The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform

Seon-byeong Kim - One of the best experts on this subject based on the ideXlab platform.

  • The surface modification and characterization of SiO2 nanoparticles for higher Foam Stability.
    Scientific reports, 2020
    Co-Authors: Mansoo Choi, Chong-hun Jung, Wang-kyu Choi, Seon-byeong Kim
    Abstract:

    The surfactant and colloidal nanoparticles has been considered for various applications because of interaction of both complex mixtures. The hydrophilic SiO2 nanoparticle could not be surface active behavior at the liquid/air interface. In this study, the SiO2 nanoparticles have been modified with 3-isocyanatopropyltriethoxy-silane (ICP), and the effect of Foam Stability has been investigated. The physical properties of surface modified SiO2 nanoparticle were analyzed by XRD, TGA, FT-IR, and SEM. After surface modification of SiO2 nanoparticles, the contact angle of SiO2 nanoparticle was also increased from 62° to 82° with increased ICP concentration. The experimental result has shown that SiO2 nanoparticle with ICP was positive effect and improved Foam Stability could be obtained at proper ICP concentration compared with un-modified SiO2 nanoparticle.

Nima Shokri - One of the best experts on this subject based on the ideXlab platform.

  • Combined Effects of Nanoparticles and Surfactants upon Foam Stability
    Chemical Engineering Science, 2021
    Co-Authors: Mohammad Javad Shojaei, Paul Grassia, Yves Méheust, Abdulkadir Osman, Nima Shokri
    Abstract:

    We investigate effects of surfactants with different charges (anionic, cationic, and non-ionic) on Foam Stability in the presence of charge-stabilized silica (SiO2) 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 pre-requisite to Foam Stability analysis to test the compatibility between surfactants and nanoparticles.

  • Foam Stability in the presence and absence of hydrocarbons: From bubble- to bulk-scale
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2015
    Co-Authors: Kofi Osei-bonsu, Nima Shokri, Paul Grassia
    Abstract:

    One of the pioneering applications of Foam is in enhanced oil recovery (EOR). A major stumbling-block to the success of Foam application in EOR is the adverse influence of oil on Foam Stability. The objectives of the present work were to evaluate the effects of various surfactants and hydrocarbons with well-defined properties on Foam Stability. To do so, we have conducted a comprehensive series of experiments at bulk- and bubble-scale to investigate the Foam Stability of four surfactants in the absence and presence of three isoparaffins distinguished by their carbon chain length, density and viscosity. For the bulk Foam Stability experiments, Foam was generated by sparging pure air into surfactant solution in a vertical cylindrical column. An automated camera was used to record the gradual decay of Foam as a function of time. The results showed the significant impact of the type of the surfactant on Foam Stability. Besides, our results illustrated less stable Foam in the presence of oil with less adverse impact on Foam Stability as oil viscosity and density increased. The limitation of the method used in the present study to quantify Foam Stability, i.e., measuring the decay of Foam height over a certain period of time, which is a commonly used method in literature, is discussed here and an alternative approach is proposed to investigate Foam Stability at bubble-scale to supplement and improve understanding of the physical phenomena controlling Foam Stability.

David S. Schechter - One of the best experts on this subject based on the ideXlab platform.

  • The Synergy of Surfactant and Nanoparticles: Towards Enhancing Foam Stability
    Day 2 Mon October 14 2019, 2019
    Co-Authors: Zuhair Alyousef, David S. Schechter
    Abstract:

    Abstract Gas injection has been widely used for enhancing oil recovery in petroleum reservoirs. One of the major challenges facing this technique is the high mobility of gas caused by its lower viscosity compared to reservoir fluids. Injecting the gas in a Foam phase can solve the mobility challenge by increasing the gas apparent viscosity. Surface active agents such as surfactants are usually used to generate Foams. However, the long-term Stability of the surfactants is challenging. The synergistic effect of surfactants and nanoparticles may offer a novel technique to solve the Foam Stability issue and generate stronger Foams. This study evaluates the role of nanoparticles on stabilizing surfactant Foams in porous media. Anionic surfactant and surface modified silica nanoparticles were used in this assessment. Dynamic Foam tests were conducted to study the Foam Stability and strength in porous media. The major parameter used to evaluate the Foam strength in this study is the mobility reduction factor (MRF). The experiments were conducted using nitrogen gas at elevated pressure. The influence of nanoparticles on surfactant Foam strength was conducted at different nanoparticles concentrations and fixed surfactant concentration. The results demonstrated that the presence of nanoparticles in surfactant solution resulted in a more stable Foam compared to surfactant alone. The nanoparticles used in this study seem to enhance the Foam Stability by either one or two mechanisms: particle arrangement during film drainage or increasing the capillary pressure of coalescence. Based on the dynamic Foam tests, higher pressure drops were reported for the mixtures of nanoparticles and surfactant compared to surfactant alone. This clearly indicated the higher resistance to gas flow caused by the Foam generated using the mixture. The results also showed that as the nanoparticles concentration increased, MRF increased, too. The MRF for the sample contains only surfactant was 72. However, the addition of 0.50 and 1.00 wt% of nanoparticles to the surfactant solution resulted in higher MRF: 75 and 85, respectively. The need for generating strong Foam is very important to ensure the long term Stability of Foam and, consequently, reducing the gas mobility in porous media. The addition of solid nanoparticles to surfactant solutions might strengthen the aqueous film between gas bubbles and, eventually, enhancing the Foam Stability.

  • Enhancing the Foam Stability Using Surfactants Mixtures
    All Days, 2018
    Co-Authors: Mohammed A. Almobarky, Zuhair Alyousef, David S. Schechter
    Abstract:

    Abstract This work investigated experimentally the potential of the mixture of two anionic surfactants to reduce the mobility and enhance the oil recovery by generating stronger Foam than that of the individual surfactants. Foams of the Alcohol Alkoxy Sulfate (AAS), Internal Olefin Sulfonate (IOS) surfactants and their mixtures were compared in bulk and in porous media. In bulk, after the Foam has been generated by shaking, the Foam columns decay was monitored to measure the Foamability and Foam Stability. Furthermore, interfacial tension was measured for all surfactants solutions for explanation purposes and Foam Stability interpretations. Dynamically, Boise sandstone was used for surfactant-nitrogen co-injection for mobility reduction evaluation and Foam viscosity measurements. Finally, the enhanced oil recovery was investigated by conducting core-flooding experiments for Foam application after water flooding. AAS surfactant showed impressive Foamability in NaCl brines, but medium to poor Foam Stability especially with crude oil. On the other hand, IOS was the best in Deionized Water (DW) especially with crude oil, but poor Foamability in brine. The synergism was more obvious in brine than in DW. For instance, the mixture provided five times and four times longer Foam half-lives than AAS in absence and presence of crude oil, respectively. Dynamically, the Foam generation was observed by the pressure drop jump during the surfactant-gas co-injection. The mixture reduced the mobility 13 and 5 times in comparison with that of AAS. Finally, the application of Foam flooding as a tertiary recovery process resulted in 7.5% additional oil recovery by the mixture compared with 2.5% for AAS.

  • The effect of nanoparticle aggregation on surfactant Foam Stability.
    Journal of colloid and interface science, 2017
    Co-Authors: Zuhair Alyousef, Mohammed A. Almobarky, David S. Schechter
    Abstract:

    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.

Saeed Farrokhpay - One of the best experts on this subject based on the ideXlab platform.

  • Effects of surface rheology and surface potential on Foam Stability
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2016
    Co-Authors: Jianlong Wang, Anh V. Nguyen, Saeed Farrokhpay
    Abstract:

    Here, we examine the collapse of standing aqueous Foams stabilized by the anionic surfactant SDS, using DOH and sodium chloride (NaCl) respectively to produce different surface viscoelasticities and surface potentials in order to elucidate the roles of surface rheology and intermolecular forces in Foam Stability. Inspired from chemical kinetics, we proposed a model to quantify the Foam collapse process and to compare the Foam Stability with two characteristic parameters: the Foam half-life, tau, and the prefactor of Foam collapse rate, n/tau. The presence of DOH in the SDS solutions can significantly increase the surface viscoelasticity and Foam Stability, despite the decreased surface potential caused by the displacement of SDS molecules by DOH molecules at the air-water interface. The correlation between surface viscoelasticity and Foam Stability is explained by the decrease in Foam drainage and the increased liquid film Stability. For SDS-NaC1 mixtures with the same value of the mean ionic product (1 mM), an increased concentration of NaC1 in the SDS solution reduces the surface potential and the Debye length because of the screening effect resulting from the binding of sodium counter ions to the sulfate head groups. The Foam Stability decreases because of the weakened repulsive interactions between the two interfaces of the liquid films, despite the presence of the same surface concentration of SDS molecules, as indicated by the same equilibrium surface tension. This paper highlights two different mechanisms that dominate Foam Stability. (C) 2015 Elsevier B.V. All rights reserved.

Klaus Lunkenheimer - One of the best experts on this subject based on the ideXlab platform.

  • Relationship between surface dilational properties and Foam Stability.
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2000
    Co-Authors: H. Fruhner, Klaus-dieter Wantke, Klaus Lunkenheimer
    Abstract:

    Abstract The knowledge of the Stability of Foams and emulsions is very important for the control of a large number of technological processes. However, in spite of much intense research, the mechanism of Foam Stability is still not completely clear. Foam Stability depends on many parameters but the type of the added surfactant and the surface rheological properties of the adsorption layers play the most important role. Because of the lack of reliable surface rheological data a comprehensive investigation of this problem was not yet possible. However, we can now present measurements of surface dilational properties of soluble adsorption layers in a frequency range of 1–500 Hz using a new version of the oscillating bubble method. The results are compared with measurements of Foam Stability. This indicates that the surface dilational viscosity plays an important role in the Stability of Foam films. A direct relation between surface dilational elasticity values and Foam Stability could not be detected for the examined systems. Pure elastic adsorption layers were not able to stabilize Foam lamellas.