and Its Plugging Ability
Energy & Fuels, 2017
To improve the stability of foam fluids, SiO 2 nanoparticles and trace amount of Gemini cationic surfactant were combined with the main foaming agent, nonionic surfactant, to form a tricomponent multiphase foam. The stability of the multiphase foam was assessed through two parameters of half-life time and dilational modulus. The interaction between surfactants and nanoparticles were studied though surface tension, adsorption amount, and ζ potential measurement. The effects of saline ions and temperature on foam stability were also investigated. The plugging ability of the tricomponent multiphase foam was assessed using a sandpack model. The optimized tricomponent multiphase foam was 10 times more stable than corresponding foam without nanoparticles in terms of half-life time and also resisted to saline and temperature to a certain degree because the adsorption of nanoparticles at the interface improved the mechanic strength of foam film. The tricomponent multiphase foam showed more excellent plugging ability in porous media than foam without nanoparticles during flooding. The adsorption of cationic surfactant not only changed the surface hydrophobicity of the SiO 2 nanoparticles, but also promoted the adsorption of APG molecules. Combined the results of Gemini C 12 C 3 C 12 Br 2 replaced by CTAB or SDS, and C 12 C 3 C 12 Br 2 /SiO 2 replaced by pretreated partially hydrophobic SiO 2 nanoparticle (H15), it is deduced that the in situ surface modification by cationic adsorption to a suitable hydrophobicity was a key step in multiphase stability. Compared with the pretreated partially hydrophobic SiO 2 nanoparticle, more SiO 2 nanoparticles were distributed at the air/liquid interface and utilized effectively in the tricomponent multiphase foam.
Soft Matter, 2008
We have performed a quantitative study of the coarsening of foams stabilised by partially hydrophobic silica nanoparticles. We have used a variety of techniques: optical and electron microscopy, microfluidics, and multiple light scattering. Using earlier studies of planar particle monolayers, we have been able to correlate the interfacial properties and the macroscopic temporal evolution of the foam. This has shed light on the origin of the absence of coarsening of particle-stabilised foams. Such particlestabilised foams appear to be the only known foam system where coarsening is inhibited by surface elasticity.
Journal of Dispersion Science and Technology, 2017
The properties of aqueous foams stabilized by a mixture of negatively-charged silica nanoparticles and hexadecyltrimethylammonium bromide were studied in this work. Rheological properties of the foams were studied. The interaction between nanoparticles and surfactant molecules in the bulk phase was studied by zeta potential and size measurements of the particles. The interaction at the interface was studied by means of interfacial shear rheology, surface pressure measurement, and atomic force microscopy. It was found that foams were more stable at low surfactant concentrations, though the foamability was low. This was due to the formation of a strong viscoelastic film of surfactant-laden particles at the air-water interface. A suitable mechanism has been proposed to explain the stability of foams in the presence of nanoparticles at different surfactant concentrations.
Investigation of Static Foam Behavior Using Nanoparticles
Static foam behavior of the surfactant in the presence and absence of nanoparticles (NPs) were investigated. The role of TiO 2 and SiO 2 NPs for percentage foamability and foam stability of surfactants (SLS, Tween-80 & CTAB) were studied and checked the effects of temperature, pH, NPs and methanol on foam behavior. The stability of foam was determined by measuring the half-life (t 1/2) time. Foam stability was more in presence of TiO 2 and SiO 2 NPs.