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Bu-yao Zhu - One of the best experts on this subject based on the ideXlab platform.

  • Surfactant Adsorption at solid-liquid interfaces
    Advances in Colloid and Interface Science, 1991
    Co-Authors: Bu-yao Zhu
    Abstract:

    Abstract The purpose of this review is to introduce systematically a new Adsorption theory which is particularly applicable to Surfactant Adsorption, but might also be useful in other cases. The Adsorption of Surfactant from solution onto solids generally shows two-step character. In the first step the surface-active species are adsorbed through the interactions (i.e. electrostatic interaction and/or van der Waals interaction) between surface-active species and the solid interface. In the second step the Surfactants are adsorbed through the interaction (i.e. hydrophobic interaction if the Adsorption is from aqueous solution, and hydrogen bonding or polar interaction if the Adsorption is from non-polar solvents) between the adsorbed Surfactants. Based on the two-step Adsorption model and the mass action treatment, a general Adsorption isotherm equation has been derived. The equation shows that the adsorbed amount Γ depends on the equilibrium concentration C, saturated Adsorption Γ∞, the surface aggregation number (of surface micelle) n, and the equilibrium constants k1 and k2 for the first and second step, respectively. The equation has been applied to various types of Surfactant Adsorption isotherms on various adsorbents from both aqueous and non-aqueous solutions (including Langmuir-, S-, and LS-types) successfully. From the results of the thermodynamics of Adsorption, one can conclude that when dealing with Adsorption from aqueous solution, the second step of Surfactant Adsorption (i.e. surface micellization) is an entropy-driven process similar to the micellization in bulk aqueous solution. However, as expected, the reverse surface micelle formation from non-polar solvent is not an entropy-driven process. The isotherm equations for individual Adsorptions of Surfactant monomers, surface micelles and unoccupied sites at the surface have also been derived. In addition, by combining the general isotherm equation and the Gibbs Adsorption equation, the interfacial pressure-concentration relationships have been derived. Therefore, one can expect that knowledge of two-dimensional states and transitional phases of adsorbed Surfactant films at solid/liquid interfaces could be provided by this kind of investigation.

  • Surfactant Adsorption and surface micellization
    Advances in Colloid Structures, 1
    Co-Authors: Bu-yao Zhu, H. Rupprecht
    Abstract:

    This paper briefly reviews a new Adsorption theory particularly applicable to Surfactant Adsorption. A one-step model of surface micellization is first introduced. By using the mass-action law treatment, an S-type isotherm equation is derived which explains the Adsorption of nonionic Surfactants from aqueous solution onto polar adsorbents. However, the Adsorption of ionic Surfactant generally shows two-step character. First the surface-active species are adsorbed through electrostatic attraction and/or van der Walls interaction. The second step involves hydrophobic interaction if the Adsorption is from aqueous solution, and hydrogen bonding or other polar interaction if from non-polar solvent. Under these conditions a general Adsorption isotherm equation is derived. The model indicates that the size of surface micelles is usually much smaller than that of corresponding bulk micelles. From thermodynamics of Adsorption, it is evident that when dealing with Adsorption from aqueous solution, the second step, i.e. surface micellization, is an entropy-driven process similar to the bulk micellization.

Jeffrey H. Harwell - One of the best experts on this subject based on the ideXlab platform.

  • Improved oil recovery by reducing Surfactant Adsorption with polyelectrolyte in high saline brine
    Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2016
    Co-Authors: Mahesh Budhathoki, Sai Hari Ram Barnee, Bor-jier Shiau, Jeffrey H. Harwell
    Abstract:

    Abstract Surfactant Adsorption on reservoir rock is one of the biggest challenges of chemical enhanced oil recovery (cEOR) techniques. This problem can become severe in high saline brine environments. In this work, the efficacy of a polyelectrolyte, polystyrene sulfonate (PSS), as a sacrificial agent for lowering Surfactant Adsorption from reservoir brine that has totally dissolved solids (TDS) of over 300,000 mg/l is investigated. Four different molecular weight PSSs are evaluated through equilibrium and dynamic Adsorption studies carried out on Berea sandstone and Ottawa sand. Results show significant reduction in Surfactant Adsorption after PSSs addition. The effects of Surfactant/PSS addition techniques, sequential and simultaneous, on Surfactant and/or PSS Adsorptions are also studied. Sand pack studies are conducted to evaluate the effect of PSS-minimized Surfactant Adsorption on oil mobilization/recovery. Results show substantial improvement in oil recovery in the presence of PSS, suggesting a potential as a sacrificial agent in cEOR.

  • Improved oil recovery by reducing Surfactant Adsorption with polyelectrolyte in high saline brine A Physicochemical and engineering aspects
    Colloids and Surfaces, 2016
    Co-Authors: Mahesh Budhathoki, Sai Hari Ram Barnee, Bor-jier Shiau, Jeffrey H. Harwell
    Abstract:

    Surfactant Adsorption on reservoir rock is one of the biggest challenges of chemical enhanced oil recovery (cEOR) techniques. This problem can become severe in high saline brine environments. In this work, the efficacy of a polyelectrolyte, polystyrene sulfonate (PSS), as a sacrificial agent for lowering Surfactant Adsorption from reservoir brine that has totally dissolved solids (TDS) of over 300,000mg/l is investigated. Four different molecular weight PSSs are evaluated through equilibrium and dynamic Adsorption studies carried out on Berea sandstone and Ottawa sand. Results show significant reduction in Surfactant Adsorption after PSSs addition. The effects of Surfactant/PSS addition techniques, sequential and simultaneous, on Surfactant and/or PSS Adsorptions are also studied. Sand pack studies are conducted to evaluate the effect of PSS-minimized Surfactant Adsorption on oil mobilization/recovery. Results show substantial improvement in oil recovery in the presence of PSS, suggesting a potential as a sacrificial agent in cEOR.

  • Disrupting admicelle formation and preventing Surfactant Adsorption on metal oxide surfaces using sacrificial polyelectrolytes.
    Langmuir : the ACS journal of surfaces and colloids, 2014
    Co-Authors: Javen S. Weston, Jeffrey H. Harwell, Benjamin J Shiau, Mahfuz Kabir
    Abstract:

    The Adsorption of anionic, cationic, and nonionic Surfactants was measured on high-surface area silica and alumina nanoparticles when in the presence of the proposed polyelectrolyte sacrificial agents. Surfactant Adsorption was characterized using two types of Adsorption isotherms: one with constant polymer concentration and varying Surfactant concentration, and another with a varying polymer concentration and constant Surfactant concentration. Polystyrenesulfonate and Polydiallyl dimethylammonium chloride were tested as potential sacrificial agents on alumina and silica, respectively. Each Surfactant/polymer system was allowed to reach equilibrium and supernatant Surfactant concentrations were measured. This information was then plotted in order to determine what, if any, effect the proposed sacrificial agent had on the equilibrium Adsorption. Results indicate that both of these polymers can have a large effect on total Surfactant Adsorption at a variety of Surfactant concentrations.

  • Surfactants: Surfactant Adsorption in Porous Media
    Surfactants, 2000
    Co-Authors: Laura L. Wesson, Jeffrey H. Harwell
    Abstract:

    An overview of some of the significant findings of Surfactant Adsorption research is presented. Subjects include the importance of Surfactant Adsorption in petroleum applications, some history of Surfactant Adsorption research, the mechanisms which have been proposed to explain observed Adsorption behavior, and a review of several significant Surfactant Adsorption studies. The emphasis of this review is understanding the mechanisms of Surfactant Adsorption as they relate to applications of Surfactants in petroleum processes. Introduction Surfactants have a variety of applications in the petroleum industry, and Surfactant Adsorption is a consideration in any application where Surfactants come in contact with a solid surface. In enhanced or improved oil recovery (EOR or IOR) Surfactants can be used in classic micellar/polymer (Surfactant) flooding, alkaline/Surfactant/polymer (ASP) flooding or in foams for mobility control or blocking and diverting. Surfactants can act in several ways to enhance oil production: by reducing the interfacial tension between oil trapped in small capillary pores and the water surrounding those pores, thus allowing the oil to be mobilized; by solubilizing oil (some micellar systems); by forming emulsions of oil and water (alkaline methods); by changing the wettability of the oil reservoir (alkaline methods) or by simply enhancing the mobility of the oil. In selecting a suitable Surfactant for any EOR application, one of the criteria for economic success is minimizing Surfactant loss to Adsorption.

  • Reducing Surfactant Adsorption in Carbonate Reservoirs
    Spe Reservoir Engineering, 1993
    Co-Authors: Tabatabal Ahmadall, Jeffrey H. Harwell, Marla V. Gonzalez, John F. Scamehorn
    Abstract:

    This paper compares the Adsorption of anionic and cationic Surfactants on carbonate minerals. It shows that, in general, cationic Surfactants may exhibit significantly less Adsorption on carbonate minerals than that exhibited by anionic Surfactants. It is also shown that cationic Surfactant Adsorption on carbonates may be reduced dramatically by the presence of divalent cations, an environment in which the precipitation of anionic Surfactants might make their use impractical. It is recommended that cationic Surfactants be considered for use in miscible flooding with CO 2

Kartic C. Khilar - One of the best experts on this subject based on the ideXlab platform.

  • a review on experimental studies of Surfactant Adsorption at the hydrophilic solid water interface
    Advances in Colloid and Interface Science, 2004
    Co-Authors: Santanu Paria, Kartic C. Khilar
    Abstract:

    The progresses of understanding of the Surfactant Adsorption at the hydrophilic solid–liquid interface from extensive experimental studies are reviewed here. In this respect the kinetic and equilibrium studies involves anionic, cationic, non-ionic and mixed Surfactants at the solid surface from the solution. Kinetics and equilibrium Adsorption of Surfactants at the solid–liquid interface depend on the nature of Surfactants and the nature of the solid surface. Studies have been reported on Adsorption kinetics at the solid–liquid interface primarily on the Adsorption of non-ionic Surfactant on silica and limited studies on cationic Surfactant on silica and anionic Surfactant on cotton and cellulose. The typical isotherm of Surfactants in general, can be subdivided into four regions. Four-regime isotherm was mainly observed for Adsorption of ionic Surfactant on oppositely charged solid surface and Adsorption of non-ionic Surfactant on silica surface. Region IVof the Adsorption isotherm is commonly a plateau region above the CMC, it may also show a maximum above the CMC. Isotherms of four different regions are discussed in detail. Influences of different parameters such as molecular structure, temperature, salt concentration that are very important in Surfactant Adsorption are reviewed here. Atomic force microscopy study of different Surfactants show the self-assembly and mechanism of Adsorption at the solid–liquid interface. Adsorption behaviour and mechanism of different mixed Surfactant systems such as anionic–cationic, anionic– non-ionic and cationic–non-ionic are reviewed. Mixture of surface-active materials can show synergistic interactions, which can be manifested as enhanced surface activity, spreading, foaming, detergency and many other phenomena. D 2004 Elsevier B.V. All rights reserved.

Rob Atkin - One of the best experts on this subject based on the ideXlab platform.

  • ph dependent surface charge at the interfaces between aluminum gallium nitride algan and aqueous solution revealed by Surfactant Adsorption
    Journal of Colloid and Interface Science, 2021
    Co-Authors: Jianan Wang, Xing Zhang, Constance Wang, Stacia Keller, Umesh K. Mishra, Brett Nener, Giacinta Parish, Rob Atkin
    Abstract:

    Abstract Hypothesis The net surface charge of AlGaN/GaN structures, where AlGaN is in contact with the solution, is controlled by the pH-dependent protonation and deprotonation of the surface hydroxyl groups and possibly the electron-deficient surface electronic states. We hypothesize that atomic force microscopy (AFM) force measurements of ionic Surfactant Adsorption can reveal how the AlGaN surface properties vary with pH. Experiments AFM force curves and images were used to probe the AlGaN/solution interface in water as a function of pH, and with added cationic Surfactant cetyltrimethylammonium bromide (CTAB) or anionic Surfactant sodium dodecylsulfate (SDS). Findings The AlGaN/solution interface is negatively charged at pH 12, has an isoelectric point near pH 5.5, and is positively charged at pH values less than 5.5. Surfactant Adsorption data suggests AlGaN surface is somewhat hydrophobic at acidic pH. Compared to gallium nitride (GaN), at pH 2, AlGaN has a lower charge density and hydrophobicity, but at other values of pH, the surface properties of AlGaN and GaN are similar.

  • pH-dependent surface properties of the gallium nitride - Solution interface mapped by Surfactant Adsorption.
    Journal of colloid and interface science, 2019
    Co-Authors: Jianan Wang, Xing Zhang, Constance Wang, Stacia Keller, Umesh K. Mishra, Brett Nener, Giacinta Parish, Rob Atkin
    Abstract:

    Abstract Hypothesis The surface charge of gallium nitride (GaN) in contact with solution is controlled by pH via surface protonation and deprotonation, similar to silica. Ionic Surfactants adsorb on surfaces via electrostatic and hydrophobic interactions and can be utilized to reflect the surface charge of GaN. Experiments The surface charge properties of Ga-polar GaN in solution were probed as a function of pH using atomic force microscopy (AFM). AFM soft-contact images and force curves were used to study the pH-dependent Adsorption of the cationic Surfactant cetyltrimethylammonium bromide (CTAB) and anionic Surfactant sodium dodecylsulfate (SDS) on GaN surfaces. To further confirm the AFM results, GaN/AlGaN/GaN heterostructure-based ion sensing devices were used to measure the Surfactant Adsorption over the same pH range. Findings SDS aggregates adsorb on GaN below pH 2.75 while CTAB aggregates adsorb above pH 10. This shows that the GaN surface carries substantial net positive charge at low pH, and negative charge at high pH. There is no clear SDS or CTAB Adsorption on the GaN surface between pH 3 and 9.75, which indicates the surface is weakly charged. GaN/AlGaN/GaN heterostructure-based devices confirm these results, and demonstrate the utility of these devices for measuring Surfactant Adsorption.

  • mechanism of cationic Surfactant Adsorption at the solid aqueous interface
    Advances in Colloid and Interface Science, 2003
    Co-Authors: Rob Atkin, Vincent S J Craig, Erica J Wanless, Simon Biggs
    Abstract:

    Until recently, the rapid time scales associated with the formation of an adsorbed Surfactant layer at the solid-aqueous interface has prevented accurate investigation of Adsorption kinetics. This has led to the mechanism of Surfactant Adsorption being inferred from thermodynamic data. These explanations have been further hampered by a poor knowledge of the equilibrium adsorbed Surfactant morphology, with the structure often misinterpreted as simple monolayers or bilayers, rather than the discrete surface aggregates that are present in many Surfactant-substrate systems. This review aims to link accepted equilibrium data with more recent kinetic and structural information in order to describe the Adsorption process for ionic Surfactants. Traditional equilibrium data, such as Adsorption isotherms obtained from depletion approaches, and the most popular methods by which these data are interpreted are examined. This is followed by a description of the evidence for discrete aggregation on the substrate, and the morphology of these aggregates. Information gained using techniques such as atomic force microscopy, fluorescence quenching and neutron reflectivity is then reviewed. With this knowledge, the kinetic data obtained from relatively new techniques with high temporal resolution, such as ellipsometry and optical reflectometry, are examined. On this basis the likely mechanisms of Adsorption are proposed.

Kourosh Rajaei - One of the best experts on this subject based on the ideXlab platform.

  • Lignin As a Potential Additive For Minimizing Surfactant Adsorption On Clay Minerals In Different Electrolyte Concentration
    Day 3 Wed August 07 2019, 2019
    Co-Authors: Jibril Tumba, Kourosh Rajaei, Augustine Agi, Afeez O. Gbadamosi, Radzuan Junin, Azza Abbas, Jeffrey Gbonhinbor
    Abstract:

    Abstract The use of Surfactants in chemical enhanced oil recovery can recover more oil trapped in the reservoir. However, the loss of Surfactant due to Adsorption on porous media renders the process ineffective and economically unfeasible. In this study, the Adsorption of sodium dodecyl sulfate (SDS) and 4-octylphenol polyethoxylated (TX-100) on different clay minerals (kaolinite, montmorillonite, illite and quartz) as a function of the Surfactant concentration, pH and salinity has been investigated. Besides, the use of lignin alkali as a sacrificial agent to reduce Adsorption of Surfactants in the reservoir is proposed. Surfactant Adsorption on the different minerals was determined using the surface tension technique and batch equilibrium Adsorption process with lignin as sacrificial agent. The experiment was conducted at varying pH and electrolyte concentrations. Furthermore, oil displacement test was conducted in a sandpack to determine the amount of oil recovered by the Surfactant before and after pre-flush with lignin alkaline. Experimental result reveals that SDS adsorbed more on kaolinite while, TX-100 on montmorillonite. The decrease in pH increased the Adsorption of SDS on kaolinite and illite, meanwhile, the Adsorption of TX-100 on montmorillonite increased significantly at low pH. The optimum salinity concentration for both Surfactants was at 20,000ppm for all the minerals except for kaolinite which was at 30,000ppm. Lignin alkaline reduced the Surfactant Adsorption by 50% and 53.2% for SDS and TX-100 respectively. Oil displacement test with SDS and TX-100 Surfactants after water flooding had additional recovery of 7.44% and 4.18% respectively while, after pre-flush the recovery increased by 2.2%.

  • Application of henna extract in minimizing Surfactant Adsorption on quartz sand in saline condition: A sacrificial agent approach
    SN Applied Sciences, 2019
    Co-Authors: Mohd Syazwan Mohd Musa, Wan Rosli Wan Sulaiman, Zaiton Abdul Majid, Zulkifli Abdul Majid, Ahmad Kamal Idris, Kourosh Rajaei
    Abstract:

    This study examined the Adsorption ability of henna extract as an environment-friendly and accessible sacrificial agent. In this study, the Fourier transform infrared-attenuated total reflectance (FTIR-ATR) was used to characterized henna extract and quartz sand. The Adsorption of the henna extract on quartz sand was executed using the ultraviolet–visible spectroscopy (UV–Vis). The current study also assesses the effects of salinity on the henna extract Adsorption on quartz sand, and the mechanisms of the Adsorption process were interpreted. Apart from that, the ability of henna extract in reducing the Adsorption of Surfactant in the presence of salts were recorded. The outcome demonstrated that henna extract Adsorption on quartz sand increased with the increase of salinity concentrations. Note that the Adsorption value increased from 3.14 to 8.11 mg/g in 0 and 50,000 mg/L of salinity, respectively. The main mechanisms involved in the Adsorption process were hydrogen bond, hydrophobic interactions, and electrostatic attractions. A reduction of 46% of Surfactant Adsorption was observed. This was a profound decrease in the Adsorption of Surfactant in the presence of henna extract, suggesting a possibility to be utilized as a sacrificial agent in reducing Surfactant Adsorption.

  • Henna extract as a potential sacrificial agent in reducing Surfactant Adsorption on kaolinite: The role of salinity
    Journal of King Saud University: Engineering Sciences, 2019
    Co-Authors: Mohd Syazwan Mohd Musa, Wan Rosli Wan Sulaiman, Zaiton Abdul Majid, Zulkifli Abdul Majid, Ahmad Kamal Idris, Kourosh Rajaei
    Abstract:

    Abstract The Adsorption ability of henna extract as a cheap, environment-friendly and easily available sacrificial agent was investigated. Fourier transform infrared-attenuated total reflectance (FTIR-ATR) was used to characterized henna extract and kaolinite. The Adsorption of henna extract on kaolinite was done using Ultraviolet–visible spectroscopy (UV–Vis). The effects of salinity on the henna extract Adsorption on kaolinite were studied. The mechanisms of the Adsorption process were interpreted. Also, henna extract performances in reducing the Adsorption of Surfactant in the proximity of salts were assessed. The outcome shows that henna extract Adsorption on kaolinite was increased with increasing salinity concentrations. The Adsorption value increased from 7.88 to 13.35 mg/g in 0 and 50,000 mg/L of salinity respectively. The mechanisms involved in the Adsorption process were mainly hydrogen bond, hydrophobic interactions, and electrostatic attractions. A reduction of 53% of Surfactant Adsorption was observed and showed a profound decrease in the Adsorption of Surfactant in the presence of henna extract suggesting a possibility to be utilized as a sacrificial agent in reducing Surfactant Adsorption.