WorldWideScience

Sample records for nonionic surfactant systems

  1. A conductometric investigation of hydroxypropylmethyl cellulose/sodium dodecyl sulfate/nonionic surfactant systems

    Directory of Open Access Journals (Sweden)

    Petrović Lidija B.

    2014-01-01

    Full Text Available Surfactant mixtures are very often used in various cosmetic and pharmaceutical products because they commonly act in synergism and provide more favorable properties than the single surfactants. At the same time, the 9 presence of polymers in mixtures of surfactants may lead to molecular interactions thereby affecting product stability and activity. For these reasons it is very important to determine the surfactant interactions influence on 1micellization and mixed micellization, as well as polymer-surfactants mixed micelles interactions. In this work we examined self-aggregation of nonionic surfactants, polysorbate 20 (Tween 20, polyoxyethylene octylphenyl ether (Triton X100 and polyoxyethylene-polyoxypropylene block copolymer (Pluronic F68 with ionic surfactant, sodium dodecylsulfate, in aqueous solution at 40ºC using conductometric titration method. It was found that concentration region for mixed micelle formation depends on nonionic surfactant characteristics and its concentration. Formation of surfactants mixed micelles in the presence of nonionic polymer, hydroxypropylmethyl cellulose, and their binding to polymer hydrophobic sites, were investigated too. Analysis of obtained results points to different kinds of interactions in investigated systems, which are crucial for their application. [Projekat Ministarstva nauke Republike Srbije, br. III 46010

  2. Packing states of multilamellar vesicles in a nonionic surfactant system

    DEFF Research Database (Denmark)

    Le, T.D.; Olsson, U.; Mortensen, K.

    2001-01-01

    under shear. Here, we focused only in the MLV region, L-alpha(*), of a temperature sensitive surfactant system (C12E4-water) to investigate the packing of multilamellar vesicles as a function of temperature under constant shear. Two sets of temperature scan experiments were performed in the L...

  3. Rheological properties of novel viscoelastic micelle systems containing anionic-nonionic dimeric surfactant

    Institute of Scientific and Technical Information of China (English)

    方波; 曹丹红; 江体乾

    2008-01-01

    The viscoelastic micelle systems formed by novel anionic-nonionic dimeric surfactant and conventional cationic surfactant cetyltrimethylammonium(1631) were studied.The viscoelasticity,thixotropy,flow curves and constitutive equation for the novel viscoelastic micelle systems were investigated.The results show that the micelle systems possess viscoelasticity,thixotropy,and shear thinning property.Some micelle systems possess hysteresis loops showing both viscoelasticity and thixotropy.It is proved that the flow curves are characterized by the co-rotational Jeffreys constitutive equation correctly.

  4. Effect of non-ionic surfactants on interfacial rheological properties of water/oil systems

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos-Szabo, J.; Lakatos, I. (Magyar Tudomanyos Akademia, Miskolc-Egyetemvaros (Hungary))

    1989-10-01

    The interfacial rheological properties of characteristic Hungarian oil/water systems are discussed. It is shown that there are differences of several orders of magnitude in interfacial viscosities and in majority of cases the boundary layers have non-Newtonian flow behaviour. The study of tenside solutions proved that ethoxylated nonylphenols significantly reduce both the interfacial viscosity and the non-Newtonian character. The shorter the ethoxy chain in the monomer molecule, the greater the effect of nonionic surfactants. The concentration also enhances the effect and the phenomena can be explained by formation of closely packed adsorption layer between the phases. The results may contribute to elucidation of displacement mechanism, spontaneous emulsification, coalescence of dispersed systems etc. in presence of nonionic surfactants. (orig.).

  5. Biotoxicity and bioavailability of hydrophobic organic compounds solubilized in nonionic surfactant micelle phase and cloud point system.

    Science.gov (United States)

    Pan, Tao; Liu, Chunyan; Zeng, Xinying; Xin, Qiao; Xu, Meiying; Deng, Yangwu; Dong, Wei

    2017-06-01

    A recent work has shown that hydrophobic organic compounds solubilized in the micelle phase of some nonionic surfactants present substrate toxicity to microorganisms with increasing bioavailability. However, in cloud point systems, biotoxicity is prevented, because the compounds are solubilized into a coacervate phase, thereby leaving a fraction of compounds with cells in a dilute phase. This study extends the understanding of the relationship between substrate toxicity and bioavailability of hydrophobic organic compounds solubilized in nonionic surfactant micelle phase and cloud point system. Biotoxicity experiments were conducted with naphthalene and phenanthrene in the presence of mixed nonionic surfactants Brij30 and TMN-3, which formed a micelle phase or cloud point system at different concentrations. Saccharomyces cerevisiae, unable to degrade these compounds, was used for the biotoxicity experiments. Glucose in the cloud point system was consumed faster than in the nonionic surfactant micelle phase, indicating that the solubilized compounds had increased toxicity to cells in the nonionic surfactant micelle phase. The results were verified by subsequent biodegradation experiments. The compounds were degraded faster by PAH-degrading bacterium in the cloud point system than in the micelle phase. All these results showed that biotoxicity of the hydrophobic organic compounds increases with bioavailability in the surfactant micelle phase but remains at a low level in the cloud point system. These results provide a guideline for the application of cloud point systems as novel media for microbial transformation or biodegradation.

  6. The solubilization of fatty acids in systems based on block copolymers and nonionic surfactants

    Science.gov (United States)

    Mirgorodskaya, A. B.; Yatskevich, E. I.; Zakharova, L. Ya.

    2010-12-01

    The solubilizing action of micellar, microemulsion, and polymer-colloid systems formed on the basis of biologically compatible amphiphilic polymers and nonionic surfactants on capric, lauric, palmitic, and stearic acids was characterized quantitatively. Systems based on micelle forming oxyethyl compounds increased the solubility of fatty acids by more than an order of magnitude. Acid molecules incorporated into micelles increased their size and caused structural changes. Solubilization was accompanied by complete or partial destruction of intrinsic acid associates and an increase in their p K a by 1.5-2 units compared with water.

  7. Wormlike micelles in mixed amino acid surfactant/nonionic surfactant aqueous systems and the effect of added electrolytes.

    Science.gov (United States)

    Shrestha, Rekha Goswami; Rodriguez-Abreu, Carlos; Aramaki, Kenji

    2009-01-01

    The formation of viscoelastic wormlike micelles in mixed amino acid surfactant/nonionic surfactant aqueous systems in the presence of different counterions and salts is reported, and the effects of the different electrolytes on the rheological behavior are discussed. N-dodecanoylglutamic acid (LAD) is neutralized with biologically relevant L-lysine and L-arginine to obtain anionic surfactants (LAD-Lys2, LAD-Arg2) which form aqueous micellar solutions at 25 degrees C. Addition of a nonionic surfactant, tri-ethyleneglycol mono n-tetradecyl ether (C14EO3), to the aqueous solutions of both LAD-Lys2 and LAD-Arg2 causes the zero-shear viscosity (eta(0)) to increase with C14EO3 concentration gradually at first, and then sharply, indicating one-dimensional growth of the aggregates and eventual formation of entangled wormlike micelles. Further addition of C14EO3 ultimately leads to phase separation of liquid crystals. Such a phase separation, which limits the maximum attainable viscosity, takes place at lower C14EO3 concentrations for LAD-Lys2 compared to LAD-Arg2 systems. It was found that the rheological behavior of micellar solutions is significantly affected by the addition of Na+X(-) salts (X = Cl(-), Br(-), I(-), NO3(-)). The maximum viscosities obtained for the systems with added salt are all higher than that of the salt-free system, and the onset of wormlike micelle formation shift towards lower nonionic surfactant concentrations upon addition of electrolyte. The maximum attainable thickening effect of anions increases in the order NO3(-)>I(-)>Br(-)>Cl(-). The effect of temperature was also investigated. Phase separation takes place at certain temperature, which depends on the type of anion in the added salt, and decreases in the order I(-)>NO3(-)>Br(-) approximately equal Cl(-), in agreement with Hofmeister's series in terms of amphiphile solubility. The thermoresponsive rheological behavior was also found to be highly dependent on the type of anion, and anomalous

  8. Threshold for spontaneous oscillation in a three-phase liquid membrane system involving nonionic surfactant.

    Science.gov (United States)

    Nanzai, Ben; Funazaki, Tomohisa; Igawa, Manabu

    2010-09-16

    This study of self-oscillation was conducted using a new three-phase liquid membrane system of ethanol aqueous solution, benzyl alcohol solution with nonionic surfactant, and pure water. Relations of the initial ethanol concentration to the oscillation amplitude and frequency, and to the induction period before oscillations were investigated. The oscillation amplitude is independent of the initial ethanol concentration, but the frequency and the induction period are related to it. The oscillation frequency increased concomitantly with the increased ethanol initial concentration, but the induction period before the electrical oscillations decreased with increasing concentration. To estimate the influence of ethanol diffusion on the electrical oscillations, the ethanol concentration in each phase was measured using separate experiments after different durations of oscillation. The diffusion coefficient was calculated using Fick's second law. Results show successful estimation of the threshold for oscillations. The threshold is defined in terms of the ethanol concentration at the interface between the benzyl alcohol phase and the pure water phase.

  9. Nonionic surfactant vesicular systems for effective drug delivery—an overview

    Directory of Open Access Journals (Sweden)

    Gannu P. Kumar

    2011-12-01

    Full Text Available Vesicular systems are a novel means of drug delivery that can enhance bioavailability of encapsulated drug and provide therapeutic activity in a controlled manner for a prolonged period of time. Liposomes were the first such system but they suffer from a number of drawbacks including high cost and lack of stability at various pHs. Niosomes are a nonionic surfactant vesicular system, which can be easily and reliably made in the laboratory. Many factors affect noisome formation such as the method of manufacture, nature of surfactant and encapsulated drug, temperature at which the lipids are hydrated and the critical packing parameter. This review describes all aspects of niosomes including their different compositions, the various methods of preparation, the effect of changing manufacturing parameters, methods of characterization, factors that affect their stability, their use by various routes of administration, their therapeutic applications and the most important patents. The review also provides detailed information of the various types of niosomes that provide effective drug delivery.

  10. The effects of nonionic surfactants on the tris(2,2'-bipyridyl)ruthenium(II)--tripropylamine electrochemiluminescence system.

    Science.gov (United States)

    Workman, S; Richter, M M

    2000-11-15

    The electrochemistry and electrogenerated chemiluminescence (ECL) of Ru(bpy)3(2+) (bpy = 2,2'-bipyridyl) were studied in the presence of the nonionic surfactants Triton X-100, Thesit, and Nonidet P40. The anodic oxidation of Ru(bpy)3(2+) produces ECL in the presence of tri-n-propylamine in both aqueous and surfactant solutions. Increases in both ECL efficiency (> or =8-fold) and duration of the ECL signal were observed in surfactant media. A shift to lower energies of the Ru(bpy)3(2+) ECL emission by approximately 8 nm was also observed. The one-electron oxidation of Ru(bpy)3(2+) to Ru(bpy)3(3t) occurs at + 1.03 V vs Ag/AgCl in aqueous buffered (0.2 M potassium phosphate) solution as found by square wave voltammetry. This potential did not shift in surfactant systems, indicating that the redshifts in ECL emission are due to stabilization of ligand pi* orbitals in the metal-to-ligand charge-transfer excited state. These results are consistent with hydrophobic interactions between Ru(bpy)3(2+) and the nonionic surfactants.

  11. Interaction of Fluorocarbon Containing Hydrophobically Modified Polyelectrolyte with Nonionic Surfactants

    Institute of Scientific and Technical Information of China (English)

    GUO,Jin-Feng(郭金峰); ZHUANG,Dong-Qing(庄东青); ZHOU,Hui(周晖); ZHANG,Yun-Xiang(章云祥)

    2002-01-01

    The interaction of fluorocarbon containing hydrophobically modified polyelectrolyte (FMPAANa) with two kinds of nonionic surfactants (hydrogenated and fluorinated) in a semidilute (0.5 wt% ) aqueous solution had been studied by rheological measurements. Association behavior was found in both systems. The hydrophobic interaction of FMPAANa with fluorinated surfactant (FC171) is much stronger than that with hydrogenated surfactant (NP7.5) at low surfactant concentrations. The interaction is strengthened by surfactants being added for the density of active junctions increased. Whereas distinct phenomena for FC171 and NP7. 5 start to be found as the surfactants added over their respective certain concentration. The interaction of polyelectrolyte with fluorinated surfactant increases dramatical ly while that with hydrogenated surfactant decreases.

  12. Interaction of nonionic surfactant AEO9 with ionic surfactants

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-guo; YIN Hong

    2005-01-01

    The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammonium bromide (CTAB) at molar fraction of AEO9, αAEO9 =0.5. The surface properties of the surfactants, critical micelle concentration (CMC),effectiveness of surface tension reduction (γCMC), maximum surface excess concentration (Гmax) and minimum area per molecule at the air/solution interface (Amin) were determined for both individual surfactants and their mixtures. The significant deviations from ideal behavior (attractive interactions) of the nonionic/ionic surfactant mixtures were determined. Mixtures of both AEO9/SDS and AEO9/CTAB exhibited synergism in surface tension reduction efficiency and mixed micelle formation, but neither exhibited synergism in surface tension reduction effectiveness.

  13. Optimization of isothermal low-energy nanoemulsion formation: hydrocarbon oil, non-ionic surfactant, and water systems.

    Science.gov (United States)

    Komaiko, Jennifer; McClements, David Julian

    2014-07-01

    Nanoemulsions can be fabricated using either high-energy or low-energy methods, with the latter being advantageous because of ease of implementation, lower equipment and operation costs, and higher energy efficiency. In this study, isothermal low-energy methods were used to spontaneously produce nanoemulsions using a model system consisting of oil (hexadecane), non-ionic surfactant (Brij 30) and water. Rate and order of addition of surfactant, oil and water into the final mixture were investigated to identify optimal conditions for producing small droplets. The emulsion phase inversion (EPI) and spontaneous emulsion (SE) methods were found to be the most successful, which both require the surfactant to be mixed with the oil phase prior to production. Order of addition and surfactant-to-oil ratio (SOR) influenced the particle size distribution, while addition rate and stirring speed had a minimal effect. Emulsion stability was strongly influenced by storage temperature, with droplet size increasing rapidly at higher temperatures, which was attributed to coalescence near the phase inversion temperature. Nanoemulsions with a mean particle diameter of approximately 60 nm could be produced using both EPI and SE methods at a final composition of 5% hexadecane and 1.9% Brij 30, and were relatively stable to droplet growth at temperatures <25 °C.

  14. Preparation and evaluation of sulphonamide nonionic surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, M. H. M.

    2010-07-01

    Alkyl (octyl, decyl and dodecyl; C{sub 8}, C{sub 1}0 and C{sub 1}2) benzene sulphonyl chloride was used in the preparation of a novel series of nonionic surfactants (IV-VI)a-c, (VII-IX) a-c and (X-XII)a-c. The preparations were completed by reacting each alkyl (C{sub 8}, C{sub 1}0 and C{sub 1}2) benzene sulphonyl chloride with ethanolamine to give (I-III) respectively. The resulting products were reacted separately with ethylene oxide in the presence of different (base KOH, Lewis acid SnCl4 and k10 clay) catalysts to produce different moles of nonionic surfactants (5, 7 and 9) in sequence corresponding to (IV-VI)a-c, (VII-IX) a-c and (X-XII)a-c respectively. The chemical structures of prepared nonionic surfactants were elucidated by IR and 1HNMR spectra. The surface activity, biodegradability and biological activities of the prepared compounds were investigated. The obtained data show that these compounds have good surface and biological activities as well as reasonable biodegradability properties. (Author) 30 refs.

  15. Interaction of nonionic surfactant AEO9 with ionic surfactants*

    OpenAIRE

    2005-01-01

    The interaction in two mixtures of a nonionic surfactant AEO9 (C12H25O(CH2CH2O)9H) and different ionic surfactants was investigated. The two mixtures were AEO9/sodium dodecyl sulfate (SDS) and AEO9/cetyltrimethylammonium bromide (CTAB) at molar fraction of AEO9, α AEO9=0.5. The surface properties of the surfactants, critical micelle concentration (CMC), effectiveness of surface tension reduction (γ CMC), maximum surface excess concentration (Γ max) and minimum area per...

  16. Combined effect of nonionic surfactant Tween 80 and DOM on the behaviors of PAHs in soil--water system.

    Science.gov (United States)

    Cheng, K Y; Wong, J W C

    2006-03-01

    Batch experiments were performed to examine the desorption behavior of phenanthrene and pyrene in soil-water system in the presence of nonionic surfactant Tween 80 and dissolved organic matter (DOM) derived from pig manure or pig manure compost. Addition of 150 mgl(-1) Tween 80 desorbed 5.8% and 2.1% of phenanthrene and pyrene from soil into aqueous phase, respectively, while the addition of both Tween 80 and DOM derived from pig manure compost and pig manure could further enhance the desorption of phenanthrene to 15.8% and 16.2%, respectively, and 6.4% and 10.9%, respectively, for pyrene. In addition, our finding also suggested that subsequent addition of Tween 80 into the soil-water system could further enhance PAHs desorption. The enhancement effect of the co-existence of Tween 80 and DOM was more than the additive effect of the Tween 80 and DOM individually. It is likely that the formation of DOM-surfactant complex in the soil-water system may be a possible reason to explain such desorption enhancement phenomenon. Therefore, it is anticipated that the coexistence of both Tween 80 and DOM derived from pig manure or pig manure compost in soil environment will enhance the bioavailability of PAHs as well as other hydrophobic organic contaminants (HOCs) by enhancing the desorption during remediation process.

  17. Salting-out effect induced by temperature cycling on a water/nonionic surfactant/oil system.

    Science.gov (United States)

    Anton, Nicolas; Saulnier, Patrick; Béduneau, Arnaud; Benoit, Jean-Pierre

    2007-04-12

    This paper presents original effects induced by temperature cycling on the transitional phase inversion of emulsions, stabilized by a nonionic polyethoxylated C18E6 surfactant model. The phase inversion follow-up is performed by electrical conductivity measurements, which involves focusing the study on the shape and location of the emulsion inversion region. In that way, new observations are brought out as a gradual evolution of the emulsion inversion along the cycling process. Two alternative approaches are considered for tackling these results: (i) first, a molecular approach regarding the particular organization and rearrangement of water clusters surrounding the surfactant polymer polar head, and (ii) second, a thermodynamic approach only considering the whole Gibbs free energy of the system. The volumic approaches are transposed, here, to the water/oil interface, and disclose that the phase inversion zone is included in a metastable region, able to stabilize for a given temperature, either metastable O/W emulsions or stable W/O ones. In that way, this study proposes novel and complementary insights into the phenomena governing the emulsion phase inversion.

  18. Development and Characterization of Non-Ionic Surfactant Vesicles (Niosomes) for Oral delivery of Lornoxicam

    OpenAIRE

    K B Bini; D. Akhilesh; P.Prabhakara; Kamath J.V

    2012-01-01

    Niosomes are non-ionic surfactant vesicles obtained on hydration of synthetic nonionic surfactants, with or without incorporation of cholesterol or other lipids. They are vesicular systems similar to liposomes that can be used as carriers of amphiphilic and lipophilic drugs. Niosomes are promising vehicle for drug delivery and being non-ionic, it is less toxic and improves the therapeutic index of drug by restricting its action to target cells. They are lamellar structures that are microscopi...

  19. Titration procedure for low ethoxylated nonionic surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Buschmann, N. [Anorganisch-Chemisches Inst., Lehrstuhl fuer Analytische Chemie, Muenster Univ. (Germany); Huelskoetter, F. [Anorganisch-Chemisches Inst., Lehrstuhl fuer Analytische Chemie, Muenster Univ. (Germany)

    1997-01-01

    Highly lipophilic surfactants are frequently used as emulsifiers for preparing oil-in-water emulsions (e.g. coolants lubricants). Typical surfactants used for this purpose are low ethoxylated alcohols and ethoxylated alkylphenols. Due to the low degree of ethoxylation they cannot be analysed by conventional methods. The method described in this article is based on the introduction of an anionic group into the molecule by a derivatization reaction. The reaction product can be determined by conventional titration methods for anionic surfactants without any modification. The use of the new method for other nonionic surfactants like sorbitan esters, (ethoxylated) fatty acid amides or glycerol fatty acid partial esters is also described as well as the sample preparation for coolants lubricants. (orig.) [Deutsch] Lipophile Tenside werden haeufig zur Herstellung von Oel-in-Wasser-Emulsionen verwandt, wie sie beispielsweise in Kuehlschmiermitteln eingesetzt werden. Typische Vertreter dieser Tenside sind niedrig ethoxylierte Fettalkohole und Alkylphenole. Wegen ihres geringen Ethoxylierungsgrades koennen sie mit den konventionellen Methoden nicht analytisch bestimmt werden. Die hier beschriebene Analysenmethode beruht auf der Derivatisierung der Ethoxylate zu entsprechenden anionischen Tensiden (Ethersulfate). Diese koennen ohne weiteres mit den etablierten Titrationsverfahren bestimmt werden. Die Anwendung dieses neuen Verfahrens auf die Bestimmung anderer nichtionischer Tenside - Sorbitanester, (ethoxylierte) Fettsaeureamide und Partialglyceride - wird ebenso beschrieben wie die Probenvorbereitung fuer die Analyse von Kuehlschmiermitteln. (orig.)

  20. Formulation and characterisation of self-microemulsifying drug delivery systems based on biocompatible nonionic surfactants

    Directory of Open Access Journals (Sweden)

    Đekić Ljiljana M.

    2014-01-01

    Full Text Available Development of self-dispersing drug delivery systems (SMEDDS is a modern strategy for oral delivery improvement of poorly soluble drugs. Self-microemulsifying drug delivery systems (SMEDDS are isotropic mixtures of oils and hydrophilic surfactants, which form oil-in-water (o/w microemulsions by dilution in aqueous media (e.g., gastrointestinal fluids. Formulation of SMEDDS carriers requires consideration of a large number of formulation parameters and their influences on process of self-microemulsifying and releasing of drug. The aim of this work was formulation and characterisation of SMEDDS for oral administration of ibuprofen. In the experimental work, two series of potential SMEDDS were prepared (M1-M10, using surfactant (Labrasol®, Gattefosse, cosurfactant (PEG-40 hydrogenated castor (Cremophor® RH40, and oil (medium chain triglycerides (Crodamol® GTCC and olive oil (Cropur® Olive, at surfactant-to-cosurfactant mass ratios (Km 9:1, 7:3, 5:5, 3:7, and 1:9, and 10 % or 20 % of the oil phase. Ibuprofen was dissolved in formulations in concentration of 10 %. Characterisation of the investigated formulations included evaluation of physical stability, self-microemulsification ability in 0,1M HCl (pH 1.2 and phosphate buffer pH 7.2 (USP and in vitro drug release. Formation of o/w microemulsions with the average droplet size (Z-ave up to 100 nm, was observed in dispersions of formulations prepared with 10% w/w of medium chain triglycerides, within the entire investigated range of the Km values (M1-M5. These formulations were selected as SMEDDS. Results of characterisation pointed out the importance of the type and concentration of the oil as well as the Km value for the self-microemulsying ability as well as drug release kinetics from the investigated SMEDDS. Ibuprofen relase was in accordance with the request of USP 30-NF 25 (at least 80 %, after 60 min from the formulations M1 (Km 9:1 and M5 (Km 1:9. Furthermore, ibuprofen release was

  1. Electrophoretic separations in poly(dimethylsiloxane) microchips using mixtures of ionic, nonionic and zwitterionic surfactants.

    Science.gov (United States)

    Guan, Qian; Noblitt, Scott D; Henry, Charles S

    2012-09-01

    The use of surfactant mixtures to affect both EOF and separation selectivity in electrophoresis with PDMS substrates is reported, and capacitively coupled contactless conductivity detection is introduced for EOF measurement on PDMS microchips. First, the EOF was measured for two nonionic surfactants (Tween 20 and Triton X-100), mixed ionic/nonionic surfactant systems (SDS/Tween 20 and SDS/Triton X-100), and finally for the first time, mixed zwitterionic/nonionic surfactant systems (TDAPS/Tween 20 and TDAPS/Triton X-100). EOF for the nonionic surfactants decreased with increasing surfactant concentration. The addition of SDS or TDAPS to a nonionic surfactant increased EOF. After establishing the EOF behavior, the separation of model catecholamines was explored to show the impact on separations. Similar analyte resolution with greater peak heights was achieved with mixed surfactant systems containing Tween 20 and TDAPS relative to the single surfactant system. Finally, the detection of catecholamine release from PC12 cells by stimulation with 80 mM K(+) was performed to demonstrate the usefulness of mixed surfactant systems to provide resolution of biological compounds in complex samples.

  2. Preparation and evaluation of sulphonamide nonionic surfactants

    Directory of Open Access Journals (Sweden)

    Ahmed, M. H. M.

    2010-03-01

    Full Text Available Alkyl (octyl, decyl and dodecyl; C8,C10 and C12 benzene sulphonyl chloride was used in the preparation of a novel series of nonionic surfactants (IV-VIa-c, (VII-IX a-c and (X-XIIa-c. The preparations were completed by reacting each alkyl (C8,C10 and C12 benzene sulphonyl chloride with ethanolamine to give (I-III respectively. The resulting products were reacted separately with ethylene oxide in the presence of different (base KOH, Lewis acid SnCl4 and k10 clay catalysts to produce different moles of nonionic surfactants (5, 7 and 9 in sequence corresponding to (IV-VIa-c, (VII-IX a-c and (X-XIIa-c respectively. The chemical structures of prepared nonionic surfactants were elucidated by IR and 1HNMR spectra. The surface activity, biodegradability and biological activities of the prepared compounds were investigated. The obtained data show that these compounds have good surface and biological activities as well as reasonable biodegradability properties.Cloruros de sulfonilbenceno alquilados (octil, decil, dodecil; C8, C10 y C12 fueron usados en la preparación de una nueva serie de surfactantes no iónicos (IV-VIa-c, (VII-IX a-c and (X-XIIa-c. Las preparaciones fueron completadas por reacción de cada cloruro de sulfonilbenceno alquilado (C8, C10 y C12 con etanolamina para dar los compuestos (IIII, respectivamente. Los anteriores productos reaccionaron separadamente con óxido de etileno en presencia de diferentes catalizadores (la base KOH, el ácido de Lewis SnCl4 y la arcilla k10 para producir secuencialmente diferentes surfactantes no iónicos con distintos moles de óxido de etileno (5, 7 y 9: (IV-VIa-c, (VII-IXa-c and (X-XIIa-c, respectivamente. La estructura química de los surfactantes no iónicos preparados fueron elucidadas mediante sus espectros de IR y 1H RMN. Las propiedades tensoactivas, biodegradabilidad y actividad biológica de los compuestos preparados fueron investigados. Los datos obtenidos muestran que estos compuestos tienen

  3. Silicone antifoam performance enhancement by nonionic surfactants in potato medium.

    Science.gov (United States)

    Christiano, Steven P; Fey, Kenneth C

    2003-01-01

    The ability of a silicone antifoam to retard foaming in a liquor prepared from potatoes is enhanced by the addition of ethoxylated nonionic surfactants. The enhancement is non-linear for surfactant concentration, with all 12 surfactants tested possessing a concentration at which foam heights strongly diminish, referred to as the surfactant critical antifoaming concentration (SCAFC). SCAFCs vary between surfactants, with lower values indicating better mass efficiency of antifoaming enhancement. SCAFCs decrease with degree of ethoxylation and decrease with the hydrophilic-lipophilic balance for ethoxylated nonionic surfactants. Surfactant addition produces a mixed water-surface layer containing surfactant and surface-active components in the potato medium. Surface tension reduction does not correlate well with antifoam performance enhancement. A model is proposed where surfactant adsorption promotes desorption of surface-active potato medium components from the water surface. At the SCAFC, desorption is not complete, yet the rate of bubble rupture is sufficiently enhanced to provide excellent foam control.

  4. Adsorption of mixed cationic-nonionic surfactant and its effect on bentonite structure.

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    Zhang, Yaxin; Zhao, Yan; Zhu, Yong; Wu, Huayong; Wang, Hongtao; Lu, Wenjing

    2012-01-01

    The adsorption of cationic-nonionic mixed surfactant onto bentonite and its effect on bentonite structure were investigated. The objective was to improve the understanding of surfactant behavior on clay mineral for its possible use in remediation technologies of soil and groundwater contaminated by toxic organic compounds. The cationic surfactant used was hexadecylpyridinium bromide (HDPB), and the nonionic surfactant was Triton X-100 (TX100). Adsorption of TX100 was enhanced significantly by the addition of HDPB, but this enhancement decreased with an increase in the fraction of the cationic surfactant. Part of HDPB was replaced by TX100 which decreased the adsorption of HDPB. However, the total adsorbed amount of the mixed surfactant was still increased substantially, indicating the synergistic effect between the cationic and nonionic surfactants. The surfactant-modified bentonite was characterized by Brunauer-Emmett-Teller specific surface area measurement, Fourier transform infrared spectroscopy, and thermogravimetric-derivative thermogravimetric/differential thermal analyses. Surfactant intercalation was found to decrease the bentonite specific surface area, pore volume, and surface roughness and irregularities, as calculated by nitrogen adsorption-desorption isotherms. The co-adsorption of the cationic and nonionic surfactants increased the ordering conformation of the adsorbed surfactants on bentonite, but decreased the thermal stability of the organobentonite system.

  5. Effects of Oscillatory Shear on the Orientation of the Inverse Bicontinuous Cubic Phase in a Nonionic Surfactant/Water System.

    Science.gov (United States)

    Yamanoi, Mutsumi; Kawabata, Youhei; Kato, Tadashi

    2016-03-29

    The bicontinuous inverse cubic phase (V2 phase) formed in amphiphilic systems consists of bilayer networks with a long-range order. We have investigated effects of oscillatory shear on the orientation of the V2 phase with space group Ia3d formed in a nonionic surfactant (C12E2)/water system by using simultaneous measurements of rheology/small-angle X-ray scattering. It is shown that grain refining occurs by applying the large amplitude oscillatory shear (LAOS) with a strain amplitude (γ0) of ∼20, which gives the ratio of the loss modulus (G″) to the storage modulus (G') (G″/G' = tan δ) of ∼100. On the other hand, orientation of the cubic lattice occurs when the small amplitude (γ0 ≈ 0.0004) oscillatory shear (SAOS) in the linear regime is applied to the sample just after the LAOS. Interestingly, the orientation is strongly enhanced by the "medium amplitude" (γ0 ≈ 0.05) oscillatory shear ("MAOS") after the SAOS. When the MAOS is applied before applying the LAOS, orientation to a particular direction is not observed, indicating that the grain refining process by the LAOS is necessary for the orientation during the MAOS. The results of additional experiments show that the shear sequence "LAOS-MAOS" is effective for the orientation of the cubic lattice. When the LAOS and MAOS are applied to the sample alternatively, grain refining and orientation occur during the LAOS and MAOS, respectively, indicating reversibility of the orientation. It is shown that (i) the degree of the orientation is dependent on γ0 and the frequency (ω) of the MAOS and (ii) relatively higher orientation can be obtained for the combination of γ0 and ω, which gives tan δ = 2-3. The lattice constant does not change throughout all the shearing processes and is equal to that before shearing within the experimental errors, indicating that the shear melting does not occur. These results suggest a possibility to control the orientation of the cubic lattice only by changing the

  6. Studies on the Cloud Points of Nonionic Surfactants with QSPR

    Institute of Scientific and Technical Information of China (English)

    CHEN Mei-ling; WANG Zheng-wu; ZHANG Ge-xin; GU Jin; CUN Zhe; TAO Fu-ming

    2007-01-01

    With quantum chemical parameters, topological indexes, and physical ehemistry parameters as descriptors, a quantitative structure-property relationship(QSPR) has been found for the cloud points of four series of nonionic surfactants(a total of 65 surfactants). The best-regressed model includes six descriptors, and the correlation coefficient of multiple determination is as high as 0. 962.

  7. Complex phase behavior in solvent-free nonionic surfactants

    DEFF Research Database (Denmark)

    Hillmyer, M.A.; Bates, F.S.; Almdal, K.

    1996-01-01

    Unsolvated block copolymers and surfactant solutions are ''soft materials'' that share a common set of ordered microstructures, A set of polyethyleneoxide-polyethylethylene (PEG-PEE) block copolymers that are chemically similar to the well-known alkane-oxyethylene (C(n)EO(m)) nonionic surfactants...... was synthesized here. The general phase behavior in these materials resembles that of both higher molecular weight block copolymers and lower molecular weight nonionic surfactant solutions. Two of the block copolymers exhibited thermally induced order-order transitions and were studied in detail by small...

  8. Adsorption of mixed cationic-nonionic surfactant and its effect on bentonite structure

    Institute of Scientific and Technical Information of China (English)

    Yaxin Zhang; Yan Zhao; Yong Zhu; Huayong Wu; Hongtao Wang; Wenjing Lu

    2012-01-01

    The adsorption of cationic-nordonic mixed surfactant onto bentonite and its effect on bentonite structure were investigated.The objective was to improve the understanding of surfactant behavior on clay mineral for its possible use in remediation technologies of soil and groundwater contaminated by toxic organic compounds.The cationic surfactant used was hexadecylpyridinium bromide(HDPB),and the nonionic suffactant was Triton X-100(TX100).Adsorption of TX100 was enhanced significantly by the addition of HDPB,but this enhancement decreased with an increase in the fraction of the cationic surfactant.Part of HDPB was replaced by TX100 which decreased the adsorption of HDPB.However,the total adsorbed amount of the mixed surfactant was still increased substantially,indicating the synergistic effect between the cationic and nonionic surfactants.The surfactant-modified bentonite was characterized by Brunauer-Emmett-Teller specific surface area measurement,Fourier transform infrared spectroscopy,and thermogravimetric-derivative thermogravimetric/differential thermal analyses.Surfactant intercalation was found to decrease the bentonite specific surface area,pore volume,and surface roughness and irregularities,as calculated by nitrogen adsorption-desorption isotherms.The co-adsorption of the cationic and nonionic surfactants increased the ordering conformation of the adsorbed surfactants on bentonite,but decreased the thermal stability of the organobentonite system.

  9. Studies on the electrocapillary curves of anionic surfactants in presence of non-ionic surfactants.

    Science.gov (United States)

    Bembi, R; Goyal, R N; Malik, W U

    1976-09-01

    Polyoxyethylated non-ionic surfactants such as Tween 20, Tween 40, Nonidet P40 and Nonex 501 have been supposed to be associated with cationic characteristics. Studies on the effect of these surfactants on the electrocapillary curves of the anionic surfactants Aerosol IB, Manaxol OT and sodium lauryl sulphate (SLS), show that the electrocapillary maxima shift towards positive potentials. The order of adsorption of the anionic surfactants is SLS > Manaxol OT > Aerosol IB while the shift in maxima is in the order Aerosol IB ~ Manaxol OT > SLS which confirms association of cationic characteristics with the micelles of these non-ionic surfactants. The magnitude of the shift in electrocapillary maxima is Nonex 501 > Nonidet P40 > Tween 20 > Tween 40 which may be the order of magnitude of the positive charge carried by these non-ionic surfactants.

  10. Nonionic surfactant Brij35 effects on toluene biodegradation in a ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... African Journal of Biotechnology Vol. 8 (20), pp. ... Nonionic surfactant effects on the toluene dissolved in the water phase and biodegradation kinetic behaviors .... Peat (industrial grade from KekkilaOyj, Tuusula, Finland) was dried at 105°C ... sludge obtained from the wastewater treatment plant in Hsinchu.

  11. Influence of Nonionic Surfactant Addition on Drag Reduction of Water Based Nanofluid in a Small Diameter Pipe

    Institute of Scientific and Technical Information of China (English)

    Micha(l) Drzazga; Andrzej Gierczycki; Grzegorz Dzido; Marcin Lemanowicz

    2013-01-01

    The goal of this research was to determine the impact of nonionic surfactants on drag reduction effect in water and metal oxide nanofluid.Two nonionic surfactants (Rokacet O7 and Rokanol K7) and copper(Ⅱ) oxide water-based nanofluid were examined.Friction factors in a 4 mm diameter pipe for the Reynolds number between 8000 and 50000 were determined.Results showed that addition of nonionic surfactants caused the decrease of friction factor in water and nanofluid.The drag reduction effect was similar in both cases.Presence of nanoparticles in the system has no great influence on drag reduction effect.

  12. Surface active properties and biological activity of novel nonionic surfactants containing pyrimidines and related nitrogen heterocyclic ring systems

    Directory of Open Access Journals (Sweden)

    El-Sayed, R.

    2008-06-01

    Full Text Available A series of annelated pyrimidine derivatives has been synthesized via different heterocyclization reactions of suitably functionalized 6-(4-octadecyloxyphenyl-4-oxo-2- thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile (4 with different electrophiles and nucleophiles. These heterocycles bear an active hydrogen atom (NH, OH or COOH which could be propoxylated using propylene oxide with different moles, 5, 10 and 15, to produce nonionic surfactant having a long alkyl chain with molecular weight suitable for becoming an amphiphilic molecule with correct hydrophilic-lypophilic balance which enhances solubility, biodegradability and hence lowers the toxicity to human beings and becomes environmentally friendly. In addition, the antimicrobial activities of these compounds were screened and it was found that some of these compounds have similar or higher activity compared with commercial antibiotic drugs (sulphadiazine, which make them suitable for diverse applications like the manufacturing of drugs, pesticides, emulsifiers, cosmetics, etc.Una serie de derivados pirimidínicos y relacionados han sido preparados vía diferentes reacciones de formación de heterociclos entre 6-(4-octadeciloxifenil-4-oxo-2-tioxo- 1,2,3,4-tetrahidropirimidina-5-carbonitrilo (4 y diferentes electrófilos y nucleófilos. Estos heterociclos tienen un átomo de hidrógeno activo (NH, OH, o COOH que fue propoxilado con diferentes moles de óxido de propileno (5, 10, o 15 para producir surfactantes no iónicos con una cadena alquílica larga y peso molecular apropiado para convertirse en una molécula anfifílica con un balance hidrofílico-lipofílico correcto que aumenta la solubilidad y la biodedradabilidad, decrece la toxicidad a los seres humanos, y se convierte en respetuoso con el medio ambiente. Además, las actividades antimicrobianas de estos compuestos fueron determinadas y se encontró que algunos de estos compuestos tuvieron una actividad similar o más alta que

  13. Enhanced desorption of phenanthrene from contaminated soil using anionic/nonionic mixed surfactant.

    Science.gov (United States)

    Zhou, Wenjun; Zhu, Lizhong

    2007-05-01

    A new approach using an anionic/nonionic mixed surfactant, sodium dodecyl sulphate (SDS) with Triton X-100 (TX100), was utilized for the desorption of phenanthrene from an artificial contaminated natural soil in an aim to improve the efficiency of surfactant remediation technology. The experimental results showed that the presence of SDS not only reduced the sorption of TX100 onto the natural soil, but also enhanced the solubilization of TX100 for phenanthrene, both of which resulted in the distribution of phenanthrene in soil-water systems decreasing with increasing mole fraction of SDS in surfactant solutions. These results can be attributed to the formation of mixed micelles in surfactant solution and the corresponding decrease in the critical micelle concentration of TX100 in mixed solution. The batch desorption experiments showed that the desorption percentage of phenanthrene from the contaminated soil with mixed solution was greater than that with single TX100 solution and appeared to be positively related to the mole fraction of SDS in surfactant solution. Thus, the anionic/nonionic mixed surfactants are more effective for the desorption of phenanthrene from the contaminated soil than a single nonionic surfactant.

  14. Ecotoxicological characterization of polyoxyethylene glycerol ester non-ionic surfactants and their mixtures with anionic and non-ionic surfactants.

    Science.gov (United States)

    Ríos, Francisco; Fernández-Arteaga, Alejandro; Lechuga, Manuela; Fernández-Serrano, Mercedes

    2017-03-03

    This paper reports on a study that investigated the aquatic toxicity of new non-ionic surfactants derived from renewable raw materials, polyoxyethylene glycerol ester (PGE), and their binary mixtures with anionic and non-ionic surfactants. Toxicity of pure PGEs was determined using representative organisms from different trophic levels: luminescent bacteria (Vibrio fischeri), microalgae (Pseudokirchneriella subcapitata), and freshwater crustaceans (Daphnia magna). Relationships between toxicity and the structural parameters such as unit of ethylene oxide (EO) and hydrophilic-lipophilic balance (HLB) were evaluated. Critical micellar concentration (CMC) in the conditions of the toxicity test was also determined. It was found that the toxicity of the aqueous solutions of PGE decreased when the number of EO units in the molecule, HLB, and CMC increased. PGEs showed lower CMC in marine medium, and the toxicity to V. ficheri is lower when the CMC was higher. Given their non-polar nature, narcosis was expected to be the primary mode of toxic action of PGEs. For the mixture of surfactants, we observed that the mixtures with PGE that had the higher numbers of EO units were more toxic than the aqueous solutions of pure surfactants. Moreover, we found that concentration addition was the type of action more likely to occur for mixtures of PGE with lower numbers of EO units with non-ionic surfactants (alkylpolyglucoside and fatty alcohol ethoxylate), whereas for the mixture of PGE with lower EO units and anionic surfactant (ether carboxylic derivative), the most common response type was response addition. In case of mixtures involving amphoteric surfactants and PGEs with the higher numbers of EO units, no clear pattern with regard to the mixture toxicity response type could be observed.

  15. Immobilization of fungal laccase onto a nonionic surfactant-modified clay material: application to PAH degradation.

    Science.gov (United States)

    Chang, Yi-Tang; Lee, Jiunn-Fwu; Liu, Keng-Hua; Liao, Yi-Fen; Yang, Vivian

    2016-03-01

    Nonionic surfactant-modified clay is a useful absorbent material that effectively removes hydrophobic organic compounds from soil/groundwater. We developed a novel material by applying an immobilized fungal laccase onto nonionic surfactant-modified clay. Low-water-solubility polycyclic aromatic hydrocarbons (PAHs) (naphthalene/phenanthrene) were degraded in the presence of this bioactive material. PAH degradation by free laccase was higher than degradation by immobilized laccase when the surfactant concentration was allowed to form micelles. PAH degradation by immobilized laccase on TX-100-modified clay was higher than on Brij35-modified clay. Strong laccase degradation of PAH can be maintained by adding surfactant monomers or micelles. The physical adsorption of nonionic surfactants onto clay plays an important role in PAH degradation by laccase, which can be explained by the structure and molecular interactions of the surfactant with the clay and enzyme. A system where laccase is immobilized onto TX-100-monomer-modified clay is a good candidate bioactive material for in situ PAHs bioremediation.

  16. Perstraction of intracellular pigments by submerged cultivation of Monascus in nonionic surfactant micelle aqueous solution.

    Science.gov (United States)

    Hu, Zhiqiang; Zhang, Xuehong; Wu, Zhenqiang; Qi, Hanshi; Wang, Zhilong

    2012-04-01

    "Milking processing" describes the cultivation of microalgae in a water-organic solvent two-phase system that consists of simultaneous fermentation and secretion of intracellular product. It is usually limited by the conflict between the biocompatibility of the organic solvent to the microorganisms and the ability of the organic solvent to secret intracellular product into its extracellular broth. In the present work, submerged cultivation of Monascus in the nonionic surfactant Triton X-100 micelle aqueous solution for pigment production is exploited, in which the fungus Monascus remains actively growing. Permeabilization of intracellular pigments across the cell membrane and extraction of the pigments to the nonionic surfactant micelles of its fermentation broth occur simultaneously. "Milking" the intracellular pigments in the submerged cultivation of Monascus is a perstraction process. The perstractive fermentation of intracellular pigments has the advantage of submerged cultivation by secretion of the intracellular pigments to its extracellular broth and the benefit of extractive microbial fermentation by solubilizing the pigments into nonionic surfactant micelles. It is shown as the marked increase of the extracellular pigment concentration by the submerged cultivation of Monascus in the nonionic surfactant Triton X-100 micelle solution.

  17. Release of salicylic acid, diclofenac acid and diclofenac acid salts from isotropic and anisotropic nonionic surfactant systems across rat skin.

    Science.gov (United States)

    Gabboun, N H; Najib, N M; Ibrahim, H G; Assaf, S

    2001-01-01

    Release of salicylic acid, diclofenac acid, diclofenac diethylamine and diclofenac sodium, from lyotropic structured systems, namely; neat and middle liquid crystalline phases, across mid-dorsal hairless rat skin into aqueous buffer were studied. Release results were compared with those from the isotropic systems. The donor systems composed of the surfactant polyoxyethylene (20) isohexadecyl ether, HCl buffer of pH 1 or distilled water and the specific drug. High performance liquid chromatography (HPLC) methods were used to monitor the transfer of the drugs across the skin barrier. Results indicated that the rate-determining step in the transport process was the release of the drug from the specified donor system. Further, apparent zero order release was demonstrated with all systems. Except for diclofenac sodium, drug fluxes decreased as the donor medium changed from isotropic to anisotropic. The decrease in fluxes was probably due to the added constrains on the movement of drug molecules. By changing the anisotropic donor medium from neat to middle phase, drug flux decreased in case of salicylic acid and diclofenac sodium. In the mean time, flux increased in case of the diethylamine salt and appeared nearly similar in case of diclofenac acid. Rates of drug transfer across the skin from the anisotropic donors seemed to be largely controlled by the entropy contribution to the transport process. The type and extent of drug-liquid crystal interactions probably influenced the latter.

  18. STUDY ON NEUTRAL DEINKING OF ONP WITH NON-IONIC SURFACTANTS

    Institute of Scientific and Technical Information of China (English)

    Qingxian Miao; Shoujuan Wang; Menghua Qin; Yingjuan Fu

    2004-01-01

    The ONP neutral deinking performances of fatty alcohol polyoxyethylene ether with different EO value were investigated in this paper. Meanwhile, the synergistic effects of different non-ionic surfactants,the co-operation of non-ionic surfactants with anionic surfactants, and the effects of different salts added into the above two systems on deinkability were also studied. The results showed the deinking performance of A7 was good. But the synergistic effect of A7 and A4 was better. In addition, the accession of salt W2 could improve the deinking efficiency, and the brightness of the deinked pulp was 1.0%ISO higher than that of A7 and A4.

  19. Formulation design and characterization of a non-ionic surfactant based vesicular system for the sustained delivery of a new chondroprotective agent

    Directory of Open Access Journals (Sweden)

    Muhammad Imran Khan

    2015-09-01

    Full Text Available Diacerein is used for symptomatic relief and cartilage regeneration in osteoarthritis. Due to gastrointestinal side effects, poor aqueous solubility and low bioavailability, its clinical usage has been restricted. The objective of the present study was to enhance its dissolution profile and to attain sustained release by designing a novel delivery system based on niosomes. Five niosomal formulations (F1-F5 with non-ionic surfactant (sorbitan monostearate and cholesterol in varying ratios of 5:5, 6:4, 7:3, 8:2 and 9:1 were developed by the reverse-phase evaporation technique. The size and polydispersivity index (PDI were found in the range of 0.608 µm to 1.010 µm and 0.409 to 0.781, respectively. Scanning electron microscopy (SEM of the selected formulation (F3 revealed spherical vesicles, and 79.8% entrapment was achieved with F3 (7:3. Dissolution studies using the dialysis method showed sustained release behaviour for all formulations. The optimized surfactant-to-cholesterol concentration (7:3 in formulation F3sustained the drug-release time (T50% up to 10 hours. Kinetic modelling exhibited a zero-order release (R2=0.9834 and the release exponent 'n' of the Korsmayer-Peppas model (n=0.90 confirmed non-fickian and anomalous release. The results of this study suggest that diacerein can be successfully entrapped into niosomes using sorbitan monostearate and that these niosomes have the potential to deliver diacerein efficiently at the absorption site.

  20. Investigation of crude oil-water emulsions in presence of non-ionic surfactants. I. Behavior of emulsions at room temperature and in ion-free systems

    Energy Technology Data Exchange (ETDEWEB)

    Felian, B.; Balazs, J.; Lakatos, I.

    1983-01-01

    The investigations were aimed at determination of the emulsion-forming ability of surface-active agents suitable for oil displacement, and within this, the effects of the type and relative quantity of the tensides and of the phase ratio on the properties of the emulsions. Crude oil was used, with 4-ethoxy-nonylphenolsulphonate as the anionic tenside, and nonylphenols with different ethoxy group numbers as the non-ionic ones. From the experimental results it was concluded that stable and high-viscosity oil-external emulsions were formed in the system free of tensides. With increasing concentration of surfactants having low HLB values, the plastic viscosity of the emulsions decreased, while at a characteristic concentration phase inversion took place. With tensides having high HLB values, similar changes in rheological properties occurred, but phase inversion was not observed. This anomalous behavior of the emulsions is attributed to the interaction of the synthetic and natural surface-active agents present inthe crude oil. 19 references, 10 figures, 1 table.

  1. Solubilization capacity of nonionic surfactant micelles exhibiting strong influence on export of intracellular pigments in Monascus fermentation

    Science.gov (United States)

    Kang, Biyu; Zhang, Xuehong; Wu, Zhenqiang; Qi, Hanshi; Wang, Zhilong

    2013-01-01

    Summary In this study, perstractive fermentation of intracellular Monascus pigments in nonionic surfactant micelle aqueous solution had been studied. The permeability of cell membrane modified by nonionic surfactant might have influence on the rate of export of intracellular pigments into its extracellular broth while nearly no effect on the final extracellular pigment concentration. However, the solubilization of pigments in nonionic surfactant micelles strongly affected the final extracellular pigment concentration. The solubilization capacity of micelles depended on the kind of nonionic surfactant, the super-molecule assembly structure of nonionic surfactant in an aqueous solution, and the nonionic surfactant concentration. Elimination of pigment degradation by export of intracellular Monascus pigments and solubilizing them into nonionic surfactant micelles was also confirmed experimentally. Thus, nonionic surfactant micelle aqueous solution is potential for replacement of organic solvent for perstractive fermentation of intracellular product. PMID:23425092

  2. Solubilization capacity of nonionic surfactant micelles exhibiting strong influence on export of intracellular pigments in Monascus fermentation.

    Science.gov (United States)

    Kang, Biyu; Zhang, Xuehong; Wu, Zhenqiang; Qi, Hanshi; Wang, Zhilong

    2013-09-01

    In this study, perstractive fermentation of intracellular Monascus pigments in nonionic surfactant micelle aqueous solution had been studied. The permeability of cell membrane modified by nonionic surfactant might have influence on the rate of export of intracellular pigments into its extracellular broth while nearly no effect on the final extracellular pigment concentration. However, the solubilization of pigments in nonionic surfactant micelles strongly affected the final extracellular pigment concentration. The solubilization capacity of micelles depended on the kind of nonionic surfactant, the super-molecule assembly structure of nonionic surfactant in an aqueous solution, and the nonionic surfactant concentration. Elimination of pigment degradation by export of intracellular Monascus pigments and solubilizing them into nonionic surfactant micelles was also confirmed experimentally. Thus, nonionic surfactant micelle aqueous solution is potential for replacement of organic solvent for perstractive fermentation of intracellular product.

  3. Impact of non-ionic surfactant chemical structure on morphology and stability of polystyrene nanocomposite latex

    CSIR Research Space (South Africa)

    Greesh, N

    2016-01-01

    Full Text Available Polystyrene (PS) colloid particles in presence of non-ionic surfactant-modified clay particles were prepared by the free-radical polymerization of styrene monomers in emulsion. Three different types of non-ionic surfactants, sorbitan monopalmitate...

  4. Thermodynamics of non-ionic surfactant Triton X-100-cationic surfactants mixtures at the cloud point

    Energy Technology Data Exchange (ETDEWEB)

    Batigoec, Cigdem [Department of Chemistry, Faculty of Sciences, Trakya University, 22030 Edirne (Turkey); Akbas, Halide, E-mail: hakbas34@yahoo.com [Department of Chemistry, Faculty of Sciences, Trakya University, 22030 Edirne (Turkey); Boz, Mesut [Department of Chemistry, Faculty of Sciences, Trakya University, 22030 Edirne (Turkey)

    2011-12-15

    Highlights: > Non-ionic surfactants are used as emulsifier and solubilizate in such as textile, detergent and cosmetic. > Non-ionic surfactants occur phase separation at temperature as named the cloud point in solution. > Dimeric surfactants have attracted increasing attention due to their superior surface activity. > The positive values of {Delta}G{sub cp}{sup 0} indicate that the process proceeds nonspontaneous. - Abstract: This study investigates the effects of gemini and conventional cationic surfactants on the cloud point (CP) of the non-ionic surfactant Triton X-100 (TX-100) in aqueous solutions. Instead of visual observation, a spectrophotometer was used for measurement of the cloud point temperatures. The thermodynamic parameters of these mixtures were calculated at different cationic surfactant concentrations. The gemini surfactants of the alkanediyl-{alpha}-{omega}-bis (alkyldimethylammonium) dibromide type, on the one hand, with different alkyl groups containing m carbon atoms and an ethanediyl spacer, referred to as 'm-2-m' (m = 10, 12, and 16) and, on the other hand, with -C{sub 16} alkyl groups and different spacers containing s carbon atoms, referred to as '16-s-16' (s = 6 and 10) were synthesized, purified and characterized. Additions of the cationic surfactants to the TX-100 solution increased the cloud point temperature of the TX-100 solution. It was accepted that the solubility of non-ionic surfactant containing polyoxyethylene (POE) hydrophilic chain was a maximum at the cloud point so that the thermodynamic parameters were calculated at this temperature. The results showed that the standard Gibbs free energy ({Delta}G{sub cp}{sup 0}), the enthalpy ({Delta}H{sub cp}{sup 0}) and the entropy ({Delta}S{sub cp}{sup 0}) of the clouding phenomenon were found positive in all cases. The standard free energy ({Delta}G{sub cp}{sup 0}) increased with increasing hydrophobic alkyl chain for both gemini and conventional cationic

  5. Structure and Dynamics of Nonionic Surfactant Aggregates in Layered Materials.

    Science.gov (United States)

    Guégan, Régis; Veron, Emmanuel; Le Forestier, Lydie; Ogawa, Makoto; Cadars, Sylvian

    2017-09-26

    The aggregation of surfactants on solid surfaces as they are adsorbed from solution is the basis of numerous technological applications such as colloidal stabilization, ore flotation, and floor cleaning. The understanding of both the structure and the dynamics of surfactant aggregates applies to the development of alternative ways of preparing hybrid layered materials. For this purpose, we study the adsorption of the triethylene glycol mono n-decyl ether (C10E3) nonionic surfactant onto a synthetic montmorillonite (Mt), an aluminosilicate clay mineral for organoclay preparation with important applications in materials sciences, catalysis, wastewater treatment, or as drug delivery. The aggregation mechanisms follow those observed in an analogous natural Mt, with the condensation of C10E3 in a bilayer arrangement once the surfactant self-assembles in a lamellar phase beyond the critical micelle concentration, underlining the importance of the surfactant state in solution. Solid-state (1)H nuclear magnetic resonance (NMR) at fast magic-angle spinning (MAS) and high magnetic field combined with(1)H-(13)C correlation experiments and different types of (13)C NMR experiments selectively probes mobile or rigid moieties of C10E3 in three different aggregate organizations: (i) a lateral monolayer, (ii) a lateral bilayer, and (iii) a normal bilayer. High-resolution (1)H{(27)Al} CP-(1)H-(1)H spin diffusion experiments shed light on the proximities and dynamics of the different fragments and fractions of the intercalated surfactant molecules with respect to the Mt surface. (23)Na and (1)H NMR measurements combined with complementary NMR data, at both molecular and nanometer scales, precisely pointed out the location of the C10E3 ethylene oxide hydrophilic group in close contact with the Mt surface interacting through ion-dipole or van der Waals interactions.

  6. Synthesis of high quality MCM-48 with binary cationic-nonionic surfactants.

    Science.gov (United States)

    Zhao, Wei; Li, Quanzhi; Wang, Lina; Chu, Jinglong; Qu, Jinkui; Li, Shaohua; Qi, Tao

    2010-05-18

    Highly ordered MCM-48 was synthesized in the hydrothermal system of a mixture of cationic cetyltrimethylammonium bromide (CTAB) and nonionic poly(ethylene glycol) monooctylphenyl ether (Tx-100) using water glass as the silicon source. The effect of various factors, such as the amount of surfactant, CTAB/Tx-100, Si source, crystallization temperature, and crystallization time, on the synthesis were discussed in detail. The local effective surfactant packing parameter theory and the charge balance theory were used to explain the reason that various factors can affect the product structure reasonably. Especially, the role of Tx-100 was expounded. The optimum synthesis conditions for MCM-48 were obtained.

  7. Nanostructured fluids from degradable nonionic surfactants for the cleaning of works of art from polymer contaminants.

    Science.gov (United States)

    Baglioni, M; Raudino, M; Berti, D; Keiderling, U; Bordes, R; Holmberg, K; Baglioni, P

    2014-09-21

    Nanostructured fluids containing anionic surfactants are among the best performing systems for the cleaning of works of art. Though efficient, their application may result in the formation of a precipitate, due to the combination with divalent cations that might leach out from the artifact. We propose here two new aqueous formulations based on nonionic surfactants, which are non-toxic, readily biodegradable and insensitive to the presence of divalent ions. The cleaning properties of water-nonionic surfactant-2-butanone (MEK) were assessed both on model surfaces and on a XIII century fresco that could not be cleaned using conventional methods. Structural information on nanofluids has been gathered by means of small-angle neutron scattering, dynamic light scattering and nuclear magnetic resonance with diffusion monitoring. Beside the above-mentioned advantages, these formulations turned out to be considerably more efficient in the removal of polymer coatings than those based on anionic surfactants. Our results indicate that the cleaning process most likely consists of two steps: initially, the polymer film is swollen by the MEK dissolved in the continuous domain of the nanofluid; in the second stage, surfactant aggregates come into play by promoting the removal of the polymer film with a detergency-like mechanism. The efficiency can be tuned by the composition and nature of amphiphiles and is promoted by working as close as possible to the cloud point of the formulation, where the second step proceeds at maximum rate.

  8. Stabilization of human papillomavirus virus-like particles by non-ionic surfactants.

    Science.gov (United States)

    Shi, Li; Sanyal, Gautam; Ni, Alex; Luo, Zheng; Doshna, Sarah; Wang, Bei; Graham, Tammy L; Wang, Ning; Volkin, David B

    2005-07-01

    Human papillomavirus (HPV) virus-like-particles (VLPs) produced by recombinant expression systems are promising vaccine candidates for prevention of cervical cancers as well as genital warts. At high protein concentrations, HPV VLPs, comprised of the viral capsid protein L1 and expressed and purified from yeast, are protected against detectable aggregation during preparation and storage by high concentrations of NaCl. At low protein concentrations, however, high salt concentration alone does not fully protect HPV VLPs from aggregation. Moreover, the analytical analysis of HPV VLPs proved to be a challenge due to surface adsorption of HPV VLPs to storage containers and cuvettes. The introduction of non-ionic surfactants into HPV VLP aqueous solutions provides significantly enhanced stabilization of HPV VLPs against aggregation upon exposure to low salt and protein concentration, as well as protection against surface adsorption and aggregation due to heat stress and physical agitation. The mechanism of non-ionic surfactant stabilization of HPV VLPs was extensively studied using polysorbate 80 (PS80) as a representative non-ionic surfactant. The results suggest that PS80 stabilizes HPV VLPs mainly by competing with the VLPs for various container surfaces and air/water interfaces. No appreciable binding of PS80 to intact HPV VLPs was observed although PS80 does bind to the denatured HPV L1 protein. Even in the presence of stabilizing level of PS80, however, an ionic strength dependence of HPV VLP stabilization against aggregation is observed indicating optimization of both salt and non-ionic surfactant levels is required for effective stabilization of HPV VLPs in solution. (c) 2005 Wiley-Liss, Inc.

  9. Effect of anionic-nonionic mixed surfactant on ryegrass uptake of phenanthrene and pyrene from water

    Institute of Scientific and Technical Information of China (English)

    SUN Lu; ZHU LiZhong

    2009-01-01

    The effect of anionic-nonionic mixed surfactant (SDBS-TX100) on the uptake of phenanthrene and pyrene by ryegrass in a hydroponic system was studied, and the influence factors including the com-positions and concentrations of mixed surfactants and the compounds properties were also discussed. The results showed that SDBS-TX100 mixtures with certain compositions and concentrations could enhance the uptake of phenanthrene and pyrene by ryegrass, which could be attributed to the im-proved uptake capacity of ryegrass roots for phenanthrene and pyrene. SDBS-TX100 can enhance the uptake of phenanthrene and pyrene by ryegrass in a wider range of surfactant concentrations (0-0.8 mmol/L) in comparison with corresponding single surfactants, and the maximal contents of phenan-threne and pyrene in ryegrass roots were obtained with the concentrations of SDBS-TX100 around the corresponding critical micelle concentrations. The uptake of phenanthrene and pyrene by ryegrass increased with the increasing mole fraction of SDBS in mixed surfactant solutions, and SDBS-TX100 mixture with a mole ratio of SDBS to TX100 at 9:1 had the greatest capacity in enhancing the uptake of phenanthrene and pyrene, at which the corresponding maximal concentrations of phenanthrene and pyrene in ryegrass roots were 216 and 8.16 times those without surfactants, respectively. Results from this study indicate that the anionic-nonionic mixed surfactants (SDBS-TX100) would be a preferred selection for the application of surfactant-enhanced phytoremediation technology to contaminated soils.

  10. The synthesis and properties of a new nonionic Gemini surfactant

    Science.gov (United States)

    Ren, Yanmei; Lv, Tong; Wang, Qi; Tian, Zhenxing

    2010-07-01

    A new Gemini nonionic surfactant was prepared, taking anhydrous glucose, glycol, maleic anhydride, lauric acid as main materials, and the reaction was carried out by three steps. Firstly, glycol glucoside was synthesized by the direct glycosidation of the anhydrous glucose with glycol in the presence of acidic catalyst. The synthesis and the characterization of this have been reported previously.Secondly, reaction intermediate was prepared by ring opening reaction of maleic anhydride with glycol glucoside. The last, primary hydroxyl group in glucose of reaction intermediate was esterified with lauric acid for synthesis of target product. It was analyzed and characterized by IR, 1HNMR and 13CNMR. Besides, the critical micelle concentration (cmc) and the corresponding surface tension of the target product were measured to be 8.87×10-3molL-1 and 20.70mNm-1 (20°C), respectively.

  11. Development and Characterization of Non-Ionic Surfactant Vesicles (Niosomes for Oral delivery of Lornoxicam

    Directory of Open Access Journals (Sweden)

    K B Bini

    2012-09-01

    Full Text Available Niosomes are non-ionic surfactant vesicles obtained on hydration of synthetic nonionic surfactants, with or without incorporation of cholesterol or other lipids. They are vesicular systems similar to liposomes that can be used as carriers of amphiphilic and lipophilic drugs. Niosomes are promising vehicle for drug delivery and being non-ionic, it is less toxic and improves the therapeutic index of drug by restricting its action to target cells. They are lamellar structures that are microscopic in size. They are now widely used as alternative to liposomes. Niosomal dispersion in an aqueous phase can be emulsified in a non-aqueous phase to regulate the delivery rate of drug and administer normal vesicle in external non-aqueous phase. Stable niosome dispersion must exhibit a constant particle size and a constant level of entrapped drug. Span 60 is the better surfactant of all because it is having high phase transition temperature and low HLB (Hydrophilic Lipophilic Balance so it will form vesicles of good size.one more reason for the selection of span 60 and that was the critical packing factor which is between 0.5 and 1 for this surfactant so it forms spherical vesicles. If CPP factor is below 0.5 it cause micelles to form and if it was above 1 it will form inverted vesicles. Lornoxicam loaded niosomes were prepared by Lipid film hydration method with different surfactant to cholesterol ratio. The niosome formulations were evaluated for FT-IR study,microscopy. The niosomal suspensions were further evaluated for entrapment efficiency, In vitro release study, Kinetic data analysis, Stability study. The formulation F4 which showed higher entrapment efficiency of 80.54 ±0.99. Release was best explained by the zero order kinetics. Kinetic analysis shows that the drug release follows super case II transport diffusion. Niosome formulation has showed appropriate stability for 90 days.

  12. Formation of macroporous gel morphology by phase separation in the silica sol-gel system containing nonionic surfactant

    Institute of Scientific and Technical Information of China (English)

    Junsheng Wu; Xiaogang Li; Wei Du; Hua Chen

    2005-01-01

    The phase separation and gel formation behavior in an alkoxy-derived silica sol-gel system containing Ci6EOi5 has been investigated. Various gel morphologies similar to other sol-gel systems containing organic additives were obtained by changing the preparation conditions. Micrometer-range interconnected porous gels were obtained by freezing transitional structures of phase separation in the sol-gel process. The dependence of the resulting gel morphology on several important reaction parameters such as the starting composition, reaction temperature and acid catalyst concentration was studied in detail. The experimental results indicate that the gel morphology is mainly determined by the time relation between the onset of phase separation and gel formation.

  13. A study of correlations between the release of drugs from petrolatum-based gels containing nonionic surfactants and some physical and physico-chemical characteristics of the gel systems.

    Science.gov (United States)

    Colo, G D; Nannipieri, E; Serafini, M F; Vitale, D

    1986-06-01

    Synopsis The in vitro release of benzocaine and 2-ethyIhexyl p-di-methylaminobenzoate (EH-PABA) from petrolatum-based gels either containing two nonionic surfactants, or not, was compared with some physical and/or physico-chemical characteristics of the drugs, the gels and the drug-gel systems. The surfactants had no effect on the release of EH-PABA, the less polar drug, whereas they decreased the release of benzocaine. Moreover, the release data show a complex dependence of diffusive properties of ben-zocaine on drug and surfactant concentration. Benzocaine appears to form mixed micelles with each of the two surfactants and/or undergoes self-aggregation phenomena within surfactant micelles. The results indicate that drug diffusion is influenced by gel porosity, drug molecular size and polarity and molecular interactions. Etude des corrélations entre la disponibilité des medicaments dans les gels a base de vaseline contenant des surfactifs non ioniques et quelques propriétés physiques et physicochimiques des gels.

  14. Novel designed polyoxyethylene nonionic surfactant with improved safety and efficiency for anticancer drug delivery

    Directory of Open Access Journals (Sweden)

    Li C

    2014-04-01

    Full Text Available Chang Li,1 Chunmeng Sun,1 Shasha Li,1 Peng Han,2 Huimin Sun,3 Ammar Ouahab,1 Yan Shen,1 Yourui Xu,1 Yerong Xiong,1 Jiasheng Tu11State Key Laboratory of Natural Medicines, Department of Pharmaceutics, China Pharmaceutical University, Nanjing, 2Chinese Pharmacopoeia Commission, Beijing, 3National Institute for Food and Drug Control, Beijing, People's Republic of ChinaAbstract: In order to limit the adverse reactions caused by polysorbate 80 in Taxotere®, a widely used formulation of docetaxel, a safe and effective nanocarrier for this drug has been developed based on micelles formed by a new class of well-defined polyoxyethylene sorbitol oleate (PSO with sorbitol as the matrix in aqueous solution. The physicochemical properties of the amphiphilic surfactant and the resulting micelles can be easily fine-tuned by the homogeneous sorbitol matrix and pure oleic acid. Composition, critical micelle concentration, and entrapment efficiency were investigated by ultraviolet visible spectroscopy, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, fluorospectrophotometry, and high-performance liquid chromatography. In vitro and in vivo evaluation revealed that PSO had exceptionally low hemolysis and histamine release rates compared with commercial polysorbate 80. Moreover, the tumor targeting delivery of PSO was investigated by in vivo imaging in S180 tumor-bearing mice. The results suggest that this novel delivery system, PSO, provides an acceptable alternative to polysorbate 80 for delivery of docetaxel. Further, due to the hypoallergenic nature of PSO, the mechanism of pseudoallergy caused by the polyoxyethylene nonionic surfactant was investigated. Based on in vitro cell analysis, it was assumed that the initial contact of polyoxyethylene nonionic surfactant with mast cells provoked pseudoallergy via polyamine receptor-mediated endocytosis.Keywords: polyoxyethylene nonionic surfactant, sorbitol, isosorbide, pseudoallergy

  15. SOLUBILIZATION OF DODECANE, TETRACHLOROETHYLENE, AND 1,2-DICHLOROBENZENE IN MICELLAR SOLUTIONS OF ETHOXYLATED NONIONIC SURFACTANTS

    Science.gov (United States)

    Although surfactants have received considerable attention as a potential means for enhancing the recovery of organic compounds from the subsurface, only limited information is available regarding the micellar solubilization of common groundwater contaminants by nonionic surfactan...

  16. Stability of emulsion at the presence of polycomplexes based on polyacrilic and polymethacrilyc acids and nonionic surfactant OP-10

    Directory of Open Access Journals (Sweden)

    K. Omarova

    2012-12-01

    Full Text Available Stability of straight and reverse emulsions based on polyacrilic and polymethacrilyc acids and nonionic surfactant OP-10 was studied. Detergency of these polycomplexes on oil substrate covered on solid surfaces of different nature were considered. The results obtained allow explain the mechanism of exlusion of non-polar liquids from capillary-porous systems.

  17. Self-consistent field modeling of non-ionic surfactants at the silica-water interface: Incorporating molecular detail

    NARCIS (Netherlands)

    Postmus, B.R.; Leermakers, F.A.M.; Cohen Stuart, M.A.

    2008-01-01

    We have constructed a model to predict the properties of non-ionic (alkyl-ethylene oxide) (C(n)E(m)) surfactants, both in aqueous solutions and near a silica surface, based upon the self-consistent field theory using the Scheutjens-Fleer discretisation scheme. The system has the pH and the ionic

  18. Quantitative Structure-Property Relationship on Prediction of Surface Tension of Nonionic Surfactants

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A quantitative structure-property relationship (QSPR) study has been made for the prediction of the surface tension of nonionic surfactants in aqueous solution.The regressed model includes a topological descriptor,the Kier & Hall index of zero order (KH0) of the hydrophobic segment of surfactant and a quantum chemical one,the heat of formation () of surfactant molecules.The established general QSPR between the surface tension and the descriptors produces a correlation coefficient of multiple determination,=0.9877,for 30 studied nonionic surfactants.

  19. Interfacial aggregation of a nonionic surfactant: Effect on the stability of silica suspensions

    Energy Technology Data Exchange (ETDEWEB)

    Giordano-Palmino, F.; Denoyel, R.; Rouquerol, J. (CNRS, Marseille (France). Centre de thermodynamique et Microcalorimetrie)

    1994-06-01

    Nonionic surfactants are in widespread use in technological applications such as flotation, detergency, suspension stabilization (paints, ceramic preparation, pharmaceuticals, cosmetics), and enhanced oil recovery. The adsorption of the nonionic surfactant TX 100 in two silica suspensions (Ludox HS40 and Syton W30) has been studied with the aim of relating the structure of the adsorbed layer to the stability of the suspension. First, a thermodynamic study based on the determination of adsorption isotherms and displacement enthalpies as a function of pH and solid/liquid ratio was carried out and lead to the conclusion that such a surfactant forms micelle-like aggregates on the silica surface. Then, a stability study based on visual observation, turbidimetry, and particle size determination (by photon correlation spectroscopy) was performed in order to determine the TX 100 concentration range in which flocculation occurs. Considering that the surface is covered with micelle-like aggregates in the flocculation range and that the [zeta]-potential (determined by microelectrophoresis) has varied only slightly at the onset of flocculation, it is concluded that the flocculation mechanism is a bridging of particles by surface micelles. This bridging of particles by aggregates similar in size and shape could be an explanation of the presence, in such systems, of optimum flocculation at half surface coverage.

  20. Arsenic retention and transport behavior in the presence of typical anionic and nonionic surfactants.

    Science.gov (United States)

    Liang, Chuan; Wang, Xianliang; Peng, Xianjia

    2016-01-01

    The massive production and wide use of surfactants have resulted in a large amount of surfactant residuals being discharged into the environment, which could have an impact on arsenic behavior. In the present study, the influence of the anionic surfactant sodium dodecyl benzene sulfonate (SDBS) and nonionic surfactant polyethylene glycol octylphenyl ether (Triton X-100) on arsenic behavior was investigated in batch and column tests. The presence of SDBS and Triton X-100 reduced arsenic retention onto ferrihydrite (FH), enhanced arsenic transport through FH coated sand (FH-sand) columns and promoted arsenic release from the FH surface. With coexisting surfactants in solution, the equilibrium adsorbed amount of arsenic on FH decreased by up to 29.7% and the adsorption rate decreased by up to 52.3%. Pre-coating with surfactants caused a decrease in the adsorbed amount and adsorption rate of arsenic by up to 15.1% and 58.3%, respectively. Because of the adsorption attenuation caused by surfactants, breakthrough of As(V) and As(III) with SDBS in columns packed with FH-sand was 23.8% and 14.3% faster than that in those without SDBS, respectively. In columns packed with SDBS-coated FH-sand, transport of arsenic was enhanced to a greater extent. Breakthrough of As(V) and As(III) was 52.4% and 43.8% faster and the cumulative retention amount was 44.5% and 57.3% less than that in pure FH-sand column systems, respectively. Mobilization of arsenic by surfactants increased with the increase of the initial adsorbed amount of arsenic. The cumulative release amount of As(V) and As(III) from the packed column reached 10.8% and 36.0%, respectively.

  1. An Energetic Analysis of the Phase Separation in Non-Ionic Surfactant Mixtures: The Role of the Headgroup Structure

    Directory of Open Access Journals (Sweden)

    José Manuel Hierrezuelo

    2014-08-01

    Full Text Available The main goal of this paper was to examine the effect of the hydrophilic surfactant headgroup on the phase behavior of non-ionic surfactant mixtures. Four mixed systems composed of an ethoxylated plus sugar-based surfactants, each having the same hydrophobic tail, were investigated. We found that the hydrophilicity of the surfactant inhibits the tendency of the system to phase separate, which is sensitive to the presence of NaCl. Applying a classical phase separation thermodynamic model, the corresponding energy parameters were evaluated. In all cases, the parameters were found to depend on the type of nonionic surfactant, its concentration in the micellar solution and the presence of NaCl in the medium. The experimental results can be explained by assuming the phase separation process takes place as a result of reduced hydration of the surfactant headgroup caused by a temperature increase. The enthalpy-entropy compensation plot exhibits excellent linearity. We found that all the mixed surfactant systems coincided on the same straight line, the compensation temperature being lower in the presence of NaCl.

  2. Influence of nonionic surfactant on the solubilization and biodegradation of phenanthrene

    Institute of Scientific and Technical Information of China (English)

    YANG Jian-gang; LIU Xiang; LONG Tao; YU Gang; PENG She; ZHENG Liu

    2003-01-01

    Phenanthrene was solubilized in two different nonionic surfactants, Tween80 and Triton X-100. The bioavailability of phenanthrene to the bacteria isolated from the petroleum contaminated soils was studied based on the rotary flasks experiments. The results showed that the concentration of nonionic surfactants above the critical micelle concentration(CMC) can increase the solubility of phenanthrene in water and were innoxious to the phenanthrene-degrading bacteria; phenanthrene solubilized in the micelles of Tween80 was bioavailable and biodegradable. The research demonstrated the potential of surfactant-enhanced bioremediation of soils contaminated by hydrophobic organic compounds( HOCs).

  3. Effect of curcumin on the binding of cationic, anionic and nonionic surfactants with myoglobin

    Science.gov (United States)

    Mondal, Satyajit; Ghosh, Soumen

    2017-04-01

    Interaction of a globular protein, myoglobin and different surfactants has been studied in the absence and presence of curcumin in phosphate buffer at pH = 7.4 by UV-VIS spectrophotometry, fluorimetry and fluorescence polarization anisotropy methods. Results show that heme environment of myoglobin is changed by cationic cetyltrimethylammonium bromide (CTAB) and sodium N-dodecanoyl sarcosinate (SDDS). In the presence of curcumin, CTAB cannot change the heme; but SDDS can make change. Nonionic surfactant N-decanoyl-N-methylglucamine (Mega 10) cannot change the heme environment. Protein is unfolded by the surfactant. Curcumin can prevent the unfolding of protein in the low concentration region of ionic surfactants such as CTAB and SDDS. In nonionic surfactant media, curcumin accelerates the denaturation process. Due to myoglobin-curcumin complex formation, rotational motion of curcumin decreases in surfactant media and so anisotropy increases.

  4. Solid crystal network of self-assembled cyclodextrin and nonionic surfactant pseudorotaxanes.

    Science.gov (United States)

    Guerrero-Martínez, Andrés; Avila, David; Martínez-Casado, Francisco J; Ripmeester, John A; Enright, Gary D; De Cola, Luisa; Tardajos, Gloria

    2010-09-09

    The title system allows the straightforward formation of three-dimensional crystals of self-assembled pseudorotaxanes formed by the nonionic surfactant Igepal CO-520 and beta-cyclodextrin (beta-CD) in aqueous solution. The work involves a combination of X-ray powder diffraction, high resolution electron transmission microscopy, and (13)C CP/MAS NMR studies of the solid crystal, supported by single crystal structural analysis. The results indicate a lamellar self-assembly of pseudorotaxanes with preferential orientation and disorder in the structure. For the single crystal, the unit cell was found to be triclinic (P1) and contains a beta-CD dimer. The surfactant molecules are located in the channel formed by these dimers along the c axis of the crystal network. The individual pseudorotaxane structure is formed by a dimer of beta-CDs threaded by the oxyethylene hydrophilic segment of Igepal CO-520, and a beta-CD dimer that binds the hydrophobic region of the surfactant. Thus, as in a CD polyrotaxane structure, this system results in an ordered self-assembly of pseudorotaxanes through the formation of a network of hydrogen bonds between head-to-head beta-CD dimers. Moreover, the analysis of the (1)H NMR spectra in solutions of pseudorotaxanes formed by beta-CD and Igepals with different lengths of the hydrophilic tails indicates equal stoichiometry patterns of both oxyethyelene and hydrophobic regions for the different supramolecules. Whereas the common hydrophobic moiety threads two macrocycles, the ratio between complexed oxyehtlyene segments and beta-CD is 2.5 for the hydrophilic tails. All these results show that nonionic surfactants can be used as alternative and effective linear threads to polymers and copolymers in the synthesis of supramolecular polyrotaxane solid crystals with CDs.

  5. EVALUATION OF THE USEFULNESS OF CONTINUOUS FLOW ANALYSIS FOR THE STUDY OF ANIONIC SURFACTANTS AND NONIONIC SURFACTANTS IN WATER AND SEWAGE SAMPLES

    OpenAIRE

    2014-01-01

    In this paper, continuous flow analyzer has been examined for the usefulness for the determination of anionic surfactants and nonionics in real water and sewage samples. The study used a segmented flow analyzer (SFA) SAN++ (Skalar, Netherlands) with photometric detection. Environmental water and sewage samples of different origin and standard solutions were under test. By appropriate selection of analytical conditions in continuous flow system, it has been possible to obtain satisfactory valu...

  6. Conductometric study of sodium dodecyl sulfate - nonionic surfactant (Triton X-100, Tween 20, Tween 60, Tween 80 or Tween 85 mixed micelles in aqueous solution

    Directory of Open Access Journals (Sweden)

    Ćirin Dejan M.

    2012-01-01

    Full Text Available The present study is concerned with the determination of the critical micelle concentration (cmc of mixed micelles of sodium dodecyl sulfate with one of five nonionic surfactants (Triton X-100, Tween 20, Tween 60, Tween 80 or Tween 85 from conductance measurements. Based on the calculated values of the β parameters we have noticed that SDS-nonionic surfactants mostly showed strong synergistic effect. It was found that nonionic surfactants with mainly longer and more hydrophobic tail show stronger interactions with hydrophobic part of SDS, thus expressing stronger synergism. In SDS-Tween 80 binary system the strongest synergistic effect was noticed. SDS-Tween 85 micellar system showed antagonistic effect, most probably because the presence of the double bond in its three hydrophobic tails (three C18 tails makes it sterically rigid.

  7. Removal of anionic and nonionic surfactants in a wastewater treatment plant with anaerobic digestion: a comparative study

    OpenAIRE

    Prats Rico, Daniel; Ruiz Beviá, Francisco; Vázquez, Beatriz; Rodríguez Pastor, Manuel

    1995-01-01

    This paper presents a comparative study of the elimination of anionic surfactants (linear alkylbenzene sulphonates, LAS) and nonionic surfactants in a conventional municipal activated sludge plant. The LAS were analysed by high performance liquid chromatography, after extraction and purification. The nonionic surfactants was analysed by the Wickbold method. The elimination of the surl4actants in water, suspended solids and sludges were determined in the different stages of the ...

  8. The effect of electrolytes on emulsions stabilized by non-ionic surfactants

    NARCIS (Netherlands)

    Boomgaard, van den A.

    1985-01-01

    The objective of this study was to investigate the effect of high electrolyte concentrations on the stability of oil-in-water- emulsions stabilized by nonionic surfactants.In chapter 1 several stability mechanisms are briefly outlined and the distinction between coalescence and flocculation of an em

  9. Effects of non-ionic surfactants on the interactions between cellulases and tannic acid

    DEFF Research Database (Denmark)

    Olsen, Søren Nymand; Bohlin, Christina Helena; Murphy, Leigh

    2011-01-01

    Addition of non-ionic surfactants (NIS) is known to accelerate enzymatic lignocellulose hydrolysis. The mechanism behind this accelerating effect is still not elucidated but has been hypothesized to originate from favorable NIS–lignin interactions which alleviate non-productive adsorption...

  10. Non-ionic surfactants do not consistently improve the enzymatic hydrolysis of pure cellulose.

    Science.gov (United States)

    Zhou, Yan; Chen, Hongmei; Qi, Feng; Zhao, Xuebing; Liu, Dehua

    2015-04-01

    Non-ionic surfactants have been frequently reported to improve the enzymatic hydrolysis of pretreated lignocellulosic biomass and pure cellulose. However, how the hydrolysis condition, substrate structure and cellulase formulation affect the beneficial action of surfactants has not been well elucidated. In this work, it was found that the enzymatic hydrolysis of pure cellulose was not consistently improved by surfactants. Contrarily, high surfactant concentration, e.g. 5 g/L, which greatly improved the hydrolysis of dilute acid pretreated substrates, actually showed notable inhibition to pure cellulose conversion in the late phase of hydrolysis. Under an optimal hydrolysis condition, the improvement by surfactant was limited, but under harsh conditions surfactant indeed could enhance cellulose conversion. It was proposed that non-ionic surfactants could interact with substrates and cellulases to impact the adsorption behaviors of cellulases. Therefore, the beneficial action of surfactants on pure cellulose hydrolysis is influenced by hydrolysis condition, cellulose structural features and cellulase formulation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Cloud point phenomena for POE-type nonionic surfactants in a model room temperature ionic liquid.

    Science.gov (United States)

    Inoue, Tohru; Misono, Takeshi

    2008-10-15

    The cloud point phenomenon has been investigated for the solutions of polyoxyethylene (POE)-type nonionic surfactants (C(12)E(5), C(12)E(6), C(12)E(7), C(10)E(6), and C(14)E(6)) in 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF(4)), a typical room temperature ionic liquid (RTIL). The cloud point, T(c), increases with the elongation of the POE chain, while decreases with the increase in the hydrocarbon chain length. This demonstrates that the solvophilicity/solvophobicity of the surfactants in RTIL comes from POE chain/hydrocarbon chain. When compared with an aqueous system, the chain length dependence of T(c) is larger for the RTIL system regarding both POE and hydrocarbon chains; in particular, hydrocarbon chain length affects T(c) much more strongly in the RTIL system than in equivalent aqueous systems. In a similar fashion to the much-studied aqueous systems, the micellar growth is also observed in this RTIL solvent as the temperature approaches T(c). The cloud point curves have been analyzed using a Flory-Huggins-type model based on phase separation in polymer solutions.

  12. Partitioning of non-ionic surfactants between water and non-aqueous phase liquids (NAPLs) of chlorinated organics

    Science.gov (United States)

    KANG, S.; Jeong, H. Y.

    2013-12-01

    Due to the hydrophobic nature, chlorinated organic compounds penetrate soil and groundwater to form non-aqueous phase liquids (NAPLs). At the sites contaminated with such NAPLs, thus, surfactants are applied to increase the aqueous solubility of chlorinated organics via micellar solubilization. However, a portion of surfactants can be partitioned into NAPL phases by forming reverse micelles within them. Consequently, lesser amounts of surfactants are available for the micellar solubilization of chlorinated organics in the aqueous phase. In this study, we investigated the partitioning behavior of non-ionic surfactants (Tween 20, Tween 40, Tween 80, and Triton X-100) between water and a NAPL phase consisting of tetrachloroethylene (PCE), trichloroethylene (TCE), or chloroform (CF). According to the experimental results, the partitioning of surfactants in the water-NAPL systems was found to follow linear or Langmuir-type isotherms. Regardless of type of surfactants, the partitioning loss of surfactants into NAPLs became greater with the more hydrophilic (i.e., the lower water-NAPL interfacial tension) chlorinated organics: PCE Tween 80 << Triton X-100, suggesting that the greater partitioning occurred with the more hydrophobic (i.e., the lower hydrophilic-lipophilic balance, HLB) surfactant. Consistent with this postulation, the surfactant partitioning into PCE-NAPLs showed the similar trend. In case of TCE-NAPLs, however, the more hydrophobic Tween 40 was partitioned to a less extent than Tween 20. Therefore, the specific interaction of a NAPL-surfactant pair as well as their individual properties should be considered when selecting an effective surfactant for the remediation of a NAPL-contaminated site.

  13. Screening Nonionic Surfactants for Enhanced Biodegradation of Polycyclic Aromatic Hydrocarbons Remaining in Soil After Conventional Biological Treatment.

    Science.gov (United States)

    Adrion, Alden C; Nakamura, Jun; Shea, Damian; Aitken, Michael D

    2016-04-05

    A total of five nonionic surfactants (Brij 30, Span 20, Ecosurf EH-3, polyoxyethylene sorbitol hexaoleate, and R-95 rhamnolipid) were evaluated for their ability to enhance PAH desorption and biodegradation in contaminated soil after treatment in an aerobic bioreactor. Surfactant doses corresponded to aqueous-phase concentrations below the critical micelle concentration in the soil-slurry system. The effect of surfactant amendment on soil (geno)toxicity was also evaluated for Brij 30, Span 20, and POESH using the DT40 B-lymphocyte cell line and two of its DNA-repair-deficient mutants. Compared to the results from no-surfactant controls, incubation of the bioreactor-treated soil with all surfactants increased PAH desorption, and all except R-95 substantially increased PAH biodegradation. POESH had the greatest effect, removing 50% of total measured PAHs. Brij 30, Span 20, and POESH were particularly effective at enhancing biodegradation of four- and five-ring PAHs, including five of the seven carcinogenic PAHs, with removals up to 80%. Surfactant amendment also significantly enhanced the removal of alkyl-PAHs. Most treatments significantly increased soil toxicity. Only the no-surfactant control and Brij 30 at the optimum dose significantly decreased soil genotoxicity, as evaluated with either mutant cell line. Overall, these findings have implications for the feasibility of bioremediation to achieve cleanup levels for PAHs in soil.

  14. Synthesis and properties evaluation of nonionic-anionic surfactants suitable for enhanced oil recovery using sea water

    Energy Technology Data Exchange (ETDEWEB)

    Sha Ou [Lanzhou Inst. of Chemical Physics, Chinese Academy of Sciences (China); Shanghai Petrochemical Research Inst., SINOPEC (China); Zhang Weidong [Shanghai Petrochemical Research Inst., SINOPEC (China); Lu Runhua [Chengdu Inst. of Biology, Chinese Academy of Sciences (China)

    2008-03-15

    In view of imperfections of conventional anionic and nonionic surfactants used for enhanced oil recovery, especially the characteristics of high salinity and high Calcium/Magnesium for sea water flooding, a new novel displacement agent suitable for sea water flooding was synthesized through alkoxylation, epoxidation, sulfonation reaction with fatty alcohol as core. The structure of the product was characterized by IR. The properties of the product, including salt tolerance, temperature resistance etc. were evaluated. At 70 C, when the concentration of this surfactant is 0.3%, the interfacial tension between simulated water solution and Bohai1A-4 well crude reaches 10{sup -3} mN/m order, the salt tolerance reaches 50 000 mg/L, the resistance to calcium and magnesium reaches 2000 mg/L. The laboratory physical simulation test shows that the binary complex system (polymer + surfactant) can enhance the recovery ratio by 17.9%, while better synergistic effect of the system is obtained. (orig.)

  15. Fluorophotometric determination of critical micelle concentration (CMC) of ionic and non-ionic surfactants with carbon dots via Stokes shift.

    Science.gov (United States)

    Lavkush Bhaisare, Mukesh; Pandey, Sunil; Shahnawaz Khan, M; Talib, Abou; Wu, Hui-Fen

    2015-01-01

    A new and facile method for the determination of critical micelle concentration (CMC) of ionic and non-ionic surfactants is proposed in this article. Carbon dots exhibited substantial fluorescence and therefore enhanced the sensitivity of this evaluation. Understanding the formation of surfactant micelles is vital for the applications of biomedicine such as drug fabrication and smart molecular vehicles in delivering therapeutic dosage to various molecular sites. The fluorescence property of carbon dots was utilized for the first time to estimate the critical micelle concentration of surfactants. The central concept of the approach is based on the Stokes shift determination of a system composed of constant amount of carbon dots with varying concentrations of ionic and non-ionic surfactants. The synthesized carbon dots were characterized by FTIR, TEM, XRD, Raman, UV, and fluorescence spectroscope. The carbon dots were excited at 280 nm so as to obtain maximum emission for the Stokes shift measurement. The CMC value of cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl sulfate (SDS), Triton X-100, dodecyldimethyl(3-sulfopropyl)ammonium hydroxide (SB-12) evaluated by this approach was found to be 0.98, 7.3, 0.19, and 3.5mM, respectively. The signals of spectra were assigned and explained in terms of both electron transitions between specific molecular orbital and the interaction with solvent.

  16. Effect of anionic and nonionic surfactants on the kinetics of the aerobic heterotrophic biodegradation of organic matter in industrial wastewater.

    Science.gov (United States)

    Liwarska-Bizukojc, Ewa; Scheumann, René; Drews, Anja; Bracklow, Ute; Kraume, Matthias

    2008-02-01

    While using the contemporary mathematical models for activated sludge systems, it is necessary to describe quantitatively the kinetics of microbiological processes and to characterise substrate (wastewater components in the influent) as well as biomass (activated sludge). In this paper, the kinetic parameters of the aerobic biodegradation of organic matter in wastewater containing synthetic surfactants in an activated sludge system were determined and discussed. Also, the composition of the tested wastewater was estimated and expressed as COD fractions. Five synthetic surfactants, three anionic and two nonionic, of different chemical structure were investigated. Each of them was tested separately and dissolved in wastewater to obtain a concentration of 50 mgl(-1), which can be found in some industrial wastewater. The presence of the elevated amount of synthetic surfactants in wastewater decreased the affinity of biomass to substrate. Nevertheless, maximum specific growth rates (micromax) of heterotrophic biomass exposed to wastewater containing surfactants were high but usually lower than micromax estimated for wastewater without surfactant. Surfactants, which contain a benzene ring, were the most likely to deteriorate wastewater treatment processes in the activated sludge systems.

  17. The polydispersity effect of distributed oxyethylene chains on the cloud points of nonionic surfactants.

    Science.gov (United States)

    Kim, Hui Chan; Kim, Jong-Duk

    2010-12-15

    The cloud points of aqueous solutions containing polyoxyethylene surfactant molecules with a distribution of chain lengths were studied for several nonionic surfactants. Experimentally, the cloud points increased as the oxyethylene chain lengths increased with a linear or logarithmic relation of the number of oxyethylates, as proposed by Schott. An experimental scale, the p-Po scale, was previously developed to correspond to the cloud points, where p is the average number of oxyethylene units per molecule and Po is the shortest chain length reference. However, no previous prediction methods of cloud point addressed systems containing a range of chain lengths. In this work, we propose a rescaling of the representative chain length as s-Po, where s is the cloud point-weighted mean ethylene oxide chain below p, and approximated as (p-Po)/PDI where PDI is the polydispersity index. Using the rescaled length, the experimental data for C(12)Es (lauryl alcohol ethoxylate, LAE), NPE-10 (nonyl phenol ethoxylate) and TDE-10 (tridecyl alcohol ethoxylate) were successfully predicted with no additional parameters, such as {(p-Po)/(PDI)}/CP=a+b{(p-Po)/(PDI)}, where PDI indicates the Broadness of the chain length distribution.

  18. Choice of nonionic surfactant used to formulate type IIIA self-emulsifying drug delivery systems and the physicochemical properties of the drug have a pronounced influence on the degree of drug supersaturation that develops during in vitro digestion.

    Science.gov (United States)

    Devraj, Ravi; Williams, Hywel D; Warren, Dallas B; Porter, Christopher J H; Pouton, Colin W

    2014-04-01

    The performance of self-emulsifying drug delivery systems (SEDDS) is influenced by their tendency to generate supersaturated systems during dispersion and digestion in the gastrointestinal tract. This study investigated the effect of drug loading on supersaturation during digestion of fenofibrate or danazol SEDDS, each formulated using long-chain lipids and a range of nonionic surfactants. Supersaturation was described by the maximum supersaturation ratio (SR(M) ) produced by in vitro digestion. This parameter was calculated as the ratio of the total concentration of drug present in the digestion vessel versus the drug solubility in the colloidal phases formed by digestion of the SEDDS. SR(M) proved to be a remarkable indicator of performance across a range of lipid-based formulations. SEDDS containing danazol showed little evidence of precipitation on digestion, even at drug loads approaching saturation in the formulation. In contrast, fenofibrate crystallized extensively on digestion of the corresponding series of SEDDS, depending on the drug loading. The difference was explained by the generation of higher SR(M) values by fenofibrate formulations. A threshold SR(M) of 2.5-2.6 was identified in six of the seven SEDDS. This is not a definitive threshold for precipitation, but in general when SR(M) is greater than 3, fenofibrate supersaturation could not be maintained. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  19. Formation and stability of nanoemulsions with mixed ionic-nonionic surfactants.

    Science.gov (United States)

    Wang, Lijuan; Tabor, Rico; Eastoe, Julian; Li, Xuefeng; Heenan, Richard K; Dong, Jinfeng

    2009-11-14

    A simple, low-energy two-step dilution process has been applied with binary mixtures of ionic-nonionic surfactants to prepare nanoemulsions. The systems consist of water/DDAB-C(12)E(5)/decane. Nanoemulsions were obtained by dilution of concentrates located in bicontinuous microemulsion or lamellar liquid crystal phase regions. The nanoemulsions generated were investigated both by contrast-variation small-angle neutron scattering (SANS) and dynamic light scattering (DLS). The SANS profiles show that C(12)E(5) nanodroplets suffer essentially no structural change on incorporation of the cationic DDAB surfactant, except for increased electrostatic repulsive interactions. Interestingly, SANS indicated that the preferred droplet sizes were hardly affected by the surfactant mixture composition (up to a DDAB molar ratio (m(DDAB)/(m(DDAB) + m(C(12)E(5))) of 0.40) and droplet volume fraction, phi, between 0.006 and 0.120. No notable changes in the structure or radius of nanoemulsion droplets were observed by SANS over the test period of 1 d, although the droplet number intensity decreased significantly in systems stabilized by C(12)E(5) only. However, the DLS sizing shows a marked increase with time, with higher droplet volume fractions giving rise to the largest changes. The discrepancy between apparent nanoemulsion droplet size determined by DLS and SANS data can be attributed to long-range droplet interactions occurring outside of the SANS sensitivity range. The combined SANS and DLS results suggest flocculation is the main mechanism of instability for these nanoemulsions. The flocculation rate is shown to be significantly retarded by addition of the charged DDAB, which may be due to enhanced electrostatic repulsive forces between droplets, leading to improved stability of the nanoemulsions.

  20. Solubilization and degradation of perchloroethylene (PCE) in cationic and nonionic surfactant solutions

    Institute of Scientific and Technical Information of China (English)

    Sivaram Harendra; Cumaraswamy Vipulanandan

    2011-01-01

    Solubilization of perchloroethylene (PCE) in a nonionic (Triton X-100) and a cationic (cetyltrimethylammonium bromide (CTAB)) surfactant solutions and the degradation of surfactant solubilized PCE using fine to nanosize Fe and bi-metallic Fe-Ni particles were investigated.Micelle partition coefficients (Km) and molar solubility ratio (MSR) for PCE in 10 g/L of surfactant solutions have been quantified and the solubility of PCE (100 mg/L in water) in the surfactant solutions increased by about ten fold.Of the two surfactants studied,Triton X-100 solubilized the higher amount of PCE per gram of surfactant.To degrade solubilized PCE,both iron and bimetallic Fe-Ni particles were used in continuously stirred batch reactors.The iron and bi-metallic particles were synthesized using the solution method and the particles were characterized using the SEM,EDS,TEM and XRD.The PCE solubilized up to 500 mg/L in both surfactant solutions were totally degraded at various rates by 200 g/L of bi-metallic Fe-Ni particles in less than 20 hr,which is the highest concentration of PCE degraded in the shortest time compared to data in the literature.The degradations of PCE solubilized in surfactant solutions were represented by nonlinear kinetic relationships which depended on the type of surfactant used for solubilizing the PCE.

  1. New theoretical framework for designing nonionic surfactant mixtures that exhibit a desired adsorption kinetics behavior.

    Science.gov (United States)

    Moorkanikkara, Srinivas Nageswaran; Blankschtein, Daniel

    2010-12-21

    How does one design a surfactant mixture using a set of available surfactants such that it exhibits a desired adsorption kinetics behavior? The traditional approach used to address this design problem involves conducting trial-and-error experiments with specific surfactant mixtures. This approach is typically time-consuming and resource-intensive and becomes increasingly challenging when the number of surfactants that can be mixed increases. In this article, we propose a new theoretical framework to identify a surfactant mixture that most closely meets a desired adsorption kinetics behavior. Specifically, the new theoretical framework involves (a) formulating the surfactant mixture design problem as an optimization problem using an adsorption kinetics model and (b) solving the optimization problem using a commercial optimization package. The proposed framework aims to identify the surfactant mixture that most closely satisfies the desired adsorption kinetics behavior subject to the predictive capabilities of the chosen adsorption kinetics model. Experiments can then be conducted at the identified surfactant mixture condition to validate the predictions. We demonstrate the reliability and effectiveness of the proposed theoretical framework through a realistic case study by identifying a nonionic surfactant mixture consisting of up to four alkyl poly(ethylene oxide) surfactants (C(10)E(4), C(12)E(5), C(12)E(6), and C(10)E(8)) such that it most closely exhibits a desired dynamic surface tension (DST) profile. Specifically, we use the Mulqueen-Stebe-Blankschtein (MSB) adsorption kinetics model (Mulqueen, M.; Stebe, K. J.; Blankschtein, D. Langmuir 2001, 17, 5196-5207) to formulate the optimization problem as well as the SNOPT commercial optimization solver to identify a surfactant mixture consisting of these four surfactants that most closely exhibits the desired DST profile. Finally, we compare the experimental DST profile measured at the surfactant mixture condition

  2. Modeling of the Critical Micelle Concentration (CMC) of Nonionic Surfactants with an Extended Group-Contribution Method

    DEFF Research Database (Denmark)

    Mattei, Michele; Kontogeorgis, Georgios; Gani, Rafiqul

    2013-01-01

    A group-contribution (GC) property prediction model for estimating the critical micelle concentration (CMC) of nonionic surfactants in water at 25 °C is presented. The model is based on the Marrero and Gani GC method. A systematic analysis of the model performance against experimental data......; and carbohydrate derivate ethers, esters, and thiols. The model developed consists of linear group contributions, and the critical micelle concentration is estimated using the molecular structure of the nonionic surfactant alone. Compared to other models used for the prediction of the critical micelle...... is carried out using data for a wide range of nonionic surfactants covering a wide range of molecular structures. As a result of this procedure, new third order groups based on the characteristic structures of nonionic surfactants are defined and are included in the Marrero and Gani GC model. In this way...

  3. Application of hydrophilic-lypophilic balance (HLB) number to optimize a compatible non-ionic surfactant for dried aerial conidia of Beauveria bassiana

    Science.gov (United States)

    The hydrophilic-lipophilic balance (HLB) number system was used to optimize a compatible non-ionic surfactant, TDA(polyoxyethylene tridecyl ether) in formulations for two Beauveria bassiana strains, NI8 and GHA. The optimal HLB number for TDA was determined on the basis of wetting times for conidia...

  4. On the characterization of host-guest complexes : Surface tension, calorimetry, and molecular dynamics of cyclodextrins with a non-ionic surfactant

    NARCIS (Netherlands)

    Pineiro, Angel; Banquy, Xavier; Perez-Casas, Silvia; Tovar, Edgar; Garcia, Abel; Villa, Alessandra; Amigo, Alfredo; Mark, Alan E.; Costas, Miguel

    2007-01-01

    Three host-guest systems have been characterized using surface tension (sigma), calorimetry, and molecular dynamics simulations (MD). The hosts were three native cyclodextrins (CD) and the guest the non-ionic carbohydrate surfactant octyl-beta-d-glucopyranoside. It is shown that, for any host-guest

  5. On the characterization of host-guest complexes : Surface tension, calorimetry, and molecular dynamics of cyclodextrins with a non-ionic surfactant

    NARCIS (Netherlands)

    Pineiro, Angel; Banquy, Xavier; Perez-Casas, Silvia; Tovar, Edgar; Garcia, Abel; Villa, Alessandra; Amigo, Alfredo; Mark, Alan E.; Costas, Miguel

    2007-01-01

    Three host-guest systems have been characterized using surface tension (sigma), calorimetry, and molecular dynamics simulations (MD). The hosts were three native cyclodextrins (CD) and the guest the non-ionic carbohydrate surfactant octyl-beta-d-glucopyranoside. It is shown that, for any host-guest

  6. Investigation of extractive microbial transformation in nonionic surfactant micelle aqueous solution using response surface methodology.

    Science.gov (United States)

    Xue, Yingying; Qian, Chen; Wang, Zhilong; Xu, Jian-He; Yang, Rude; Qi, Hanshi

    2010-01-01

    Extractive microbial transformation of L-phenylacetylcarbinol (L-PAC) in nonionic surfactant Triton X-100 micelle aqueous solution was investigated by response surface methodology. Based on the Box-Behnken design, a mathematical model was developed for the predication of mutual interactions between benzaldehyde, Triton X-100, and glucose on L-PAC production. It indicated that the negative or positive effect of nonionic surfactant strongly depended on the substrate concentration. The model predicted that the optimal concentration of benzaldehyde, Triton X-100, and glucose was 1.2 ml, 15 g, and 2.76 g per 100 ml, respectively. Under the optimal condition, the maximum L-PAC production was 27.6 mM, which was verified by a time course of extractive microbial transformation. A discrete fed-batch process for verification of cell activity was also presented.

  7. Binary coalescence of gas bubbles in the presence of a non-ionic surfactant.

    Science.gov (United States)

    Duerr-Auster, N; Gunde, R; Mäder, R; Windhab, Erich J

    2009-05-15

    The coalescence behavior of air bubbles in a dilute aqueous surfactant solution of a polyglycerol fatty acid ester (PGE), a commercial non-ionic surfactant, is investigated in a binary coalescence experiment. The focus is on the influence of the ionic strength of the solution on the rate of coalescence. Results are compared with the adsorption kinetics and surface shear/dilatational rheological properties of the surfactant. Experiments show that the coalescence frequency is significantly lower at low ionic strength, and that bubble stability increases with increasing aging time. Stabilization occurs via surfactant adsorption and a resulting electrostatic and/or steric repulsive force. The electrostatic force presumably originates from small amounts of anionic fatty acid soaps, which are residues from the industrial synthesis. The steric force can be related to the adsorption of visco-elastic layers of PGE at the air-water interface.

  8. Small angle neutron scattering study of two nonionic surfactants in water micellar solutions

    Indian Academy of Sciences (India)

    Rajewska Aldona

    2008-11-01

    Two classic nonionic surfactants – C14E7 (heptaethylene glycol monotetra-decyl ether) and C10E7 (heptaethylene glycol monodecyl ether) were investigated in heavy water solution for concentration = 0.17% (dilute regime) at different temperatures in the range = 10–35°C by small angle neutron scattering (SANS) method. In the case of C14E7 surfactant – for all temperatures at = 0.17% there are two axial ellipsoidal micelles with longer axis 15 nm at 10°C and 49.5 nm at 35°C in investigated solutions. For C10E7 surfactant at the same concentration of solution and temperature – two axial ellipsoidal micelles were observed, too. The longer axis is equal to 7.5 nm at 10°C, 9 nm at 20°C and at 35°C this axis is equal to 12 nm. Micelles of C10E7 nonionic surfactant are smaller than those of C14E7 surfactant in the same experimental conditions.

  9. Mobilization of arsenic from contaminated sediment by anionic and nonionic surfactants.

    Science.gov (United States)

    Liang, Chuan; Peng, Xianjia

    2017-06-01

    The increasing manufacture of surfactants and their wide application in industry, agriculture and household detergents have resulted in large amounts of surfactant residuals being discharged into water and distributed into sediment. Surfactants have the potential to enhance arsenic mobility, leading to risks to the environment and even human beings. In this study, batch and column experiments were conducted to investigate arsenic mobilization from contaminated sediment by the commercial anionic surfactants sodium dodecylbenzenesulfonate (SDBS), sodium dodecyl sulfate (SDS), sodium laureth sulfate (AES) and nonionic surfactants phenyl-polyethylene glycol (Triton X-100) and polyethylene glycol sorbitan monooleate (Tween-80). The ability of surfactants to mobilize arsenic followed the order AES>SDBS>SDS≈Triton X-100>Tween 80. Arsenic mobilization by AES and Triton X-100 increased greatly with the increase of surfactant concentration and pH, while arsenic release by SDBS, SDS and Tween-80 slightly increased. The divalent ion Ca(2+) caused greater reduction of arsenic mobilization than Na(+). Sequential extraction experiments showed that the main fraction of arsenic mobilized was the specifically adsorbed fraction. Solid phase extraction showed that arsenate (As(V)) was the main species mobilized by surfactants, accounting for 65.05%-77.68% of the total mobilized arsenic. The mobilization of arsenic was positively correlated with the mobilization of iron species. The main fraction of mobilized arsenic was the dissolved fraction, accounting for 70% of total mobilized arsenic. Copyright © 2016. Published by Elsevier B.V.

  10. Effect of Temperature on the Critical Micelle Concentration and Micellization Thermodynamic of Nonionic Surfactants: Polyoxyethylene Sorbitan Fatty Acid Esters

    Directory of Open Access Journals (Sweden)

    Ehsan Mohajeri

    2012-01-01

    Full Text Available In this study, non-ionic surfactants, polyoxyethylene sorbitan fatty acid esters (polysorbate are chosen to examine the temperature effect on the CMC over a wide temperature range. The enthalpy and entropy of micelle formation are evaluated according to the phase separation model. The surface tension of solutions was determined by means of Du Nöuys ring. The CMC values were taken from the sharp breaks in the surface tension vs. logarithms of surfactant concentration plots. As the surfactants' chain length increases the CMC at a constant temperature decreases, which is directly related to the decrease of hydrophilicity of the molecules. For each surfactant, as the system temperature increases, the CMC initially decreases and then increases, owing to the smaller probability of hydrogen bond formation at higher temperatures. The onset of micellization tends to occur at higher concentrations as the temperature increases. To evaluate the enthalpy of micellization, the CMCs are first correlated by a polynomial equation. It is found that ∆Gºm decreases monotonically as the temperature increases over the whole temperature range. Both ∆Hºm and ∆Sºm appear to be decrease monotonically with an increase in temperature. The compensation temperature was found to be 42 ºC by linear regression over the whole temperature range and for all three surfactant systems together.

  11. Effect of nonionic surfactant on wetting behavior of an evaporating drop under a reduced pressure environment.

    Science.gov (United States)

    Sefiane, Khellil

    2004-04-15

    The evaporation of sessile drops at reduced pressure is investigated. The evaporation of water droplets on aluminum and PTFE surfaces at reduced pressure was compared. It was found that water droplets on an aluminum surface exhibit a 'depinning jump' at subatmospheric pressures. This is when a pinned droplet suddenly depins, with an increase in contact angle and a simultaneous decrease in the base width. The evaporation of sessile water droplets with a nonionic surfactant (Triton X-100) added to an aluminum surface was then studied. The initial contact angle exhibited a minimum at 0.001 wt% Triton X-100. A maximum in the evaporation rate was also observed at the same concentration. Droplets with low surfactant concentrations are found to exhibit the 'depinning jump.' It is thought that the local concentration of the surfactant causes a gradient of surface tension. The balance at the contact angle is dictated by complex phenomena, including surfactant diffusion and adsorption processes at interfaces. Due to the strong evaporation near the triple line, an accumulation of the surfactant will lead to a surface tension gradient along the interface. The gradient of surface tension will influence the wetting behavior (Marangoni effect). At low surfactant concentrations the contact line depins under the strong effect of surface tension gradient that develops spontaneously over the droplet interface due to surfactant accumulation near the triple line. The maximum evaporation rate corresponds to a minimum contact angle for a pinned droplet.

  12. Nonionic surfactant enhanced semipermanent coatings for capillary electrophoresis of inorganic anions without use of organic additives.

    Science.gov (United States)

    Yao, Lihua; Liu, Qian; Li, Yi; Yao, Shouzhuo

    2011-09-01

    Separation of inorganic anions by capillary electrophoresis (CE) is usually conducted in co-electroosmotic mode due to the large electrophoretic mobilities of inorganic anions. Semipermanent surfactant coatings have been shown to be effective for CE of inorganic anions due to their strong capability of electroosmotic flow (EOF) manipulation. However, semipermanent coatings often suffer from their unsatisfactory stability. In addition, organic solvent additives are usually required to adjust the selectivity, which also aggravate the degradation of coating. In this work, a novel semipermanent coating consisting of cationic Gemini surfactant 18-10-18 and nonionic surfactant Tween 20 was developed to separate inorganic anions in CE. This coating is easy to prepare and more stable than pure Gemini coating. The introduction of nonionic surfactant in the coating not only suppresses the reversed EOF but can also adjust the selectivity of separation. Good separations of six model anions were achieved, the separation efficiency was as high as 65040-169700 plates/m and the RSDs of the migration times were less than 0.5 and 2.5% for run-to-run and day-to-day assays, respectively. Calibration curves were linear in the range of 0.05-5.0 mM; the detection limits ranged from 20 to 50 μM. More importantly, no organic solvents are required in the background buffer to achieve the satisfactory separations. This guarantees the coating stability and makes the method greener than most of other methods for CE of inorganic anions.

  13. Preparation and Evaluation of Monodisperse Nonionic Surfactants Based on Fluorine-Containing Dicarbamates.

    Science.gov (United States)

    Mureau; Trabelsi; Guittard; Geribaldi

    2000-09-15

    Novel bipodal surfactants of fluorine-containing carbamate type were synthesized with satisfactory yields from the action of fluorinated diisocyanates on oligooxyethylmonomethylated ethers without solvent. The synthetic pathways via malonic intermediates were elaborated in order to use low-price commercially available compounds such as 2-F-alkylethyl iodides and oligooxyethylmonomethylated ethers as starting materials. This new class of nonionic surfactants contains one hydrophobic part and one oleophobic part, and shows peculiar properties due to the presence of two hydrophilic parts (bipodal). All these compounds are monodisperse, i.e, include a perfectly defined number of oxyethylene units. Compared with their bipodal homologues previously described within the F-alkylated series, these new structures were easily obtained from commercial raw materials and are stable against pH media. The evaluation of their behavior at the air-water interface has been studied by measurements of surface tension versus concentration. This allows us to show clearly the variation of the critical micelle concentration (cmc) from 1.1x10(-5) to 9.8x10(-3) mol.l(-1), and of the surface area per surfactant molecule versus studied structures. The dicarbamates of oligooxyethylmonomethylether of 3-(F-alkyl)propyl so realized exhibit noteworthy properties as nonionic fluorinated surfactants. Copyright 2000 Academic Press.

  14. Accumulation of yellow Monascus pigments by extractive fermentation in nonionic surfactant micelle aqueous solution.

    Science.gov (United States)

    Xiong, Xu; Zhang, Xuehong; Wu, Zhenqiang; Wang, Zhilong

    2015-02-01

    Monascus species can produce various secondary metabolites of polyketide structure. In the current study, it is found that an interesting phenomenon, i.e., submerged culture of Monascus species in an aqueous solution majorly accumulated intracellular orange Monascus pigments exhibiting one peak at 470 nm with absorbance of 32 OD while extractive fermentation in a nonionic surfactant micelle aqueous solution produced extracellular and intracellular yellow Monascus pigments exhibiting one peak at 410 nm with absorbance 30 OD and 12 OD, respectively. The spectrum profiles of both intracellular and extracellular Monascus pigments were affected by surfactant loading, extractive fermentation time, and surfactant adding time. Meanwhile, the instability of orange Monascus pigments in the extracellular nonionic surfactant micelle aqueous solution was also confirmed experimentally. The mechanism behind this phenomenon is attributed to the export of intracellular yellow Monascus pigments into its broth by extractive fermentation. The transferring of intracellular yellow Monascus pigments into its broth blocks yellow Monascus pigments from further enzymatic conversion or eliminates the feedback inhibition of yellow Monascus pigments based on the biosynthetic pathway of Monascus pigments.

  15. FLOTATION DE-INKING OF 50% ONP/ 50% OMG RECOVERED PAPERS MIXTURES USING NONIONIC SURFACTANT, SOAP, AND SURFACTANT/SOAP BLENDS

    Directory of Open Access Journals (Sweden)

    Jeremy Allix

    2010-11-01

    Full Text Available A laboratory flotation column equipped with Venturi aerators and an adjustable froth removal system was used to study the effect of calcium soap and a mixture of calcium soap/alkyl phenol ethoxylate surfactant on ink and fibres transfer during flotation de-inking of a 50% old newprint (ONP / 50% old magazines (OMG recovered papers mixture. Mass transport phenomena determining the yield of the flotation process were interpreted using model equations describing particle removal in terms of flotation, entrainment, and drainage in the froth. A decrease in the ink and mineral fillers flotation rate constant, drainage through the froth, and in fibre entrainment was observed when increasing the surfactant concentration. These trends were consistent with the typical dispersing action of the studied nonionic surfactant. An opposite effect on ink and fillers was observed when using calcium soap alone, and the increase in the flotation rate constant and drainage through the froth were consistent with the collecting and defoaming action of the calcium soap. Moreover, fibre entrainment decreased when increasing the soap concentration. The study of the surfactant/soap mixture highlighted the absence of synergy between the calcium soap and the surfactant.

  16. Conductometric study of sodium dodecyl sulfate - nonionic surfactant (Triton X-100, Tween 20, Tween 60, Tween 80 or Tween 85) mixed micelles in aqueous solution

    OpenAIRE

    Ćirin Dejan M; Poša Mihalj M.; Krstonošić Veljko S.; Milanović Maja Lj.

    2012-01-01

    The present study is concerned with the determination of the critical micelle concentration (cmc) of mixed micelles of sodium dodecyl sulfate with one of five nonionic surfactants (Triton X-100, Tween 20, Tween 60, Tween 80 or Tween 85) from conductance measurements. Based on the calculated values of the β parameters we have noticed that SDS-nonionic surfactants mostly showed strong synergistic effect. It was found that nonionic surfactants with mainly longer and more hydrophobic tail s...

  17. Synthesis, surface properties and antimicrobial activity of some germanium nonionic surfactants.

    Science.gov (United States)

    Zaki, Mohamed F; Tawfik, Salah M

    2014-01-01

    Esterification reaction between different fatty acid namely; lauric, stearic, oleic and linoleic acids and polyethylene glycol-400 were performed. The produced polyethylene glycol ester were reacted with p-amine benzoic acid followed by condensation reaction with germanium dioxide in presence of sodium carbonate to form desired germinate surfactants. The chemical structures of the synthesized surfactants were determined using different spectra tools. The surface parameter including: the critical micelle concentration (CMC), effectiveness (π(cmc)), efficiency (Pc20), maximum surface excess (Γ(max)) and minimum surface area (A(min)), were calculated from the surface tension measurements. The synthesized surfactants showed higher surface activity. The thermodynamic parameters showed that adsorption and micellization processes are spontaneous. It is clear that the synthesized nonionic surfactants showed their tendency towards adsorption at the interfaces and also micellization in the bulk of their solutions. The synthesized surfactants were tested against different strain of bacteria using inhibition zone diameters. The synthesized surfactants showed good antimicrobial activities against the tested microorganisms including Gram positive, Gram negative as well as fungi. The promising inhibition efficiency of these compounds against the sulfate reducing bacteria facilitates them to be applicable as new categories of sulfate reducing bacteria biocides.

  18. Anomalous thickness variation of the foam films stabilized by weak non-ionic surfactants.

    Science.gov (United States)

    Qu, Xuan; Wang, Liguang; Karakashev, Stoyan I; Nguyen, Anh V

    2009-09-15

    The constant thickness (H) of metastable free films of various non-ionic surfactant solutions was measured at surfactant concentrations less than the critical micelle concentrations or solubility limits with fixed 5x10(-5) M sodium chloride (NaCl) serving as the background electrolyte. The surfactants include n-pentanol, n-octanol, methyl isobutyl carbinol (MIBC), polypropylene glycol (PPG-400), tetraethylene glycol monooctyl ether (C(8)E(4)), and tetraethylene glycol monodecyl ether (C(10)E(4)). H was interferometrically measured. For each surfactant in this study, the H-versus-surfactant-concentration curve finds a peak at a concentration around 5x10(-6)-1x10(-5) M and a valley at a higher concentration. The measured H values were compared to those predicted from the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, which considers solely the contribution from electrostatic double-layer repulsion with van der Waals attraction being neglected in the present work. In determining the double-layer repulsion, the ionic strength was determined from the electrolytic conductivity measurement of the film-forming solutions and the surface potential was estimated from the zeta-potential measurement of air bubbles. It was found that the DLVO theory failed to explain the thickness variance with surfactant concentration, implying that additional non-DLVO attractive forces might be required to explain the experimental results. Finally, the possible origins of these attractive forces were discussed.

  19. Surfactant Sector Needs Urgent Readjustment

    Institute of Scientific and Technical Information of China (English)

    Huang Hongzhou

    2007-01-01

    @@ Surfactant industrial system has been basically established After 50 years' development, China has already established a surfactant industrial system with a relatively complete product portfolio and can produce 4714 varieties of surfactants in cationic,anionic, nonionic and amphoteric categories.

  20. Self-assembly thermodynamics of pH-responsive amino-acid-based polymers with a nonionic surfactant.

    Science.gov (United States)

    Bogomolova, Anna; Keller, Sandro; Klingler, Johannes; Sedlak, Marian; Rak, Dmytro; Sturcova, Adriana; Hruby, Martin; Stepanek, Petr; Filippov, Sergey K

    2014-09-30

    The behavior of pH-responsive polymers poly(N-methacryloyl-l-valine) (P1), poly(N-methacryloyl-l-phenylalanine) (P2), and poly(N-methacryloylglycyne-l-leucine) (P3) has been studied in the presence of the nonionic surfactant Brij98. The pure polymers phase-separate in an acidic medium with critical pHtr values of 3.7, 5.5, and 3.4, respectively. The addition of the surfactant prevents phase separation and promotes reorganization of polymer molecules. The nature of the interaction between polymer and surfactant depends on the amino acid structure in the side chain of the polymer. This effect was investigated by dynamic light scattering, isothermal titration calorimetry, electrophoretic measurements, small-angle neutron scattering, and infrared spectroscopy. Thermodynamic analysis revealed an endothermic association reaction in P1/Brij98 mixture, whereas a strong exothermic effect was observed for P2/Brij98 and P3/Brij98. Application of regular solution theory for the analysis of experimental enthalpograms indicated dominant hydrophobic interactions between P1 and Brij98 and specific interactions for the P2/Brij98 system. Electrophoretic and dynamic light scattering measurements support the applicability of the theory to these cases. The specific interactions can be ascribed to hydrogen bonds formed between the carboxylic groups of the polymer and the oligo(ethylene oxide) head groups of the surfactant. Thus, differences in polymer-surfactant interactions between P1 and P2 polymers result in different structures of polymer-surfactant complexes. Specifically, small-angle neutron scattering revealed pearl-necklace complexes and "core-shell" structures for P1/Brij98 and P2/Brij98 systems, respectively. These results may help in the design of new pH-responsive site-specific micellar drug delivery systems or pH-responsive membrane-disrupting agents.

  1. Effect of nonionic surfactant Brij 35 on the fate and transport of oxytetracycline antibiotic in soil.

    Science.gov (United States)

    Elsayed, Eman M; Prasher, Shiv O; Patel, Ramanbhai M

    2013-02-15

    In many parts of the world, river water is used for irrigation. Treated, partially treated, and even untreated water from wastewater treatment plants is discharged directly into rivers, thereby degrading the quality of the water. Consequently, irrigation water may contain surfactants which may affect the fate and transport of chemicals such as pesticides and antibiotics in agricultural soils. A field lysimeter study was undertaken to investigate the effect of the nonionic surfactant, Brij 35, on the fate and transport of an antibiotic, Oxytetracycline, commonly used in cattle farms. Nine PVC lysimeters, 1.0 m long × 0.45 m diameter, were packed with a sandy soil to a bulk density of 1.35 Mg m(-3). Cattle manure, containing Oxytetracycline, was applied at the surface of the lysimeters at the recommended rate of 10 t/ha. Each of three aqueous Brij 35 solutions, 0, 0.5 and 5 g L(-1) (i.e., 'good,' 'poor' and 'very poor' quality irrigation water) were each applied to the lysimeters in triplicate. Over a 90 day period, soil and leachate samples were collected and analyzed. Batch experiment results showed that the presence of the nonionic surfactant Brij 35 significantly reduced the sorption coefficient of OTC from 23.55 mL g(-1) in the aqueous medium to 19.49, 12.49 and 14.53 in the presence of Brij 35 at concentrations of 0.25, 2.5 and 5 g L(-1), respectively. Lysimeter results indicted the significant downward movement of OTC at depths of 60 cm into soil profile and leachate in the presence of surfactant. Thus, the reuse of wastewater containing surfactants might enhance the mobility of contaminants and increase ground water pollution.

  2. Thermodynamics of Micellization of Nonionic Surfactant Tween-40 in Presence of Additive Chloramine-T Using Clouding Phenomenon

    Directory of Open Access Journals (Sweden)

    A. A. Patil

    2010-01-01

    Full Text Available The phenomenon of solubilization of nonionic surfactant Tween-40 has been studied through the influence of additive chloramine-T in aqueous medium by measuring the cloud points (CP of the pure surfactant and with chloramine-T. The CP of pure surfactant was found to be increased with increasing concentration of Tween-40. The CP of mixed system shows increasing trends with increased chloramine-T. This is mainly due to increased micelle concentrations. The influence of chloramine-T on the cloud point of Tween-40 is a clear indication that the phenomenon of clouding is associated with the different micelles coalescing. Considering cloud point as threshold temperature of the solubility, the thermodynamic parameters of clouding process (ΔG0cl, ΔH0cl and ΔS0cl have been evaluated using “Phase Separation Model”. The phase separation results from micelle-micelle interaction. It was found that the overall clouding process was exothermic and ΔH0cl > TΔS0cl indicating that the process of clouding was guided by both enthalpy and entropy. This work supports the conjecture that the clouding is critical phenomenon rather than the growth of micelles. Findings of the present work supports to made the probable evidence of electrolyte-surfactant interactions in aqueous medium.

  3. Effective Surfactants Blend Concentration Determination for O/W Emulsion Stabilization by Two Nonionic Surfactants by Simple Linear Regression.

    Science.gov (United States)

    Hassan, A K

    2015-01-01

    In this work, O/W emulsion sets were prepared by using different concentrations of two nonionic surfactants. The two surfactants, tween 80(HLB=15.0) and span 80(HLB=4.3) were used in a fixed proportions equal to 0.55:0.45 respectively. HLB value of the surfactants blends were fixed at 10.185. The surfactants blend concentration is starting from 3% up to 19%. For each O/W emulsion set the conductivity was measured at room temperature (25±2°), 40, 50, 60, 70 and 80°. Applying the simple linear regression least squares method statistical analysis to the temperature-conductivity obtained data determines the effective surfactants blend concentration required for preparing the most stable O/W emulsion. These results were confirmed by applying the physical stability centrifugation testing and the phase inversion temperature range measurements. The results indicated that, the relation which represents the most stable O/W emulsion has the strongest direct linear relationship between temperature and conductivity. This relationship is linear up to 80°. This work proves that, the most stable O/W emulsion is determined via the determination of the maximum R² value by applying of the simple linear regression least squares method to the temperature-conductivity obtained data up to 80°, in addition to, the true maximum slope is represented by the equation which has the maximum R² value. Because the conditions would be changed in a more complex formulation, the method of the determination of the effective surfactants blend concentration was verified by applying it for more complex formulations of 2% O/W miconazole nitrate cream and the results indicate its reproducibility.

  4. Tools to discover anionic and nonionic polyfluorinated alkyl surfactants by liquid chromatography electrospray ionisation mass spectrometry

    DEFF Research Database (Denmark)

    Trier, Xenia; Granby, Kit; Christensen, Jan H.

    2011-01-01

    A tiered approach is proposed for the discovery of unknown anionic and nonionic polyfluorinated alkyl surfactants (PFASs) by reversed phase ultra high performance liquid chromatography (UHPLC) – negative electrospray ionisation – quadrupole time of flight mass spectrometry (UHPLC......–ESI−–QTOF–MS). The chromatographic separation, ionisation and detection of PFASs mixtures, was achieved at high pH (pH=9.7) with NH4OH as additive. To distinguish PFASs from other chemicals we used the characteristic negative mass defects of PFASs, their specific losses of 20Da (HF) and the presence of series of chromatographic...

  5. Effects of ionic and nonionic surfactants on milk shell wettability during co-spray-drying of whole milk particles.

    Science.gov (United States)

    Lallbeeharry, P; Tian, Y; Fu, N; Wu, W D; Woo, M W; Selomulya, C; Chen, X D

    2014-09-01

    Mixing surfactants with whole milk feed before spray drying could be a commercially favorable approach to produce instant whole milk powders in a single step. Pure whole milk powders obtained directly from spray drying often have a high surface fat coverage (up to 98%), rendering them less stable during storage and less wettable upon reconstitution. Dairy industries often coat these powders with lecithin, a food-grade surfactant, in a secondary fluidized-bed drying stage to produce instant powders. This study investigated the changes in wetting behavior on the surface of a whole milk particle caused by the addition of surfactants before drying. Fresh whole milk was mixed with 0.1% (wt/wt) Tween 80 or 1% (wt/wt) lecithin (total solids), and the wetting behavior of the shell formed by each sample was captured using a single-droplet drying device at intermediate drying stages as the shell was forming. The addition of surfactants improved shell wettability from the beginning of shell formation, producing more wettable milk particles after drying. The increase in surfactant loading by 10 times reduced the wetting time from around 30s to 30s). We proposed that Tween 80 could adsorb at the oil-water interface of fat globules, making the surface fat more wettable, whereas lecithin tends to combine with milk proteins to form a complex, which then competes for the air-water surface with fat globules. Spray-drying experiments confirmed the greatly improved wettability of whole milk powders by the addition of either 0.1% (wt/wt) Tween 80 or 1% (wt/wt) lecithin; wetting time was reduced from 35±4s to drying system has been used to elucidate the complex interactions between ionic or nonionic surfactants and milk components (both proteins and fat), as well as the resultant effect on the development of milk particle functionality during drying.

  6. Separation of cationic analytes by nonionic micellar electrokinetic chromatography using polyoxyethylene lauryl ether surfactants with different polyoxyethylene length.

    Science.gov (United States)

    Quirino, Joselito P; Kato, Masaru

    2014-09-01

    Although nonionic micellar electrokinetic chromatography is used for the separation of charged compounds that are not easily separated by capillary zone electrophoresis, the effect of the hydrophilic moiety of the nonionic surfactant has not been studied well. In this study, the separation of ultraviolet-absorbing amino acids was studied in electrokinetic chromatography using neutral polyoxyethylene lauryl ether surfactants (Adekatol) in the separation solution. The effect of the polyethylene moiety (the number of repeating units was from 6.5 to 50) of the hydrophobic test amino acids (methionine, tryptophan, and tysorine) was studied using a 10 cm effective length capillary. The separation mechanism was based on hydrophobic as well as hydrogen bonding interactions at the micellar surface, which was made of the polyoxyethylene moiety. The length of the polyoxyethylene moiety of the surfactants was not important in nonionic micellar electrokinetic chromatography mode.

  7. Small-angle neutron scattering studies of nonionic surfactant: Effect of sugars

    Indian Academy of Sciences (India)

    K Shivaji Sharma; J V Joshi; V K Aswal; P S Goyal; A K Rakshit

    2004-08-01

    Micellar solution of nonionic surfactant -dodecyloligo ethyleneoxide surfactant, decaoxyethylene monododecyl ether [CH3(CH2)11(OCH2CH2)10OH], C12E10 in D2O solution have been analysed by small-angle neutron scattering (SANS) at different temperatures (30, 45 and 60°C) both in the presence and absence of sugars. The structural parameters like micelle shape and size, aggregation number and micellar density have been determined. It is found that the micellar structure significantly depends on the temperature and concentration of sugars. The micelles are found to be prolate ellipsoids at 30°C and the axial ratio of the micelle increases with the increase in temperature. The presence of lower concentration of sugar reduces the size of micelles and it grows at higher concentration of sugar. The structure of micelles is almost independent of the different types of sugars used.

  8. Liquid-liquid Extraction System Based on Non-ionic Surfactant-salt-H2O and Mechanism of Drug Extraction

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Extraction behavior of chlorpromazine hydrochloride (CPZ) and procaine hydro- chloride (PCN) in the system described in the title was studied.Research shows that the extraction efficiency of CPZ can amount to 96% by twice extraction,while that of PCN is 77%.This system produces the distribution coefficients (KD) of 12.3 and 2.6 respectively for CPZ and PCN.Extraction mechanism is deduced according to ultraviolet and molecular fluorescence spectra variation of the drugs in the system studied.

  9. Investigation on stabilization of CO2 foam by ionic and nonionic surfactants in presence of different additives for application in enhanced oil recovery

    Science.gov (United States)

    Kumar, Sunil; Mandal, Ajay

    2017-10-01

    Application of foam in upstream petroleum industry specifically in enhanced oil recovery (EOR) has gained significant interest in recent years. In view of this, an attempt has been paid to design the suitable foaming agents (foamer) by evaluating the influence of three surfactants, five nanoparticles and several additives. Experimental investigations have been carried out in order to examine the mechanism of foam generation in presence of sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB) and polysorbate 80 (Tween 80) as anionic, cationic and nonionic surfactants by using the CO2 as gaseous component. It has been found that ionic surfactants show the higher foam life compared to nonionic surfactant. Out of different nano particles used, namely alumina (Al2O3) zirconium oxide (ZrO2), calcium carbonate (CaCO3), boron nitride (BN) and silica (SiO2), boron nitride shows the maximum improvement of foam stability. The foam stability of surfactant-nanoparticles foam is further increased by addition of different additives viz. polymer, alcohol and alkali. The results show that, the designed foaming solution have nearly 2.5 times higher half-decay time (t1/2) compared to the simple surfactant system. Finally, it has been found that gas injection rate plays an important role in obtaining a uniform and stabilized foam.

  10. A coarse-grain molecular dynamics study of oil-water interfaces in the presence of silica nanoparticles and nonionic surfactants

    Science.gov (United States)

    Katiyar, Parul; Singh, Jayant K.

    2017-05-01

    In this work, we have studied the effect of hydrophilic silica nanoparticles (NPs), in the presence of nonionic surfactants (Triethylene glycol monododecyl ether and Tween 20), on the oil-water (n-octane-water, n-dodecane-water and n-hexadecane-water) interfacial tensions (IFTs) at 300 K, using coarse-grained molecular dynamics simulations based on the MARTINI force field. Simulation results indicate that silica NPs solely do not affect the IFT. However, the silica NPs may or may not increase the IFT of oil-water containing nonionic surfactant, depending on the tendency of the surfactant to adsorb on the surface of NPs. The adsorption occurs due to the formation of hydrogen bonds, and adsorption increases with a decrease in pH, as seen in experimental studies. In this work, we found that the oil-water IFT increases with an increasing amount of adsorption of the surfactant on NPs. At a fixed amount of adsorption of the surfactant on NPs, the IFT behavior is indifferent to the change in concentration of NPs. However, the IFT decreases with an increase in surfactant concentration. We present a detailed analysis of the density profile and intrinsic width of the interface. The IFT behavior is found to correlate extremely well with the intrinsic width of the interface. The current study provides an explanation for the increase in IFT observed in a recent experiment [N. R. Biswal et al., J. Phys. Chem. B 120, 7265-7274 (2016)] for various types of NPs and nonionic surfactant systems.

  11. Diversifying the solid state and lyotropic phase behavior of nonionic urea-based surfactants.

    Science.gov (United States)

    Fong, Celesta; Wells, Darrell; Krodkiewska, Irena; Weerawardeena, Asoka; Booth, Jamie; Hartley, Patrick G; Drummond, Calum J

    2007-09-13

    The solid state and lyotropic phase behavior of 10 new nonionic urea-based surfactants has been characterized. The strong homo-urea interaction, which can prevent urea surfactants from forming lyotropic liquid crystalline phases, has been ameliorated through the use of isoprenoid hydrocarbon tails such as phytanyl (3,7,11,15-tetramethyl-hexadecyl) and hexahydrofarnesyl (3,7,11-trimethyl-dodecyl) or the oleyl chain (cis-octadec-9-enyl). Additionally, the urea head group was modified by attaching either a hydroxy alkyl (short chain alcohol) moiety to one of the nitrogens of the urea or by effectively "doubling" the urea head group by replacing it with a biuret head group. The solid state phase behavior, including the liquid crystal-isotropic liquid, polymorphic, and glass transitions, is interpreted in terms of molecular geometries and probable hydrogen-bonding interactions. Four of the modified urea surfactants displayed ordered lyotropic liquid crystalline phases that were stable in excess water at both room and physiological temperatures, namely, 1-(2-hydroxyethyl)-1-oleyl urea (oleyl 1,1-HEU) with a 1D lamellar phase (Lalpha), 1-(2-hydroxyethyl)-3-phytanyl urea (Phyt 1,3-HEU) with a 2D inverse hexagonal phase (HII), and 1-(2-hydroxyethyl)-1-phytanyl urea (Phyt 1,1-HEU) and 1-(2-hydroxyethyl)-3-hexahydrofarnesyl urea (Hfarn 1,3-HEU) with a 3D bicontinuous cubic phase (QII). Phyt 1,1-HEU exhibited rich mesomorphism (QII1, QII2, Lalpha, LU, and HII), as did one other surfactant, oleyl 1,3-HEU (QII1, QII2, Lalpha, LU, and HII), in the study group. LU is an unusual phase which is mobile and isotropic but possesses shear birefringence, and has been very tentatively assigned as an inverse sponge phase. Three other surfactants exhibited a single lyotropic liquid crystalline phase, either Lalpha or HII, at temperatures >50 degrees C. The 10 new surfactants are compared with other recently reported nonionic urea surfactants. Structure-property correlations are examined for

  12. Desorption of hydrocarbon chains by association with ionic and nonionic surfactants under flow as a mechanism for enhanced oil recovery.

    Science.gov (United States)

    Terrón-Mejía, Ketzasmin A; López-Rendón, Roberto; Goicochea, Armando Gama

    2017-08-29

    The need to extract oil from wells where it is embedded on the surfaces of rocks has led to the development of new and improved enhanced oil recovery techniques. One of those is the injection of surfactants with water vapor, which promotes desorption of oil that can then be extracted using pumps, as the surfactants encapsulate the oil in foams. However, the mechanisms that lead to the optimal desorption of oil and the best type of surfactants to carry out desorption are not well known yet, which warrants the need to carry out basic research on this topic. In this work, we report non equilibrium dissipative particle dynamics simulations of model surfactants and oil molecules adsorbed on surfaces, with the purpose of studying the efficiency of the surfactants to desorb hydrocarbon chains, that are found adsorbed over flat surfaces. The model surfactants studied correspond to nonionic and cationic surfactants, and the hydrocarbon desorption is studied as a function of surfactant concentration under increasing Poiseuille flow. We obtain various hydrocarbon desorption isotherms for every model of surfactant proposed, under flow. Nonionic surfactants are found to be the most effective to desorb oil and the mechanisms that lead to this phenomenon are presented and discussed.

  13. Biosynthesis of Monascus pigments by resting cell submerged culture in nonionic surfactant micelle aqueous solution.

    Science.gov (United States)

    Wang, Bo; Zhang, Xuehong; Wu, Zhenqiang; Wang, Zhilong

    2016-08-01

    Growing cell submerged culture is usually applied for fermentative production of intracellular orange Monascus pigments, in which accumulation of Monascus pigments is at least partially associated to cell growth. In the present work, extractive fermentation in a nonionic surfactant micelle aqueous solution was utilized as a strategy for releasing of intracellular Monascus pigments. Those mycelia with low content of intracellular Monascus pigments were utilized as biocatalyst in resting cell submerged culture. By this means, resting cell submerged culture for production of orange Monascus pigments was carried out successfully in the nonionic surfactant micelle aqueous solution, which exhibited some advantages comparing with the corresponding conventional growing cell submerged culture, such as non-sterilization operation, high cell density (24 g/l DCW) leading to high productivity (14 AU of orange Monascus pigments at 470 nm per day), and recycling of cells as biocatalyst leading to high product yield (approximately 1 AU of orange Monascus pigments at 470 nm per gram of glucose) based on energy metabolism.

  14. Effect of inorganic additives on solutions of nonionic surfactants VI: Further cloud point relations.

    Science.gov (United States)

    Schott, H; Royce, A E

    1984-06-01

    Disperse dosage forms stabilized with nonionic surfactants frequently contain electrolytes as active ingredients or adjuvants. Salting out of the surfactants by these electrolytes may cause breakdown of the dosage forms. The cloud point of an aqueous solution of octoxynol 9 was used to measure the salt effects. Electrolytes which salt octoxynol 9 out lower its cloud point, while salting-in electrolytes raise it. The observed cloud point effects are discussed according to the mechanisms involved. Salting out by dehydration in competition with octoxynol 9 for the available water was observed with sulfate and phosphate anions, sodium, potassium, and ammonium tribasications, and the nonelectrolyte sorbitol. The extensive self-association of water by hydrogen bonds at and below room temperature weakens its solvent power. Ions which reduce this self-association, breaking the structure of water, increased the cloud point of octoxynol 9. Among them were the iodide, thiocyanate, and nitroprusside anions. Ions which tighten the structure of water and enhance its self-association salted the surfactant out, lowering its cloud point. Among these were the fluoride and hydroxide anions. Complex formation between the ether linkages of octoxynol 9 and the following cations increased its cloud point: hydrogen (from strong acids), silver, magnesium, and zinc. Including published data, the only cations which do not form complexes with polyoxyethylated surfactants (and are, therefore, unable to salt them in) were the alkali metal ions sodium, potassium, and cesium and the ammonium ion.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Synergistic effect of non-ionic surfactants Tween 80 and PEG6000 on cytotoxicity of insecticides.

    Science.gov (United States)

    Li, Diqiu; Wu, Xiwei; Yu, Xiaoqin; Huang, Qingchun; Tao, Liming

    2015-03-01

    The use of surfactants in the development of a suitable formulation for insecticides should improve the solubility behavior, the permeability and the efficiency against pests meanwhile decrease the toxic risks of insecticides on human health. Cytotoxicity of insecticides including abamectin, chlorfluazuron, hexaflumuron, chlorpyrifos, and tebufenozide was assessed on human HepG2 and lepidopteran Tn5B1-4 cells utilizing insecticide alone and in combination with nontoxic concentrations of nonionic surfactants Tween 80 and PEG6000. The results showed avermection revealed high cytotoxicity, chlorfluazuron and hexaflumuron possessed median cytotoxicity, and chlorpyrifos and tebufenozide had little cytotoxicity on HepG2 and Tn5B1-4 cells. The co-incubation with Tween 80 and PEG6000 powerfully counteracted the cytotoxicity of avermectin. Tween 80 enhanced, whereas PEG6000 compressed, the cytotoxicity of chlorfluazuron on Tn5B1-4 cells, and also improved a bit of the cytotoxicity of chlorpyrifos or tebufenozide on HepG2 cells. PEG6000 was more suitable to be used as surfactant in improving insecticide solubility and reducing the cytotoxicity. The present investigation demonstrates the necessity of utilizing surfactants to weaken the cytotoxicity of insecticides. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Adsorption of non-ionic surfactants on hydrophobic and hydrophilic carbon surfaces.

    Science.gov (United States)

    Soria-Sánchez, M; Maroto-Valiente, A; Guerrero-Ruiz, A; Nevskaia, D M

    2010-03-01

    The adsorption from aqueous solutions of a series of non-ionic surfactants (TX-114, TX-100, TX-165 and TX-305, where the ethoxylation degree is increasing in the series) on a non-microporous carbon surface, that is a high surface area graphite (GT), and on a mainly microporous activated carbon (NT) has been comparatively studied. Also the initially hydrophobic GT and NT surfaces have been modified by oxidation treatments in order to achieve partially hydrophilic carbon materials (GTox and NTox samples). The adsorption results reveal that for GT sample below the critical micellar concentrations (cmc) of surfactants practically the whole surface is covered by monomers. For NT there are steric hindrance limitations, so the surfactant molecules are adsorbed only on micropores of sizes larger than 8A. When oxygen surface groups are introduced on the carbonaceous surfaces, the adsorption behaviour is again different for both materials. Thus, for GTox the adsorbed amounts below the cmc decrease probably due to withdrawal effect of the oxygen surface groups. On the contrary, the adsorbed amounts above the cmc slightly increase with regard to bare graphite, possibly due to an improved formation of micelles. In the case of NTox the adsorbed uptakes below and above cmc increase remarkably in comparison with NT sample, which can be explained by some specific interactions of the surfactants molecules with oxygen surface groups inside the micropores.

  17. Technical and economic feasibility of soil flushing with non-ionic surfactant to remediate gas well condensate

    Energy Technology Data Exchange (ETDEWEB)

    Felske, D.; Morton, P.R. [EBA Engineering Consultants Ltd., Calgary, AB (Canada)

    2005-07-01

    The results of a feasibility study to assess the technical and economic viability of remediating condensate-impacted soils surrounding a main gas pipeline in northern Alberta by in situ flushing with non-ionic surfactant were presented. A commercially available non-ionic surfactant was evaluated for its solubility increasing properties as an economic means of solubilizing soil-bonded condensate. An injection-recovery well configuration was situated within the condensate spill pathway and was selected for a series of inter-well tests using surfactant injection and its recovery from a nearby pumped recovery well. Sodium bromide was used as a conservative tracer to assist in the selection of surfactant and solubilized hydrocarbon samples from the recovery well for laboratory analysis. Surfactant, hydrocarbon and tracer breakthrough curves were plotted for the recovered groundwater. Results enabled the quantification of surfactant effects on recovered groundwater. Findings demonstrated that the non-ionic surfactant achieved a significant solubilization and soil remediation of condensate at a more economic rate than bioventing, biosparging or soil vapour extraction when considered over the projected time, and attained all regulatory soil and groundwater quality remediation objectives.

  18. Adsorption of anionic and nonionic surfactant mixtures from synthetic detergents on soils.

    Science.gov (United States)

    Rao, Pinhua; He, Ming

    2006-05-01

    Adsorption of anionic surfactant (sodium dodecylbenzenesulfonate, SDBS) and nonionic surfactant (an alcohol ethoxylates with 12 carbons and 9 oxyethyl groups, A12E9) mixtures, widely used as the major constituents of synthetic detergents in China and become the most common pollutants in the environment, on soils was conducted to investigate the behavior of mixed surfactants in soils. The effects of addition order and mixing ratios of two surfactants, associated with pH and ion strength in solutions, on adsorptions were considered. The results show that saturated adsorption amount of SDBS and A12E9 on soils decreased respectively when A12E9 was added into soils firstly compared with that secondly, possibly resulting from the screening of A12E9 to part adsorption sites on soils and the hydrocarbon chain-chain interactions between SDBS and A12E9. The adsorption of SDBS and A12E9 on soils was enhanced each other at pre-plateau region of isotherms. At plateau region of isotherms, the adsorption of SDBS on soils decreased with the increase of molar fraction of A12E9 in mixed surfactant solutions, while that of A12E9 increased except the molar ratio of SDBS to A12E9 0.0:1.0. With the increase of pH in mixed surfactant solutions, adsorption amount of SDBS and A12E9 on soils decreased, respectively. The reduction of ion strength in soils resulted in the decrease of adsorption amount of SDBS and A12E9 on soils, respectively.

  19. Morphology and stability of CO2-in-water foams with nonionic hydrocarbon surfactants.

    Science.gov (United States)

    Adkins, Stephanie S; Chen, Xi; Chan, Isabel; Torino, Enza; Nguyen, Quoc P; Sanders, Aaron W; Johnston, Keith P

    2010-04-20

    The morphologies, stabilities, and viscosities of high-pressure carbon dioxide-in-water (C/W) foams (emulsions) formed with branched nonionic hydrocarbon surfactants were investigated by in situ optical microscopy and capillary rheology. Over two dozen hydrocarbon surfactants were shown to stabilize C/W foams with Sauter mean bubble diameters as low as 1 to 2 microm. Coalescence of the C/W foam bubbles was rare for bubbles larger than about 0.5 microm over a 60 h time frame, and Ostwald ripening became very slow. By better blocking of the CO(2) and water phases with branched and double-tailed surfactants, the interfacial tension decreases, the surface pressure increases, and the C/W foams become very stable. For branched surfactants with propylene oxide middle groups, the stabilities were markedly lower for air/water foams and decane-water emulsions. The greater stability of the C/W foams to coalescence may be attributed to a smaller capillary pressure, lower drainage rates, and a sufficient surface pressure and thus limiting surface elasticity, plus small film sizes, to hinder spatial and surface density fluctuations that lead to coalescence. Unexpectedly, the foams were stable even when the surfactant favored the CO(2) phase over the water phase, in violation of Bancroft's rule. This unusual behavior is influenced by the low drainage rate, which makes Marangoni stabilization of less consequence and the strong tendency of emerging holes in the lamella to close as a result of surfactant tail flocculation in CO(2). The high distribution coefficient toward CO(2) versus water is of significant practical interest for mobility control in CO(2) sequestration and enhanced oil recovery by foam formation.

  20. Effect of lipophilic tail architecture and solvent engineering on the structure of trehalose-based nonionic surfactant reverse micelles.

    Science.gov (United States)

    Shrestha, Lok Kumar; Sato, Takaaki; Dulle, Martin; Glatter, Otto; Aramaki, Kenji

    2010-09-23

    We use small-angle X-ray scattering and dynamic light scattering to investigate the structural and dynamical properties of trehalose polyisostearate, abbreviated as TQ-n (n = 3, 5, and 7), in different organic solvents, where n represents the number of isosterate chains per surfactant molecule. TQ-n spontaneously assembles into reverse micelles without addition of water at 25 °C. We found that for TQ-5 and TQ-7, steric hindrance of the lipophilic surfactant tail causes significant reduction of the aggregation number, whose scheme is clearly distinguished from the modification of the critical packing parameter. Increasing the hydrocarbon chain length of oils from octane to hexadecane favors one-dimensional micellar growth, leading to the formation of rodlike micelles due to different penetration tendencies of oils into the lipophilic shell of the surfactant. Subtle differences in solvent polarity also plays a crucial role in the micellar size, which is decreased when liquid paraffin is replaced with squalene. A further decrease is attained in more polar mixed triglyceride oils. A rising temperature also results in the same direction. The extrapolated structure factor to the zero scattering vector, S(q → 0), for the TQ-3/decane systems almost exactly follows that predicted for hard spheres, demonstrating that osmotic compressibility of the system is well explained if accounting for the excluded volume. However, we found that the effective diffusion coefficient decreases with surfactant concentration, which is an opposite trend to what is expected for hard spheres. This apparent contradiction is likely to be due to the occurrence of transient interdigitation between the lipophilic tails of neighboring reverse micelles at higher concentration. Our data highlight the relevance of the concept of "tunable reverse micellar geometry" in the novel trehalose-based nonionic surfactant binary mixtures, in which lipophilic tail architecture, solvent engineering, concentration

  1. Effects of nonionic surfactant lauryl alcohol ethoxylated on stratum corneum alternative model biomembranes evaluated by biophysical techniques

    OpenAIRE

    Baby, André R.; Lacerda, Áurea C. L.; Prestes, Paula S.; Velasco, María Valéria R.; Kawano, Yoshio; Kaneko,Telma Mary

    2011-01-01

    The influence of the nonionic surfactant lauryl alcohol ethoxylate with 12 moles ethylene oxide (LAE-12OE) was evaluated on the Stratum corneum model biomembrane (SCMM) of shed snake skin (Bothrops jararaca and Spilotes pullatus) through the biophysical techniques Fourier transform Raman spectroscopy (FT-Raman) and Fourier transform infrared photoacoustic spectroscopy (PAS-FTIR). The surfactant was used in aqueous solutions above and below the critical micelle concentration (cmc), 50.0 and 0....

  2. Mixing Effect of Polyoxyethylene-Type Nonionic Surfactants on the Liquid Crystalline Structures.

    Science.gov (United States)

    Kunieda; Umizu; Yamaguchi

    1999-10-01

    An effective cross-sectional area per surfactant molecule at hydrophobic interfaces of aggregates, a(S), in hexagonal (H(1)) and lamellar (L(alpha)) liquid crystals was calculated in homogeneous and mixed polyoxyethylene dodecyl ether systems as a function of polyoxyethylene (EO) chain length by means of small-angle X-ray scattering. The a(S) increases with increasing the EO chain length. The a(S) in the mixed surfactant system is considerably smaller than that in the single surfactant system, even if the average EO chain length is the same. The reduction of a(S) is larger than that predicted by ideal mixing of the surfactants. Moreover, if the EO chain lengths of the surfactants are more separated, the a(S) is smaller. The shapes of surfactant self-organizing structures may be governed by the balance of the attractive and the repulsive forces acting at the hydrophobic interfaces of the aggregates. According to this consideration, the mixing effect of surfactants with the different EO chain lengths on the a(S) in the L(alpha) phase was discussed. It is considered that the surfactant molecules are tightly packed in the aggregates since the reduction in repulsion force takes place in the excess EO chain part of the hydrophilic surfactant longer than the short EO chain of the lipophilic one. The lower surface tensions and the better stability of macroemulsions and the large solubilizing capacity of microemulsions result from the mixing effect. Copyright 1999 Academic Press.

  3. Enhanced solubilization and desorption of organochlorine pesticides (OCPs) from soil by oil-swollen micelles formed with a nonionic surfactant.

    Science.gov (United States)

    Zheng, Guanyu; Selvam, Ammaiyappan; Wong, Jonathan W C

    2012-11-06

    The effect of oil-swollen micelles formed with nonionic surfactant polyoxyethylene sorbitan monooleate (Tween 80), cosurfactant 1-pentanol, and linseed oil on the solubilization and desorption of organochlorine pesticides (OCPs) including DDT and γ-HCH from both loam soil and clay soil were investigated. Results showed that the solubilizing capacities of oil-swollen micelles were dependent on the critical micelle concentration (CMC) of Tween 80. Once the concentrations of oil-swollen micelles exceeded the CMC of Tween 80, the oil-swollen micelles exhibited much higher solubilizing capacity than empty Tween 80 micelles for the two OCPs. Desorption tests revealed that oil-swollen micelles could successfully enhance desorption of OCPs from both loam soil and clay soil. However, compared with the efficiencies achieved by empty Tween 80 micelles, oil-swollen micelles exhibited their superiority to desorb OCPs only in loam soil-water system while was less effective in clay soil-water system. Distribution of Tween 80, 1-pentanol and linseed oil in soil-water system revealed that the difference in the sorption behavior of linseed oil onto the two soils is responsible for the different effects of oil-swollen micelles on the desorption of OCPs in loam soil and clay soil systems. Therefore, oil-swollen micelles formed with nonionic surfactant Tween 80 are better candidates over empty micelle counterparts to desorb OCPs from soil with relatively lower sorption capacity for oil fraction, which may consequently enhance the availability of OCPs in soil environment during remediation processes of contaminated soil.

  4. A limitation of the Microtox{reg_sign} test for toxicity measurements of nonionic surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Sherrard, K.B.; Marriott, P.J.; McCormick, M.J. [Royal Melbourne Inst. of Tech. (Australia). Dept. of Applied Chemistry; Millington, K. [CSIRO, Belmont (Australia). Div. of Wool Technology

    1996-07-01

    Qualitative and quantitative analysis of the components of wastewaters is a necessary step towards determining the nature of aqueous effluents. However, toxicity levels of the effluents and receiving waters should also be determined to obtain a more comprehensive understanding of the effects the discharges may have on aquatic environments. The Microtox{reg_sign} test was successfully used to measure EC50 values of nonionic polyethoxylate surfactants. However, toxicity measurements of real samples that contain surfactants above a particular concentration, termed the critical toxicity concentration (CTC) are not valid. These samples require dilution before the test is performed, and because the relationship between toxicity and concentration is not linear above the CTC, the EC50 cannot be extrapolated back to give the toxicity of the original concentrated sample and a true estimation of toxicity is therefore not possible. This phenomenon may be related to the minimum surface tension requirement of the bacteria or other physical properties of the surfactant such as the tendency to assemble at interfaces and surfaces and the tendency to form micelles.

  5. Experimental investigation of wettability alteration on residual oil saturation using nonionic surfactants: Capillary pressure measurement

    Directory of Open Access Journals (Sweden)

    Masoud Amirpour

    2015-12-01

    Full Text Available Introducing the novel technique for enhancing oil recovery from available petroleum reservoirs is one of the important issues in future energy demands. Among of all operative factors, wettability may be the foremost parameter affecting residual oil saturation in all stage of oil recovery. Although wettability alteration is one of the methods which enhance oil recovery from the petroleum reservoir. Recently, the studies which focused on this subject were more than the past and many contributions have been made on this area. The main objective of the current study is experimentally investigation of the two nonionic surfactants effects on altering wettability of reservoir rocks. Purpose of this work is to change the wettability to preferentially the water-wet condition. Also reducing the residual oil saturation (Sor is the other purpose of this work. The wettability alteration of reservoir rock is measured by two main quantitative methods namely contact angle and the USBM methods. Results of this study showed that surfactant flooding is more effective in oil-wet rocks to change their wettability and consequently reducing Sor to a low value. Cedar (Zizyphus Spina Christi is low priced, absolutely natural, and abundantly accessible in the Middle East and Central Asia. Based on the results, this material can be used as a chemical surfactant in field for enhancing oil recovery.

  6. Using Nonionic Surfactants for Production of Semiconductor-type Carbon Nanotubes by Gel-based Affinity Chromatography

    Directory of Open Access Journals (Sweden)

    Varun Shenoy Gangoli

    2014-07-01

    characterization of the particulate suspension. Semiconductor- type SWCNTs are recovered in solid form by evaporating the suspension fluid, and heating the dried sample in air to a temperature just above the Pluronic decomposition temperature. Using Pluronic and other nonionic-type surfactants can aid the scalability of the chromatographic production of semiconducting SWCNT samples.

  7. SURFACE MODIFICATION OF POLYPROPYLENE MICROPOROUS MEMBRANES BY THE ADSORPTION OF NON-IONIC SURFACTANTS

    Institute of Scientific and Technical Information of China (English)

    Ya-jie Xie; Hai-yin Yu; Zhi-kang Xu

    2006-01-01

    Surface modification by physical adsorption of a series of non-ionic surfactants including Tween 20, Tween 40,Tween 60, Tween 80 and Tween 85, was accomplished on polypropylene microporous hollow fiber and flat membranes. The adsorption curve of the membrane surface was analyzed by weight measurements and the typical results showed a twoplatform character similarly. Differences in the degree and curve shape of adsorption resulting from such factors as concentration, temperature, as well as water cleaning time were observed for Tween 85 among other Tweens. Attenuated total reflection - Fourier transform infrared spectroscopy analysis and field emission scanning electron microscopy observation showed that the adsorption of Tween on polypropylene microporous membrane (PPMM) is effective and occurs mainly in the pores of PPMMs at low adsorption amount, and on the membrane surface also at high adsorption value.

  8. Ludwig-Soret effect of non-ionic surfactant aqueous solution studied by beam deflection method

    Science.gov (United States)

    Maeda, Kousaku; Kita, Rio; Shinyashiki, Naoki; Yagihara, Shin

    2013-02-01

    We have studied the thermal diffusion of non-ionic surfactant aqueous solutions by a beam deflection method. The thermal diffusion of pentaethylene glycol monododecyl ether (C12E5) and hexaethylene glycol monododecyl ether (C12E6) is studied in the concentration range of 1.0-99.0 wt% and in the temperature range of 20.0-35.0 °C. A stable temperature gradient is applied to the solution, where solute molecules shift to the cold side of the solution for lowconcentration samples. The concentration dependence of the Soret coefficient ST of the C12E6 aqueous solution shows a sign inversion behavior. At all concentrations, the developed concentration gradient is proportionally related to the applied temperature gradient. The results confirm that the magnitude of ST has no temperature gradient dependence under the studied experimental conditions.

  9. Effect of the Presence of Nonionic Surfactant Brij35 on the Mobility of Metribuzin in Soil

    Directory of Open Access Journals (Sweden)

    Eman M. ElSayed

    2013-04-01

    Full Text Available Given the water scarcity becoming endemic to a large portion of the globe, arid region irrigation has resorted to the use of treated, partially treated, or even untreated wastewaters. Such waters contain a number of pollutants, including surfactants. Applied to agricultural lands, these surfactants could affect the fate and transport of other chemicals in the soil, particularly pesticides. A field lysimeter study was undertaken to investigate the effect of nonionic surfactant, Brij35, on the in-soil fate and transport of a commonly used herbicide, metribuzin [4-amino-6-tert-butyl-3-(methylthio-1,2,4-triazin-5(4H-one]. Nine PVC lysimeters, 1.0 m long × 0.45 m diameter, were packed with a sandy soil to a bulk density of 1.35 mg m−3. Antibiotic-free cattle manure was applied (10 mg ha−1 at the surface of the lysimeters. Metribuzin was then applied to the soil surface of all lysimeters at a rate of 1.00 kg a.i. ha−1. Each of three aqueous Brij35 solutions, 0, 0.5 and 5 mg L−1 (i.e., “good”, “poor” and “very poor” quality irrigation water were each applied to the lysimeters in triplicate. Analysis for metribuzin residues in samples of both soil and leachate, collected over a 90-day period, showed the surfactant Brij35 to have increased the mobility of metribuzin in soil, indicating that continued use of poor quality water could influence pesticide transport in agricultural soils, and increase the risk of groundwater contamination.

  10. Development of Drug Loaded Nanoparticles Binding to Hydroxyapatite Based on a Bisphosphonate Modified Nonionic Surfactant

    Directory of Open Access Journals (Sweden)

    Jiabin Zhang

    2015-01-01

    Full Text Available This study aimed at development of drug loaded nanoparticles which could bind to hydroxyapatite (HA to construct drug or growth factor releasing bone graft substitutes. To this end, the terminal hydroxyl group of a nonionic surfactant Brij 78 (polyoxyethylene (20 stearyl ether was first modified with pamidronate (Pa. Using Pa-Brij 78 as both a surfactant and an affinity ligand to HA, three different Pa surface functionalized nanoparticles were prepared, named as solid lipid nanoparticles (Pa-SNPs, nanoemulsions (Pa-NEMs, and PLGA nanoparticles (Pa-PNPs. A model drug curcumin was successfully encapsulated in the three nanoparticles. The sizes of Pa-NEM and Pa-PNP were around 150 nm and the size of Pa-SNP was around 90 nm with polydispersity indexes (PDIs less than 0.20. Drug encapsulation efficiencies of the three nanoparticles were all greater than 85%. Furthermore, the order of binding affinity of the nanoparticles to HA was Pa-PNP>Pa-NEM=Pa-SNP. After lyophilization, the sizes of the three nanoparticles were increased about 0.5–2.0-fold but their binding affinities to HA were almost the same as the fresh prepared nanoparticles. In conclusion, a Pa-modified Brij 78 was synthesized and used for fabrication of a series of drug loaded nanoparticles to construct drug-eluting HA-based bone graft substitutes.

  11. Prediction on Critical Micelle Concentration of Nonionic Surfactants in Aqueous Solution: Quantitative Structure-Property Relationship Approach

    Institute of Scientific and Technical Information of China (English)

    王正武; 黄东阳; 宫素萍; 李干佐

    2003-01-01

    In order to predict the critical micelle concentration (cmc) of nonionic surfactants in aqueous solution, a quantitative structure-property relationship (QSPR) was found for 77 nonionic surfactants belonging to eight series. The best-regressed model contained four quantum-chemical descriptors, the heat of formation (△H), the molecular dipole moment (D), the energy of the lowest unoccupied molecular orbital (ELUMO) and the energy of the highest occupied molecular orbital (EHOMO) of the surfactant molecule; two constitutional descriptors, the molecular weight of surfactant (M) and the number of oxygen and nitrogen atoms (nON ) of the hydrophilic fragment of surfactant molecule; and one topological descriptor, the Kier & Hall index of zero order (KH0) of the hydrophobic fragment of the surfactant. The established general QSPR between Ig (cmc) and the descriptors produced a relevant coefficient of multiple determination: R2=0.986. When cross terms were considered, the corresponding best model contained five descriptors ELUMO, D,KH0, M and a cross term nON·KH0, Which also produced the same coefficient as the seven-parameter model.

  12. Effect of nonionic surfactant addition on Pyrex glass ablation using water-assisted CO2 laser processing

    Science.gov (United States)

    Chung, C. K.; Liao, M. W.; Lin, S. L.

    2010-04-01

    Pyrex glass etching using laser ablation is an important technology for the microfluid application to lab-on-a-chip devices but suffers from the formation of surface crack. In this article, the addition of nonionic surfactant to water for glass ablation using water-assisted CO2 laser processing (WACLAP) has been investigated to enhance ablation rate and to eliminate conventional surface defects of cracks in air. WACLAP for Pyrex glass ablation can reduce thermal-stress-induced crack with water cooling and hydrophilic nonionic surfactant to water can enhance ablation performance. Compared to pure water, the 15% weight percent Lauramidopropyl Betaine surfactant solutions for WACLAP can enhance ablation rate from 13.6 to 25 μm/pass of Pyrex glass ablation at a linear laser energy density of 2.11 J/cm, i.e., 24 W power, 114 mm/s scanning speed, and obtain through-wafer etching at 3.16 J/cm for 20 passes without cracks on the surface. Effect of surfactant concentration and linear energy density on WACLAP was also examined. The possible mechanism of surfactant-enhanced phenomenon was discussed by the Newton’s law of viscosity of surfactant solution.

  13. Effects of different nonionic surfactants on in vitro fermentation characteristics of cereal straws.

    Science.gov (United States)

    Cong, Z H; Tang, S X; Tan, Z L; Sun, Z H; Zhou, C S; Han, X F; Wang, M; Ren, G P

    2009-03-01

    The effects of 3 nonionic surfactants (NIS), including alkyl polyglucoside (APG), sorbitan trioleate (Span85), and polyoxyethylene sorbitan monostearate (Tween80), on in vitro fermentation characteristics of maize stover, rice straw, and wheat straw were examined using an in vitro gas production technique. Four levels each of APG, Span85, and Tween80 [0, 0.02, 0.05, and 0.1% (vol/vol) of incubation solution] were tested in a 4 x 4 x 4 factorial arrangement. The NIS generally increased the in vitro maximal gas production (A), but decreased the lag time of cereal straws. The effects of NIS on the rate of gas production (B) were related to the surfactant type and fermented substrate. The NIS generally increased IVDMD and in vitro OM disappearance (IVOMD) of cereal straws, but responses were dose dependent. The NIS increased total VFA concentration of in vitro fermentation supernatant for maize stover and wheat straw, but decreased total VFA concentration for rice straw. The effects of NIS on the molar proportions of acetate, propionate, and butyrate were dependent on the dose and type of NIS and on fermented substrate. Several interactive effects were noted between or among 3 surfactants (APG, Span85, and Tween80) on in vitro gas production variables, IVD-MD, IVOMD, and VFA for each straw; the optimal combinations of 2 or 3 types of NIS were determined according to the responses of IVDMD and IVOMD to NIS addition. The results of this study suggest that NIS may improve in vitro fermentation of low quality roughages and have potential application as feed additives in ruminant production.

  14. Structure-interfacial properties relationship and quantification of the amphiphilicity of well-defined ionic and non-ionic surfactants using the PIT-slope method.

    Science.gov (United States)

    Ontiveros, Jesús F; Pierlot, Christel; Catté, Marianne; Molinier, Valérie; Salager, Jean-Louis; Aubry, Jean-Marie

    2015-06-15

    The Phase Inversion Temperature of a reference C10E4/n-Octane/Water system exhibits a quasi-linear variation versus the mole fraction of a second surfactant S2 added in the mixture. This variation was recently proposed as a classification tool to quantify the Hydrophilic-Lipophilic Balance (HLB) of commercial surfactants. The feasibility of the so-called PIT-slope method for a wide range of well-defined non-ionic and ionic surfactants is investigated. The comparison of various surfactants having the same dodecyl chain tail allows to rank the polar head hydrophilicity as: SO3Na⩾SO4Na⩾NMe3Br>E2SO3Na≈CO2Na⩾E1SO3Na⩾PhSO3Na>Isosorbide(exo)SO4Na≫IsosorbideendoSO4Na≫E8⩾NMe2O>E7>E6⩾Glucosyl>E5⩾Diglyceryl⩾E4>E3>E2≈Isosorbide(exo)>Glyceryl>Isosorbide(endo). The influence on the surfactant HLB of other structural parameters, i.e. hydrophobic chain length, unsaturation, replacement of Na(+) by K(+) counterion, and isomerism is also investigated. Finally, the method is successfully used to predict the optimal formulation of a new bio-based surfactant, 1-O-dodecyldiglycerol, when performing an oil scan at 25 °C.

  15. Aqueous Foams Stabilized by Hydrophilic Silica Nanoparticles via In-Situ Physisorption of Nonionic TX100 Surfactant

    Directory of Open Access Journals (Sweden)

    Suriatie Yusuf

    2013-01-01

    Full Text Available This paper present the study of aqueous CO foam prepared 2 by a mixtures hydrophilic silica nanoparticles and non-ionic Triton X100, TX100, surfactant. The synergistic effects of the mixture on stabilizing the CO2 foam were inferred into few key parameters namely; particles and surfactant concentration, adsorption of surfactant onto the particles via surface tension and adsorption isotherm, foam lifetime and, the size of the bubbles produced. It was found that the adsorption behaviour of TX100 on silica surface exhibit a particular characteristics depend on the concentration of silica, high total surface area available leads to high adsorptionof surfactant molecules. The synergetic performance of silica/TX100 in stabilizing foam can be observed at low (0.01% and intermediate (0.1% concentration of TX100. Lower concentration required low silica concentration while the intermediate concentration required high silica fraction in the dispersion to stabilize the foam.

  16. Study on dynamics characteristics of wet air oxidation of non-ionic surfactants

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Wet air oxidation is an effective method to deal with highly concentrated nondegradable emulsification wastewater which contains non-ionic surfactants. This article illustrates our investigation on dynamic characteristics of wet air oxidation of typical non-ionic surfactants like polyether, phenol ether and widely used alcohol ether. The experimental results indicated that the oxidation rate of polyether, phenol ether and alcohol ether obviously ascended as the temperature rose. A good oxidation effect was available at 240℃. The TOC removal rate could reach 88.0%, 94% and 91.5%, after 125 min reaction. Alcohol ether was prone to an easier oxidation compared with polyether and phenol ether when the temperature was 220℃ or below. The oxidation rate of alcohol ether was higher than that of polyether at 160℃, while the oxidation rate of polyether was higher than that of phenol ether between 180℃ and 220℃. During the later period of the reaction at 240℃, the rate of phenol ether was higher than that of alcohol ether, which was still higher than that of polyether. Partitioned first order kinetics model analy-sis showed that the apparent activation energy of alcohol ether was lower than that of both polyether and phenol ether in the leading stage and lagging stage, and it was easy to acquire a higher oxidation rate for alcohol ether at low temperature. Three parameter general dynamics model analyses showed that the reason why the oxidation rate of polyether was lower than that of alcohol ether was that the oxidation of polyether was more apt to be converted to intermediate production than that of alcohol ether, whereas between 200℃ and 220℃, the direct oxidation rate of polyether and the oxidation rate of intermediate product were obviously lower than that of alcohol ether. The apparent activation energy of direct and indirect oxidation of polyether was 43.37 and 60.45 kJ?mol?1, respectively, while the corre-sponding apparent activation energy of alcohol

  17. Study on dynamics characteristics of wet air oxidation of non-ionic surfactants

    Institute of Scientific and Technical Information of China (English)

    ZENG XinPing; TANG WenWei; ZHAO JianFu; GU GuoWei

    2008-01-01

    Wet air oxidation is an effective method to deal with highly concentrated nondegradable emulsification wastewater which contains non-ionic surfactants. This article illustrates our investigation on dynamic characteristics of wet air oxidation of typical non-ionic surfactants like polyether, phenol ether and widely used alcohol ether. The experimental results indicated that the oxidation rate of polyether, phenol ether and alcohol ether obviously ascended as the temperature rose. A good oxidation effect was available at 240℃. The TOC removal rate could reach 88.0%, 94% and 91.5%, after 125 min reaction. Alcohol ether was prone to an easier oxidation compared with polyether and phenol ether when the temperature was 220℃ or below. The oxidation rate of alcohol ether was higher than that of polyether at 160℃, while the oxidation rate of polyether was higher than that of phenol ether between 180℃ and 220℃. During the later period of the reaction at 240℃, the rate of phenol ether was higher than that of alcohol ether, which was still higher than that of polyether. Partitioned first order kinetics model analysis showed that the apparent activation energy of alcohol ether was lower than that of both polyether and phenol ether in the leading stage and lagging stage, and it was easy to acquire a higher oxidation rate for alcohol ether at low temperature. Three parameter general dynamics model analyses showed that the reason why the oxidation rate of polyether was lower than that of alcohol ether was that the oxidation of polyether was more apt to be converted to intermediate production than that of alcohol ether, whereas between 200℃ and 220℃, the direct oxidation rate of polyether and the oxidation rate of intermediate product were obviously lower than that of alcohol ether. The apparent activation energy of direct and indirect oxidation of polyether was 43.37 and 60.45 kJ·mol-1, respectively, while the corresponding apparent activation energy of alcohol

  18. Interaction between cationic and conventional nonionic surfactants in the mixed micelle and monolayer formed in aqueous medium

    Directory of Open Access Journals (Sweden)

    Nabel A. Negm

    2011-01-01

    Full Text Available Mixed micellization and surface properties of cationic and nonionic surfactants dimethyl decyl-, tetradecyl- and hexadecyl phosphineoxide mixtures are studied using conductivity and surface tension measurements. The models of Rubingh, Rosen, and Clint, are used to obtain the interaction parameter, minimum area per molecule, mixed micelle composition, free energies of mixing and activity coefficients. The micellar mole fractions were always higher than ideal values indicating high contributions of cationics in mixed micelles. Activity coefficients were less than unity indicating synergism in micelles. The negative free energies of mixing showed the stability of the surfactants in the mixed micelles.

  19. Dynamics of falling droplet and elongational properties of dilute nonionic surfactant solutions with drag-reducing ability

    Science.gov (United States)

    Tamano, Shinji; Ohashi, Yota; Morinishi, Yohei

    2017-05-01

    The dynamics of the falling droplet through a nozzle for dilute nonionic surfactant (oleyl-dimethylamine oxide, ODMAO) aqueous solutions with viscoelastic and drag-reducing properties were investigated at different concentrations of ODMAO solutions Cs = 500, 1000, and 1500 ppm by weight. The effects of the flow rate and tube outer diameter on the length of the filament, which was the distance between the tube exit and the lower end of a droplet at the instant when the droplet almost detached from the tube, were clarified by flow visualization measurements by a high-speed video camera. Two types of breaking-off processes near the base of the droplet and within the filament were classified by the Ohnesorge number Oh and the Weber number We. In the regime of the higher Oh and We, the length of the filament became drastically larger at Cs = 1000 and 1500 ppm, whose high spinnability represented the strong viscoelasticity of ODMAO solutions. In the case where the filament was broken up near the lower end of the neck and thinning in time, the thinning of the diameter of the filament was measured by a light-emitting diode micrometer. As for the elasto-capillary thinning of dilute nonionic surfactant solutions, the initial necking process was similar to that of Newtonian fluids and then followed the exponential thinning like polymer solutions. The apparent elongational viscosity of the dilute nonionic surfactant solution was evaluated in the elasto-capillary thinning regime, in which the elongation rate was almost constant. At Cs = 1000 and 1500 ppm, the Trouton ratio, which was the ratio of the apparent elongational viscosity to the shear viscosity, was found to be several orders of magnitude larger than that of Newtonian fluids, while the shear viscosity measured by the capillary viscometer was almost the same order of the Newtonian fluids. The higher elongational property would be closely related to the higher drag-reducing ability of dilute nonionic surfactant

  20. Enthalpy of interaction and binding isotherms of non-ionic surfactants onto micellar amphiphilic polymers (amphipols).

    Science.gov (United States)

    Diab, C; Winnik, F M; Tribet, C

    2007-03-13

    The interactions in water between short amphiphilic macromomolecules, known as amphipols, and three neutral surfactants (detergents), dodecylmaltoside (DM), n-octylthioglucoside (OTG), and n-octyltetraethyleneoxide (C8E4), have been assessed by static and dynamic light-scattering (SLS and DLS), capillary electrophoresis (CE), and isothermal titration calorimetry (ITC). The amphipols selected are random copolymers of the hydrophobic n-octylacrylamide (25-30 mol %), a charged hydrophilic monomer, either acrylic acid ( approximately 35 mol %) or a phosphorylcholine-modified acrylamide (40-70 mol %), and, optionally, N-isopropylacrylamide (30-40 mol %). In water, the copolymers form micelles of small size (hydrodynamic radius: approximately 5 nm). Neutral surfactants, below their critical micellar concentration (cmc), form mixed micelles with the amphipols irrespective of the chemical structure of the detergent or the polymer. The fraction of detergent in the surfactant/polymer complexes increases significantly (cooperatively) as the surfactant concentration nears the cmc. The ITC data, together with data gathered by CE, were fitted via a regular mixing model, which allowed us to predict the detergent concentration in equilibrium with complexes and the heat evolved upon transfer of detergent from water into a mixed surfactant/polymer complex. The enthalpy of transfer was found to be almost equal to the enthalpy of micellization, and the regular mixing model points to a near-ideal mixing behavior for all systems. Amphipols are promising tools in biochemistry where they are used, together with neutral surfactants, for the stabilization and handling of proteins. This study provides guidelines for the optimization of current protein purification protocols and for the formulations of surfactant/polymer systems used in pharmaceutics, cosmetics, and foodstuffs.

  1. Effects of the nonionic surfactant tween 80 on microbial reductive dechlorination of chlorinated ethenes.

    Science.gov (United States)

    Amos, Benjamin K; Daprato, Rebecca C; Hughes, Joseph B; Pennell, Kurt D; Löffler, Frank E

    2007-03-01

    Recent field studies have indicated synergistic effects of coupling microbial reductive dechlorination with physicochemical remediation (e.g., surfactant flushing) of dense nonaqueous phase liquid (DNAPL) source zones. This study explored chlorinated ethene (e.g., tetrachloroethene [PCE]) dechlorination in the presence of 50-5000 mg/L Tween 80, a nonionic surfactant employed in source zone remediation. Tween 80 did not inhibit dechlorination by four pure PCE-to-cis-1,2-dichloroethene (cis-DCE) or PCE-to-trichloroethene (TCE) dechlorinating cultures. In contrast, cis-DCE-dechlorinating Dehalococcoides isolates (strain BAV1 and strain FL2) failed to dechlorinate in the presence of Tween 80. Bio-Dechlor INOCULUM (BDI), a PCE-to-ethene dechlorinating consortium, produced cis-DCE in the presence of Tween 80, further suggesting that Tween 80 inhibits dechlorination by Dehalococcoides organisms. Quantitative real-time PCR analysis applied to BDI revealed that the number of Dehalococcoides cells decayed exponentially (R(2) = 0.85) according to the Chick-Watson disinfection model (pseudo first-order decay rate of 0.13+/-0.02 day(-1)) from an initial value of 6.6 +/-1.5 x 10(8) to 1.3+/-0.8 x 10(5) per mL of culture after 58 days of exposure to 250 mg/L Tween 80. Although Tween 80 exposure prevented ethene formation and reduced Dehalococcoides cell numbers, Dehalococcoides organisms remained viable, and dechlorination activity pist cis-DCE was recovered following the removal of Tween 80. These findings suggest that sequential Tween 80 flushing followed by microbial reductive dechlorination is a promising strategy for remediation of chlorinated ethene-impacted source zones.

  2. Phase Behaviors of Ternary Systems Formed by Nonionic Surfactant, Ionic Liquid and Water%非离子表面活性剂与离子液体、水三组分体系的相行为

    Institute of Scientific and Technical Information of China (English)

    庄文昌; 王欲晓; 袁影华

    2012-01-01

    Ionic liquids have attracted much attention due to the rise of green chemistry and their own advantages. In this paper, phase behaviors of ternary systems formed by nonionic amphiphilic molecules, ionic liquid and water are researched on by polarizing microscopy and small angle X-ray scattering. Furthermore, ordered structures are also analyzed.%离子液体因绿色化学的兴起并凭借自身的优点而备受关注.文章采用两种不同的离子液体与水构成双极性溶剂,研究了非离子表面活性剂C12E4在其中的聚集行为,同时利用偏光显微镜和小角X射线散射技术对所形成的有序结构进行了分析.

  3. Synthesis and characterization of high molecular weight hydrophobically modified polyacrylamide nanolatexes using novel nonionic polymerizable surfactants

    Directory of Open Access Journals (Sweden)

    A.M. Al-Sabagh

    2013-12-01

    Full Text Available In this article, nine hydrophobically modified polyacrylamides (HM-PAM nanolatexes, were synthesized by copolymerizing the acrylamide monomer and novel polymerizable surfactants (surfmers. The reaction was carried out by inverse microemulsion copolymerization technique. The copolymerization was initiated by redox initiators composed of potassium peroxodisulphate and sodium bisulfite. The emulsion was stabilized using mixed tween 85 and span 80 as nonionic emulsifiers. The prepared HM-PAMs were classified into three groups according to the surfmers used in the copolymerization. The chemical structures of the prepared HM-PAMs were confirmed by FT-IR, 1H NMR and 13C NMR. The thermal properties were estimated with the thermal gravimetric analysis (TGA. The size and morphology of the prepared latexes were investigated by the dynamic light scattering (DLS and the High Resolution Transmission Electron Microscope (HRTEM. Finally, the molecular weights of the prepared copolymers were determined by the GPC and the viscosity average molecular weight method. They were situated between 1.58 × 106 and 0.89 × 106.

  4. Application of lactobionic acid and nonionic surfactants as solubilizing agents for parenteral formulation of clarithromycin

    Directory of Open Access Journals (Sweden)

    Mohammad-Hosein Zarrintan

    2012-06-01

    Full Text Available Purpose: The purpose of this paper is to enhance the solubility of clarithromycin (CLR using nonionic surfactants and some type of acids for preparation of the new formulations. Methods: Myrj 52 and chremophor (2.5 and 5% w/v were used in two concentrations. To investigate solubility, the formulations were shaken for 48 hours at room temperature. For stability test, lyophilized samples were maintained in refrigerator at 4° C, and in oven at 40° C. Drug analysis was performed by reverse phase high performance liquid chromatography (HPLC with ultraviolet detection. Results: Solubility tests indicated that lactobionic acid was the most effective to increase clarithromycin solubility and chremophor showed higher enhancing effect than myrj 52 on CLR solubility. The stability tests results also confirmed that shelf-lives of all formulations have been the equivalent to 24 months. Conclusion: On the whole, formulations described in this article may be very suitable for industrial-scale manufacturing and clinical application.

  5. Effects of pH and cationic and nonionic surfactants on the adsorption of pharmaceuticals to a natural aquifer material.

    Science.gov (United States)

    Hari, Ajai C; Paruchuri, Rajiv A; Sabatini, David A; Kibbey, Tohren C G

    2005-04-15

    A wide range of pharmaceutical compounds have been identified in the environment, and their presence is a topic of growing concern, both for human and ecological health. Adsorption to aquifer materials and sediments is an important factor influencing the fate and transport of pharmaceutical compounds in the environment. Surfactants and other amphiphiles are known to influence the adsorption of many compounds and may be present in the environment from wastewaters or other sources. The work described here examines the adsorption of four pharmaceutical compounds, acetaminophen, carbamazepine, nalidixic acid, and norfloxacin, in the presence of a natural aquifer material. Adsorption was studied as a function of pH and in the presence and absence of two surfactants, cetylpyridinium chloride (CPC), a cationic surfactant, and Tergitol NP9, an ethoxylated nonionic surfactant. In the absence of surfactants, results indicate a 1-2 orders of magnitude variation in adsorption affinity with changing pH for each of the two quinolone pharmaceuticals (nalidixic acid and norfloxacin) but no measurable adsorption for carbamazepine or acetaminophen. In the presence of surfactants, adsorption of acetaminophen and carbamazepine was enhanced to extents consistent with compound hydrophobicity, while adsorption of nalidixic acid and norfloxacin was not. At high pH values, the anionic species of nalidixic acid exhibited enhanced adsorption in the presence of the cationic surfactant, CPC.

  6. Screening of mixed surfactant systems: Phase behavior studies and CT imaging of surfactant-enhanced oil recovery experiments

    Energy Technology Data Exchange (ETDEWEB)

    Llave, F.M.; Gall, B.L.; Lorenz, P.B.; Cook, I.M.; Scott, L.J.

    1993-11-01

    A systematic chemical screening study was conducted on selected anionic-nonionic and nonionic-nonionic systems. The objective of the study was to evaluate and determine combinations of these surfactants that would exhibit favorable phase behavior and solubilization capacity. The effects of different parameters including (a) salinity, (b) temperature, (c) alkane carbon number, (c) hydrophilic/lipophilic balance (HLB) of nonionic component, and (d) type of surfactant on the behavior of the overall chemical system were evaluated. The current work was conducted using a series of ethoxylated nonionic surfactants in combinations of several anionic systems with various hydrocarbons. Efforts to correlate the behavior of these mixed systems led to the development of several models for the chemical systems tested. The models were used to compare the different systems and provided some guidelines for formulating them to account for variations in salinity, oil hydrocarbon number, and temperature. The models were also evaluated to determine conformance with the results from experimental measurements. The models provided good agreement with experimental results. X-ray computed tomography (CT) was used to study fluid distributions during chemical enhanced oil recovery experiments. CT-monitored corefloods were conducted to examine the effect of changing surfactant slug size injection on oil bank formation and propagation. Reducing surfactant slug size resulted in lower total oil production. Oil recovery results, however, did not correlate with slug size for the low-concentration, alkaline, mixed surfactant system used in these tests. The CT measurements showed that polymer mobility control and core features also affected the overall oil recovery results.

  7. Cloud Point Extraction of Toxic Reactive Black 5 Dye from Water Samples Using Triton X-100 as Nonionic Surfactant

    Directory of Open Access Journals (Sweden)

    Raziyeh Mousavi

    2011-01-01

    Full Text Available A surfactant mediated cloud point extraction (CPE procedure has been developed to remove color from wastewater containing reactive black 5, using triton x-100 (TX-100 as non-ionic surfactant. The effects of the concentration of the surfactant, pH, temperature and salt concentration on the different concentrations of dye have been studied and optimum conditions were obtained for the removal of reactive black 5 (RB 5. The concentration of RB 5 in the dilute phase was measured using UV-Vis spectrophotometer. It was found that the separation of phases was complete and the recovery of RB 5 was very effective in the presence of NaCl as an electrolyte. The results showed that up to 600 mg L-1 of RB 5 can quantitatively be removed (>97% by cloud point extraction procedure in a single extraction using optimum conditions.

  8. Determination of the free energy of adsorption on carbon blacks of a nonionic surfactant from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Garcia, C.M.; Gonzalez-Martin, M.L.; Gomez-Serrano, V.; Bruque, J.M.; Labajos-Broncano, L.

    2000-04-18

    The adsorption of a nonionic surfactant (Triton X-100) from aqueous solutions has been studied on six carbon blacks with very different specific surface areas. The surface area occupied per surfactant molecule on the carbon black surface and the free energy of adsorption have been evaluated from the adsorption isotherms. Also, the free energy of adsorption has been determined from the free energy of interaction between adsorbent and adsorbate through water. The results obtained from both methods are in good agreement. They indicate that adsorption progresses following two different processes: the first one deals with the direct interaction between carbon black surface and adsorbate molecules, and the second one mainly due to the interaction between surfactant molecules at the adsorbent-solution interphase.

  9. Theory of interfacial phase transitions in surfactant systems

    Science.gov (United States)

    Shukla, K. P.; Payandeh, B.; Robert, M.

    1991-06-01

    The spin-1 Ising model, which is equivalent to the three-component lattice gas model, is used to study wetting transitions in three-component surfactant systems consisting of an oil, water, and a nonionic surfactant. Phase equilibria, interfacial profiles, and interfacial tensions for three-phase equilibrium are determined in mean field approximation, for a wide range of temperature and interaction parameters. Surfactant interaction parameters are found to strongly influence interfacial tensions, reducing them in some cases to ultralow values. Interfacial tensions are used to determine whether the middle phase, rich in surfactant, wets or does not wet the interface between the oil-rich and water-rich phases. By varying temperature and interaction parameters, a wetting transition is located and found to be of the first order. Comparison is made with recent experimental results on wetting transitions in ternary surfactant systems.

  10. Preparation of stable tea seed oil nano-particle emulsions by a low energy method with non-ionic surfactants

    Directory of Open Access Journals (Sweden)

    M. Kanlayavattanakul

    2017-06-01

    Full Text Available Tea seed oil nano-particle emulsions were prepared. Non-ionic surfactants containing Tween 80 and Span 80 (1:1, w/w were mixed with propanol (3-9:1, w/w to give Smix, which was thereafter mixed with tea seed oil. The mixture was titrated with water at 150 rpm to give clear or bluish and bluish-white emulsions. Twelve nano-particle emulsions with 64.64 to 72.73% Smix, 16.66 to 27.27% oil and 9.09 to 16.67% water with particle sizes between 207.00 to 430.10 nm, PDI of 0 to 0.4, ζ-potential of -42.00 to -49.63 mV, pH of 7.04 to 7.32 and 151.33 to 241.93 cps, were stable following an accelerated stability test and long term storage at room temperature and 4 and 45 ºC for 90 days, although one system (16.66% oil and 66.67% Smix was separated. This nano-particle emulsion formulation is concise and feasible for an industrial development of topical products containing tea seed oil.

  11. Simple one step synthesis of nonionic dithiol surfactants and their self-assembling with silver nanoparticles: Characterization, surface properties, biological activity

    Energy Technology Data Exchange (ETDEWEB)

    Abd-Elaal, Ali A., E-mail: ali_ashour5@yahoo.com; Tawfik, Salah M.; Shaban, Samy M.

    2015-07-01

    Graphical abstract: - Highlights: • Nonionic dithiol surfactants were synthesized by simple one step esterification. • The surface activity of the synthesized dithiol surfactants showed high tendency toward adsorption and micellization. • The nanostructure of the synthesized nonionic dithiol surfactants with silver nanoparticles was prepared. • The silver nanoparticles enhanced the biological activity of the synthesized dithiol surfactants. - Abstract: Simple esterification of 2-mercaptoacetic acid and polyethylene glycol with different molecular weights was done to form the desired nonionic dithiol surfactants. The chemical structures of synthesized thiol surfactants were confirmed using FT-IR and {sup 1}H NMR spectra. The surface activity of the synthesized surfactants was determined by measurement of the surface tension at different temperatures. The surface activity measurements showed their high tendency towards adsorption and micellization. The thermodynamic parameters of micellization (ΔG{sub mic}, ΔH{sub mic} and ΔS{sub mic}) and adsorption (ΔG{sub ads}, ΔG{sub ads} and ΔS{sub ads}) showed their tendency toward adsorption at the interfaces and also micellization in the bulk of their solutions. The nanostructure of the synthesized nonionic dithiol surfactants with silver nanoparticles was prepared and investigated using UV and TEM techniques. Screening tests of the synthesized dithiol surfactants and their nanostructure with silver nanoparticles, against gram positive bacteria (Bacillus subtilis and Microccus luteus), gram negative bacteria (Escherichia coli and Bordatella pertussis) and fungi (Aspergillus niger and Candida albicans) showed that they are highly active biocides. The presence of silver nanoparticles enhancement the biological activities of the individual synthesized nonionic dithiol surfactants.

  12. Impact of the degree of ethoxylation of the ethoxylated polysorbate nonionic surfactant on the surface self-assembly of hydrophobin-ethoxylated polysorbate surfactant mixtures.

    Science.gov (United States)

    Penfold, Jeffrey; Thomas, Robert K; Li, Peixun; Petkov, Jordan T; Tucker, Ian; Cox, Andrew R; Hedges, Nick; Webster, John R P; Skoda, Maximilian W A

    2014-08-19

    Neutron reflectivity measurements have been used to study the surface adsorption of the polyethylene sorbitan monostearate surfactant, with degrees of ethoxylation varying from 3 to 20 ethylene oxide groups, with the globular protein hydrophobin. The surface interaction between the ethoxylated polysorbate nonionic surfactants and the hydrophobin results in self-assembly at the air-solution interface in the form of a well-defined layered surface structure. The surface interaction arises from a combination of the hydrophobic interaction between the surfactant alkyl chain and the hydrophobic patch on the surface of the hydrophobin, and the hydrophilic interaction between the ethoxylated sorbitan headgroup and the hydrophilic regions on the surface of the hydrophobin. The results presented show that varying the degree of ethoxylation of the polysorbate surfactant changes the interaction between the surfactant and the hydrophobin and the packing, and hence the evolution in the resulting surface structure. The optimal degree of ethoxylation for multilayer formation is over a broad range, from of order 6 to 17 ethylene oxide groups, and for degrees of ethoxylation of 3 and 20 only monolayer adsorption of either the surfactant or the hydrophobin is observed.

  13. Adsorption of anionic and non-ionic surfactants on carbon nanotubes in water with dissipative particle dynamics simulation.

    Science.gov (United States)

    Vo, Minh D; Shiau, Benjamin; Harwell, Jeffrey H; Papavassiliou, Dimitrios V

    2016-05-28

    The morphology of surfactants physically adsorbed on the surface of carbon nanotubes (CNTs) has a significant impact on the dispersion of CNTs in the solution. The adsorption of the surfactants alfoterra 123-8s (AF) and tergitol 15-s-40 (TG) on CNTs was investigated with dissipative particle dynamics (DPD) simulations, as well as the behavior of the binary surfactant system with CNTs. Properties of surfactants (i.e., critical micelle concentration, aggregation number, shape and size of micelle, and diffusivity) in water were determined to validate the simulation model. Results indicated that the assembly of surfactants (AF and TG) on CNTs depends on the interaction of the surfactant tail and the CNT surface, where surfactants formed mainly hemimicellar structures. For surfactants in solution, most micelles had spherical shape. The particles formed by the CNT and the adsorbed surfactant became hydrophilic, due to the outward orientation of the head groups of the surfactants that formed monolayer adsorption. In the binary surfactant system, the presence of TG on the CNT surface provided a considerable hydrophilic steric effect, due to the EO groups of TG molecules. It was also seen that the adsorption of AF was more favorable than TG on the CNT surface. Diffusion coefficients for the surfactants in the bulk and surface diffusion on the CNT were calculated. These results are applicable, in a qualitative sense, to the more general case of adsorption of surfactants on the hydrophobic surface of cylindrically shaped nanoscale objects.

  14. Adsorption of anionic and non-ionic surfactants on carbon nanotubes in water with dissipative particle dynamics simulation

    Science.gov (United States)

    Vo, Minh D.; Shiau, Benjamin; Harwell, Jeffrey H.; Papavassiliou, Dimitrios V.

    2016-05-01

    The morphology of surfactants physically adsorbed on the surface of carbon nanotubes (CNTs) has a significant impact on the dispersion of CNTs in the solution. The adsorption of the surfactants alfoterra 123-8s (AF) and tergitol 15-s-40 (TG) on CNTs was investigated with dissipative particle dynamics (DPD) simulations, as well as the behavior of the binary surfactant system with CNTs. Properties of surfactants (i.e., critical micelle concentration, aggregation number, shape and size of micelle, and diffusivity) in water were determined to validate the simulation model. Results indicated that the assembly of surfactants (AF and TG) on CNTs depends on the interaction of the surfactant tail and the CNT surface, where surfactants formed mainly hemimicellar structures. For surfactants in solution, most micelles had spherical shape. The particles formed by the CNT and the adsorbed surfactant became hydrophilic, due to the outward orientation of the head groups of the surfactants that formed monolayer adsorption. In the binary surfactant system, the presence of TG on the CNT surface provided a considerable hydrophilic steric effect, due to the EO groups of TG molecules. It was also seen that the adsorption of AF was more favorable than TG on the CNT surface. Diffusion coefficients for the surfactants in the bulk and surface diffusion on the CNT were calculated. These results are applicable, in a qualitative sense, to the more general case of adsorption of surfactants on the hydrophobic surface of cylindrically shaped nanoscale objects.

  15. HPLC/ESI-quadrupole ion trap mass spectrometry for characterization and direct quantification of amphoteric and nonionic surfactants in aqueous samples

    Science.gov (United States)

    Levine, Lanfang H.; Garland, Jay L.; Johnson, Jodie V.

    2002-01-01

    An amphoteric (cocamidopropylbetaine, CAPB) and a nonionic (alcohol polyethoxylate, AE) surfactant were characterized by electrospray ionization quadrupole ion trap mass spectrometry (ESI-MS) as to their homologue distribution and ionization/fragmentation chemistry. Quantitative methods involving reversed-phase gradient HPLC and (+)ESI-MSn were developed to directly determine these surfactants in hydroponic plant growth medium that received simulated graywater. The predominant homologues, 12 C alkyl CAPB and 9 EO AE, were monitored to represent the total amount of the respective surfactants. The methods demonstrated dynamic linear ranges of 0.5-250 ng (r2 > 0.996) for CAPB and 8-560 ng (r2 > 0.998) for AE homologue mixture, corresponding to minimum quantification limits of 25 ppb CAPB and 0.4 ppm AE with 20-microL injections. This translated into an even lower limit for individual components due to the polydispersive nature of the surfactants. The procedure was successfully employed for the assessment of CAPB and AE biodegradation in a hydroponic plant growth system used as a graywater bioreactor.

  16. HPLC/ESI-quadrupole ion trap mass spectrometry for characterization and direct quantification of amphoteric and nonionic surfactants in aqueous samples

    Science.gov (United States)

    Levine, Lanfang H.; Garland, Jay L.; Johnson, Jodie V.

    2002-01-01

    An amphoteric (cocamidopropylbetaine, CAPB) and a nonionic (alcohol polyethoxylate, AE) surfactant were characterized by electrospray ionization quadrupole ion trap mass spectrometry (ESI-MS) as to their homologue distribution and ionization/fragmentation chemistry. Quantitative methods involving reversed-phase gradient HPLC and (+)ESI-MSn were developed to directly determine these surfactants in hydroponic plant growth medium that received simulated graywater. The predominant homologues, 12 C alkyl CAPB and 9 EO AE, were monitored to represent the total amount of the respective surfactants. The methods demonstrated dynamic linear ranges of 0.5-250 ng (r2 > 0.996) for CAPB and 8-560 ng (r2 > 0.998) for AE homologue mixture, corresponding to minimum quantification limits of 25 ppb CAPB and 0.4 ppm AE with 20-microL injections. This translated into an even lower limit for individual components due to the polydispersive nature of the surfactants. The procedure was successfully employed for the assessment of CAPB and AE biodegradation in a hydroponic plant growth system used as a graywater bioreactor.

  17. Gel Electrophoresis, Gel Chromatography and Sedimentation Analysis of Histones and Protamines in the Presence of Nonionic Surfactants

    OpenAIRE

    Hamana, Koei

    1982-01-01

    Histones and protamines behaved as a monomeric form in 0.9M acetic acid. When gel electrophoresis was carried out in 0.9M acetic acid, the mobilities of calf H2A, H2B, H3 and H4 histones were decreased proportionaly to the helix content of the histones but the mobilities of calf H1 histone and fish protamines were not decreased by the addition of 6mM nonionic surfactant into the gel. Degree of the decreasing on the mobilities of four histones was also proportional to the molecular weight of t...

  18. New hydrophilic interaction/reversed-phase mixed-mode stationary phase and its application for analysis of nonionic ethoxylated surfactants.

    Science.gov (United States)

    Liu, Xiaodong; Pohl, Christopher

    2008-05-16

    We have developed a new stationary phase that combines both hydrophilic interaction and reversed-phase characteristics. The new phase is based on high-purity, porous and spherical silica gel functionalized with a silyl ligand consisting of both hydrophilic and hydrophobic functionalities. This phase can be operated in both HILIC mode (high organic solvent) and RPLC mode (low organic solvent). An optimal balance of hydrophilic and hydrophobic moieties on the silica surface provides unique chromatographic properties that make it useful for determination of alkyl chain distribution and degree of ethoxylation (EO number) of nonionic ethoxylated surfactants.

  19. Sequential adsorption of an irreversibly adsorbed nonionic surfactant and an anionic surfactant at an oil/aqueous interface.

    Science.gov (United States)

    Kirby, Stephanie M; Anna, Shelley L; Walker, Lynn M

    2015-04-14

    Aerosol-OT (AOT) and Tween 80 are two of the main surfactants in commercial dispersants used in response to oil spills. Understanding how multicomponent surfactant systems interact at oil/aqueous interfaces is crucial for improving both dispersant design and application efficacy. This is true of many multicomponent formulations; a lack of understanding of competition for the oil/water interface hinders formulation optimization. In this study, we have characterized the sequential adsorption behavior of AOT on squalane/aqueous interfaces that have been precoated with Tween 80. A microtensiometer is used to measure the dynamic interfacial tension of the system. Tween 80 either partially or completely irreversibly adsorbs to squalane/aqueous interfaces when rinsed with deionized water. These Tween 80 coated interfaces are then exposed to AOT. AOT adsorption increases with AOT concentration for all Tween 80 coverages, and the resulting steady-state interfacial tension values are interpreted using a Langmuir isotherm model. In the presence of 0.5 M NaCl, AOT adsorption significantly increases due to counterion charge screening of the negatively charged head groups. The presence of Tween 80 on the interface inhibits AOT adsorption, reducing the maximum surface coverage as compared to a clean interface. Tween 80 persists on the interface even after exposure to high concentrations of AOT.

  20. Influence of a nonionic surfactant (Triton X-100) on contaminant distribution between water and several soil solids

    Science.gov (United States)

    Lee, J.-F.; Liao, P.-M.; Kuo, C.-C.; Yang, H.-T.; Chiou, C.T.

    2000-01-01

    The influence of a nonionic surfactant (Triton X-100) on the contaminant distribution coefficients in solid-water mixtures was determined for a number of relatively nonpolar compounds (contaminants) on several natural solids. The studied compounds consisted of BTEX (benzene, toluene, ethylbenzene, and p-xylene) and chlorinated pesticides (lindane, ??-BHC, and heptachlor epoxide), which span several orders of magnitude in water solubility (S(W)); the solid samples comprised a bentonite, a peat, and two other soils, which cover a wide range of solid organic matter (SOM) content. The applied surfactant concentrations (X) ranged from below the (nominal) CMC to 2-3 times the CMC. For relatively water-soluble BTEX compounds, the distribution coefficients with surfactant (K*(d)) all exceeded those without surfactant (K(d)); the K*(d)/K(d) ratios increased with increasing S(w) from p-xylene to benzene on each solid at a given X, with increasing X for each compound on a solid, and with decreasing solid SOM content for each compound over the range of X studied. For the less-soluble pesticides, the K*(d)/K(d) ratios exhibited a large increase with X for bentonite, a marginal change (increase or decrease) for a soil of 2.4% SOM, and a moderate-to-large decrease for two soils of 14.8% and 86.4% SOM. These unique observations were rationalized in terms of the properties of the compound, the amount of surfactant sorbed on the solid, the enhanced solubilization of the compound by surfactant in water, and the relative effects of the surfactant when adsorbed on minerals and when partitioned into SOM. (C) 2000 Academic Press.

  1. Nonionic surfactants with linear and branched hydrocarbon tails: compositional analysis, phase behavior, and film properties in bicontinuous microemulsions.

    Science.gov (United States)

    Frank, Christian; Frielinghaus, Henrich; Allgaier, Jürgen; Prast, Hartmut

    2007-06-05

    Nonionic alcohol ethoxylates are widely used as surfactants in many different applications. They are available in a large number of structural varieties as technical grade products. This variety is mainly based on the use of different alcohols, which can be linear or branched and contain primary, secondary, or tertiary OH groups. Technical grade products are poorly defined as they are composed of alcohol mixtures being different in chain length and structure. On the other hand, monodisperse alcohol ethoxylates are commercially available; however, these surfactants exist only with primary and linear alcohols. In the field of microemulsion research the monodisperse alcohol ethoxylates are widely used. The phase behavior and film properties of these surfactants were studied intensively with respect to the size of the hydrophilic and hydrophobic moieties. Due to the lack of appropriate model surfactants until now, there is little information on how the structure of the hydrocarbon tail influences the microemulsion behavior. To examine structural influences, we synthesized a series of surfactants with the composition C10E5 and having different linear and branched hydrocarbon tails. The surfactants were monodisperse with respect to the hydrocarbon tail but polydisperse with respect to the ethoxylation degree. However, a detailed characterization showed that they were similar concerning the average ethoxylation degree and EO chain length distribution. The phase behavior was investigated for bicontinuous microemulsions, and the film properties were analyzed by small-angle neutron scattering (SANS). Our results show that the structure of the hydrocarbon tail strongly influences the microemulsion behavior. The most efficient surfactant is obtained if the hydrocarbon tail is linear and the hydrophilic group is attached in the C-1 position. Surfactants having the hydrophilic group bound to the C-2 or C-4 position or which contain a branched hydrocarbon tail are less efficient

  2. Aggregation and electrochemical properties of 1-(4-chlorophenyl)-3-dodecanoylthiourea: A novel thiourea-based non-ionic surfactant

    Indian Academy of Sciences (India)

    Imdad Ullah; Afzal Shah; Musharaf Khan; Khalida Akhter; Amin Badshah

    2015-08-01

    A novel thiourea-based non-ionic surfactant 1-(4-chlorophenyl)-3-dodecanoylthiourea (4CPDT) was synthesized from decanoyl chloride, potassium thiocyanate and 4-chloroanline in high yield. The structural chemistry of the compound was done by multiple nuclear NMR (1H, 13 C) and FT-IR. UV-Visible spectrophotometry and pendant drop methods were used to evaluate their critical micelle concentration in ethanol and hexane. This surfactant showed very low solubility in water, and interestingly low but well-defined, sub-millimolar critical micelle concentration (CMC) in ethanol and hexane, demonstrating that this is moderately amphiphobic. Its low value of critical micelle concentration indicates economical use for cleaning purposes and environment-friendly applications. It was also characterized by cyclic and square wave voltammetry and found to be electrochemically active giving sharp signal in different pH media.

  3. Enhancement of intestinal absorption of poorly absorbed hydrophilic compounds by simultaneous use of mucolytic agent and non-ionic surfactant.

    Science.gov (United States)

    Takatsuka, Shinya; Kitazawa, Takeo; Morita, Takahiro; Horikiri, Yuji; Yoshino, Hiroyuki

    2006-01-01

    The effect of co-administration of a mucolytic agent with a penetration enhancer was assessed on the intestinal absorption of poorly absorbed hydrophilic compounds. Fluorescein isothiocyanate-labeled dextran with average molecular weight of ca. 4.4 kDa (FD-4) was used as a model compound, and N-acetylcysteine (NAC) was used as a mucolytic agent. Sodium caprate (C10), tartaric acid (TA), sodium taurodeoxycholate (TDC), sodium dodecyl sulfate (SDS), p-t-octyl phenol polyoxyethylene-9.5 (Triton X-100, TX-100) were selected as penetration enhancers with different mechanisms of action. Various dosing solutions containing a penetration enhancer in the absence or in the presence of NAC were directly administered into the exposed rat jejunum, and the bioavailability of FD-4 up to 2 h was determined. The extent of improvement by co-administration was highly dependent on the penetration enhancer species applied. The observed enhancement was thought to result from the mucolytic activity of NAC, which can reduce the mucus viscosity and facilitate the penetration of FD-4 to mucosal membrane. Among the combinations tested, the simultaneous administration of NAC and TX-100 provided the highest enhancement (22.5-fold) of intestinal FD-4 absorption compared to the control. Although the detailed mechanism for the observed drastic improvement is unclear, one possible reason was thought to be due to the improved diffusivity of TX-100 micellar system in the mucus layer. All these results suggest that the combination of a mucolytic agent and a non-ionic surfactant may have potential as an enhancing system for peroral delivery of poorly absorbed hydrophilic compounds like protein and peptide drugs.

  4. Effective Surfactants Blend Concentration Determination for O/W Emulsion Stabilization by Two Nonionic Surfactants by Simple Linear Regression

    National Research Council Canada - National Science Library

    Hassan, A K

    2015-01-01

    ...°. Applying the simple linear regression least squares method statistical analysis to the temperature-conductivity obtained data determines the effective surfactants blend concentration required...

  5. Cationic vesicles based on non-ionic surfactant and synthetic aminolipids mediate delivery of antisense oligonucleotides into mammalian cells.

    Science.gov (United States)

    Grijalvo, Santiago; Alagia, Adele; Puras, Gustavo; Zárate, Jon; Pedraz, Jose Luis; Eritja, Ramon

    2014-07-01

    A formulation based on a synthetic aminolipid containing a double-tailed with two saturated alkyl chains along with a non-ionic surfactant polysorbate-80 has been used to form lipoplexes with an antisense oligonucleotide capable of inhibiting the expression of Renilla luciferase mRNA. The resultant lipoplexes were characterized in terms of morphology, Zeta potential, average size, stability and electrophoretic shift assay. The lipoplexes did not show any cytotoxicity in cell culture up to 150 mM concentration. The gene inhibition studies demonstrated that synthetic cationic vesicles based on non-ionic surfactant and the appropriate aminolipid play an important role in enhancing cellular uptake of antisense oligonucleotides obtaining promising results and efficiencies comparable to commercially available cationic lipids in cultured mammalian cells. Based on these results, this amino lipid moiety could be considered as starting point for the synthesis of novel cationic lipids to obtain potential non-viral carriers for antisense and RNA interference therapies. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Synergetic effect of chelating agent and nonionic surfactant for benzotriazole removal on post Cu-CMP cleaning

    Science.gov (United States)

    Yanlei, Li; Yuling, Liu; Chenwei, Wang; Yue, Li

    2016-08-01

    The cleaning of copper interconnects after chemical mechanical planarization (CMP) process is a critical step in integrated circuits (ICs) fabrication. Benzotriazole (BTA), which is used as corrosion inhibitor in the copper CMP slurry, is the primary source for the formation of organic contaminants. The presence of BTA can degrade the electrical properties and reliability of ICs which needs to be removed by using an effective cleaning solution. In this paper, an alkaline cleaning solution was proposed. The alkaline cleaning solution studied in this work consists of a chelating agent and a nonionic surfactant. The removal of BTA was characterized by contact angle measurements and potentiodynamic polarization studies. The cleaning properties of the proposed cleaning solution on a 300 mm copper patterned wafer were also quantified, total defect counts after cleaning was studied, scanning electron microscopy (SEM) review was used to identify types of BTA to confirm the ability of cleaning solution for BTA removal. All the results reveal that the chelating agent can effectively remove the BTA residual, nonionic surfactant can further improve the performance. Project supported by the Natural Science Foundation of Hebei Province, China (No. F2015202267) and the Scientific Innovation Grant for Excellent Young Scientists of Hebei University of Technology (No. 2015007).

  7. Photochromic hybrid organic-inorganic liquid-crystalline materials built from nonionic surfactants and polyoxometalates: elaboration and structural study.

    Science.gov (United States)

    Poulos, Andreas S; Constantin, Doru; Davidson, Patrick; Impéror, Marianne; Pansu, Brigitte; Panine, Pierre; Nicole, Lionel; Sanchez, Clément

    2008-06-17

    This work reports the elaboration and structural study of new hybrid organic-inorganic materials constructed via the coupling of liquid-crystalline nonionic surfactants and polyoxometalates (POMs). X-ray scattering and polarized light microscopy demonstrate that these hybrid materials, highly loaded with POMs (up to 18 wt %), are nanocomposites of liquid-crystalline lamellar structure (Lalpha), with viscoelastic properties close to those of gels. The interpretation of X-ray scattering data strongly suggests that the POMs are located close to the terminal -OH groups of the nonionic surfactants, within the aqueous sublayers. Moreover, these materials exhibit a reversible photochromism associated to the photoreduction of the polyanion. The photoinduced mixed-valence behavior has been characterized through ESR and UV-visible-near-IR spectroscopies that demonstrate the presence of W(V) metal cations and of the characteristic intervalence charge transfer band in the near-IR region, respectively. These hybrid nanocomposites exhibit optical properties that may be useful for applications involving UV-light-sensitive coatings or liquid-crystal-based photochromic switches. From a more fundamental point of view, these hybrid materials should be very helpful models for the study of both the static and dynamic properties of nano-objects confined within soft lamellar structures.

  8. IgG1 adsorption to siliconized glass vials-influence of pH, ionic strength, and nonionic surfactants.

    Science.gov (United States)

    Höger, Kerstin; Mathes, Johannes; Frieß, Wolfgang

    2015-01-01

    In this study, the adsorption of an IgG1 antibody to siliconized vials was investigated with focus on the formulation parameters pH, ionic strength, and nonionic surfactants. Electrophoretic mobility measurements were performed to investigate the charge characteristics of protein and siliconized glass particles at different pH values. Calculation of the electrokinetic charge density allowed further insight into the energetic conditions in the protein-sorbent interface. Maximum adsorption of IgG1 was found at acidic pH values and could be correlated with energetically favorable minimal ion incorporation into the interface. The importance of electrostatic interactions for IgG1 adsorption at acidic pH values was also confirmed by the efficient adsorption reduction at decreased solution ionic strength. A second adsorption maximum around the pI of the protein was assigned to hydrophobic interactions with the siliconized surface. Addition of the nonionic surfactants poloxamer 188 or polysorbate 80 resulted in almost complete suppression of adsorption at pH 7.2, and a strong but less efficient effect at pH 4 on siliconized glass vials. This adsorption suppression was much less pronounced on borosilicate glass vials. From these results, it can be concluded that electrostatic interactions contribute substantially to IgG1 adsorption to siliconized glass vials especially at acidic formulation pH.

  9. A combined binding mechanism of nonionic ethoxylated surfactants to bovine serum albumin revealed by fluorescence and circular dichroism.

    Science.gov (United States)

    Iovescu, Alina; Băran, Adriana; Stîngă, Gabriela; Cantemir-Leontieş, Anca Ruxandra; Maxim, Monica Elisabeta; Anghel, Dan Florin

    2015-12-01

    The study systematically investigates aqueous mixtures of fixed bovine serum albumin (BSA) and various ethoxylated nonionic surfactants belonging to a homologous series or not. Mono-disperse tetra-(C12E4), hexa-(C12E6) and octa-ethyleneglycol mono-n-dodecyl ether (C12E8), and poly-disperse eicosa-ethyleneglycol mono-n-tetradecyl ether (C14EO20) are respectively employed. Fluorescence and circular dichroism measurements are performed at surfactant/protein molar ratios (rm)s lower and higher than one. We aim to get new insights into the binding mechanism of these species and to differentiate among the interaction abilities of these surfactants. The relative magnitude of the binding thermodynamic parameters by fluorescence, and the increase of α-helix prove that hydrogen bonding drives the interaction next to the hydrophobic attraction. C12En (n=4,6,8) develop more H bonds with the albumin than C14EO20 owing to a zigzag conformation of their short ethyleneoxide chains. Among the homologous surfactants, C12E6 has a slightly stronger interaction with BSA due to a maximal number of H bonds at a minimal hindering. Static fluorescence and dynamic fluorescence indicate an inter-conversion between the tryptophan (Trp) rotamers which happens around the surfactants critical micellar concentration. For C14EO20, the meander conformation of the polar group determines a less evident conversion of the Trp rotamers and smaller α-helix rise. Binding isotherms of the homologous surfactants and the fluorescence quenching mechanism by C12E6 are also provided.

  10. Acute toxicity of anionic and non-ionic surfactants to aquatic organisms.

    Science.gov (United States)

    Lechuga, M; Fernández-Serrano, M; Jurado, E; Núñez-Olea, J; Ríos, F

    2016-03-01

    The environmental risk of surfactants requires toxicity measurements. As different test organisms have different sensitivity to the toxics, it is necessary to establish the most appropriate organism to classify the surfactant as very toxic, toxic, harmful or safe, in order to establish the maximum permissible concentrations in aquatic ecosystems. We have determined the toxicity values of various anionic surfactants ether carboxylic derivatives using four test organisms: the freshwater crustacean Daphnia magna, the luminescent bacterium Vibrio fischeri, the microalgae Selenastrum capricornutum (freshwater algae) and Phaeodactylum tricornutum (seawater algae). In addition, in order to compare and classify the different families of surfactants, we have included a compilation of toxicity data of surfactants collected from literature. The results indicated that V. fischeri was more sensitive to the toxic effects of the surfactants than was D. magna or the microalgae, which was the least sensitive. This result shows that the most suitable toxicity assay for surfactants may be the one using V. fischeri. The toxicity data revealed considerable variation in toxicity responses with the structure of the surfactants regardless of the species tested. The toxicity data have been related to the structure of the surfactants, giving a mathematical relationship that helps to predict the toxic potential of a surfactant from its structure. Model-predicted toxicity agreed well with toxicity values reported in the literature for several surfactants previously studied. Predictive models of toxicity is a handy tool for providing a risk assessment that can be useful to establish the toxicity range for each surfactant and the different test organisms in order to select efficient surfactants with a lower impact on the aquatic environment.

  11. Simple one step synthesis of nonionic dithiol surfactants and their self-assembling with silver nanoparticles: Characterization, surface properties, biological activity

    Science.gov (United States)

    Abd-Elaal, Ali A.; Tawfik, Salah M.; Shaban, Samy M.

    2015-07-01

    Simple esterification of 2-mercaptoacetic acid and polyethylene glycol with different molecular weights was done to form the desired nonionic dithiol surfactants. The chemical structures of synthesized thiol surfactants were confirmed using FT-IR and 1H NMR spectra. The surface activity of the synthesized surfactants was determined by measurement of the surface tension at different temperatures. The surface activity measurements showed their high tendency towards adsorption and micellization. The thermodynamic parameters of micellization (ΔGmic, ΔHmic and ΔSmic) and adsorption (ΔGads, ΔGads and ΔSads) showed their tendency toward adsorption at the interfaces and also micellization in the bulk of their solutions. The nanostructure of the synthesized nonionic dithiol surfactants with silver nanoparticles was prepared and investigated using UV and TEM techniques. Screening tests of the synthesized dithiol surfactants and their nanostructure with silver nanoparticles, against gram positive bacteria (Bacillus subtilis and Microccus luteus), gram negative bacteria (Escherichia coli and Bordatella pertussis) and fungi (Aspergillus niger and Candida albicans) showed that they are highly active biocides. The presence of silver nanoparticles enhancement the biological activities of the individual synthesized nonionic dithiol surfactants.

  12. STUDY ON A NEW NONIONIC MICRIOPARTICLE RETENTION SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Xiuwu Hou; Xiaofan Zhou; Rui Peng; Fei Wang

    2004-01-01

    The retention and drainage performances of microparticle retention system were studied in this paper, through measuring the improvement of beaten degree and retention ratio of slurry. The effects the retention system on paper sheet were discussed by measuring physical properties of paper. Compared with the influence of Hydrocol system (CPAM/bentonite) on the aspects of retention aid and drainage properties as well as increased product cost per ton paper, the developed nonionic system has some superiority and better practicability.

  13. Occurrence, distribution and partitioning of nonionic surfactants and pharmaceuticals in the urbanized Long Island Sound Estuary (NY).

    Science.gov (United States)

    Lara-Martín, Pablo A; González-Mazo, Eduardo; Petrovic, Mira; Barceló, Damià; Brownawell, Bruce J

    2014-08-30

    This work deals with the environmental distribution of nonionic surfactants (nonylphenol and alcohol ethoxylates), their metabolites (NP, nonylphenol; NPEC, nonylphenol ethoxycarboxylates; and PEG, polyethylene glycols) and a selection of 64 pharmaceuticals in the Long Island Sound (LIS) Estuary which receives important sewage discharges from New York City (NYC). Most target compounds were efficiently removed (>95%) in one wastewater treatment plant monitored, with the exception of NPEC and some specific drugs (e.g., hydrochlorothiazide). Concentrations of surfactants (1.4-4.5 μg L(-1)) and pharmaceuticals (0.1-0.3 μg L(-1)) in seawater were influenced by tides and sampling depth, consistent with salinity differences. Surfactants levels in suspended solids samples were higher than 1 μg g(-1), whereas only most hydrophobic or positively charged pharmaceuticals could be found (e.g., tamoxifen, clarithromycin). Maximum levels of target compounds in LIS sediments (PEG at highest concentrations, 2.8 μg g(-1)) were measured nearest NYC, sharply decreasing with distance from major sewage inputs.

  14. Synthesis of nonionic reduced-sugar based bola amphiphiles and gemini surfactants with an alpha,omega-diamino-(oxa)alkyl spacer

    NARCIS (Netherlands)

    Wagenaar, Anno; Engberts, Jan B. F. N.

    2007-01-01

    Reduced-sugar based gemini surfactants with an alpha,omega-diamino-(oxa) alkyl spacer exhibit a rich pH-dependent aggregation behavior and are efficient DNA carriers in gene transfection. Herein, we describe an improved synthetic procedure for these amphiphiles. First, a series of novel nonionic

  15. Thermodynamics of micellization of nonionic saccharide-based N-acyl-N-alkylaldosylamine and N-acyl-N-alkylamino-1-deoxyalditol surfactants

    NARCIS (Netherlands)

    Pestman, J.M.; Kevelam, J.; Blandamer, M.J.; Doren, H.A. van; Kellogg, R.M.; Engberts, J.B.F.N.

    1999-01-01

    Eight homologous series of nonionic carbohydrate-derived surfactants in which the alkyl chains are linked through N-acylated amine bonds were synthesized, and their critical micelle concentrations (cmc's) and standard enthalpies of micellization were determined using titration microcalorimetry. Gibb

  16. Synthesis of nonionic reduced-sugar based bola amphiphiles and gemini surfactants with an alpha,omega-diamino-(oxa)alkyl spacer

    NARCIS (Netherlands)

    Wagenaar, Anno; Engberts, Jan B. F. N.

    2007-01-01

    Reduced-sugar based gemini surfactants with an alpha,omega-diamino-(oxa) alkyl spacer exhibit a rich pH-dependent aggregation behavior and are efficient DNA carriers in gene transfection. Herein, we describe an improved synthetic procedure for these amphiphiles. First, a series of novel nonionic bol

  17. DIRECT ETHOXYLATION OF GLYCEROL MONO OLEATE FROM PALM OIL DERIVATE AS A NOVEL NON-IONIC POLYMERIC SURFACTANT

    Directory of Open Access Journals (Sweden)

    Joddy Arya Laksmono

    2012-01-01

    Full Text Available The work investigates ethoxylation of glycerol mono oleate (GMO performed in the presence of an alkaline catalyst. Glycerol mono oleate applied was derivated from Indonesian palm oil. The reaction was conducted with variation of Glycerol mono oleate : ethylene oxide ratio, temperature, and catalyst concentration. Forier Transform Infra Red (FTIR and Nuclear Magnetic Resonance (NMR analysis showed products with degrees of ethoxylation n=2 and n=3. FTIR analysis of products gave a new peak at 1570 cm-1 supporting that C-O-C bond was formed. New peaks were also observed in 13-C-NMR analysis of run 2 and run 3 with chemical shift of (δ 61.3385; 61.9108; 62.5117; 63.8566; 66.0982; 72.6127 and 61.2172; 63.2393; 65.9100; 72.5201, respectively. Glycerol mono oleate ethoxylated was yielded and could be useful for a novel non-ionic polymeric surfactant.

  18. Nonionic surfactant organoclay obtaining from Pedra Lavrada District, PB, Brazil; Organofilizacao de uma argila esmectitica no municipio de Pedra Lavrada, PB, atraves de tensoativo nao ionico

    Energy Technology Data Exchange (ETDEWEB)

    Silva, I.A. da; Cardoso, M.A.F.; Figueiredo, J.M.R.; Silva, C.D.; Neves, G.A.; Ferreira, H. C., E-mail: isabelle_albuquerquecg@hotmail.com [Universidade Federal de Campina Grande (UAEMa/CCT/UFCG), PB (Brazil). Unidade Academinca de Engenharia de Materiais; Ferreira, H.S. [Universidade Federal da Paraiba (DEMAT/CT/UFPB), Joao Pessoa, PB (Brazil)

    2012-07-01

    The oil industry has invested for many years in the use of smectite clay as a dispersing agent in the composition of drilling fluids for oil wells water based and oil based. The State of Paraiba is one of the largest producers of clays and recently discovered new deposits in the regions of Cubati and Pedra Lavrada by creating a great expectation of the expansion of mineral production in the region. The aim of this work is a smectite clays organophilization of the city of Pedra Lavrada, with the addition of nonionic surfactant. After organophilization clay was characterized by X-ray diffraction and Foster swelling in order to choose the most suitable surfactant through the organic liquid dispersant diesel. The results showed that incorporation of surfactant used in the clay interlayer spacing increased significantly, and that the dispersions showed rheological properties within the specifications of PETROBRAS, for use of organophilic clays in drilling fluids in nonionic base. (author)

  19. Self-nanoemulsifying performance of two grades of Lauroglycol (Lauroglycol-90 and Lauroglycol-FCC) in the presence of mixed nonionic surfactants.

    Science.gov (United States)

    Shakeel, Faiyaz; Haq, Nazrul; Alanazi, Fars K; Alsarra, Ibrahim A

    2014-11-01

    The present study was undertaken to evaluate the impact of various combinations of nonionic surfactants on self-nanoemulsifying performance of two grades of Lauroglycol (Lauroglycol-90 and Lauroglycol-FCC) in glibenclamide (GBN) nanoemulsion. Formulations (L1-L30) were prepared by spontaneous emulsification method. Prepared formulations were subjected to thermodynamic stability and self-nanoemulsification test. Results of thermodynamic stability and self-nanoemulsification tests were confirmed by further characterization of these formulations in terms of droplet size, viscosity, refractive index and % transmittance. Formulations prepared with Labrasol, HCO-60 and Gelucire-44/14 were found to be suitable for self-emulsifying drug delivery system only whereas those prepared with Tween-80 and Cremophor-EL were found to be suitable for self-nanoemulsifying or self-microemulsifying drug delivery system of GBN with respect to Lauroglycol-90 or Lauroglycol-FCC. Formulation L24 (Lauroglycol-FCC/Tween-80/ethanol/water) was optimized as best formulation for self-nanoemulsifying drug delivery system of GBN. These results indicated that Tween-80 could be the best surfactant in terms of self-nanoemulsification.

  20. Nonionic metal-chelating surfactants mediated solvent-free thermo-induced separation of uranyl

    Energy Technology Data Exchange (ETDEWEB)

    Larpent, Ch.; Prevost, S. [Versailles-St-Quentin Univ., Institut Lavoisier, UMR-CNRS 8180, 78 - Versailles (France); Prevost, S.; Zemb, Th.; Testard, F. [CEA Saclay, Dept. de Recherche sur l' Etat Condense, les Atomes et les Molecules (DSM/DRECAM/SCM/LIONS), 91 - Gif sur Yvette (France); Berthon, L. [CEA Valrho, Site de Marcoule, Dept. Radiochimie et Procedes (DEN/DRCP/SCPS/LCSE), 30 (France)

    2007-08-15

    Thermo-responsive metal-chelating surfactants permit the solvent-free, cloud point extraction of uranyl nitrate and afford a real molecular economy compared to conventional separation techniques. (authors)

  1. Improvements in permeation and fouling resistance of PVC ultrafiltration membranes via addition of Tetronic-1107 and Triton X-100 as two non-ionic and hydrophilic surfactants.

    Science.gov (United States)

    Rabiee, Hesamoddin; Seyedi, S Mojtaba; Rabiei, Hossein; Alvandifar, Negar

    2016-09-01

    Two non-ionic and hydrophilic surfactant additives, Tetronic-1107 and Triton X-100, were added to poly(vinyl chloride)/NMP polymeric solution to prepare ultrafiltration membranes via immersion precipitation. Surfactants at three different weight percentages up to 6 wt% were added, and the fabricated membranes were characterized and their performance for water treatment in the presence of bovine serum albumin (BSA) as a foulant was assessed. The scanning electron microscopy images indicated remarkable changes in morphology due to higher thermodynamic instability after surfactant addition. The membranes are more porous with more macro-voids in the sub-layer. Plus, the membranes become more hydrophilic. Water flux increases for the modified membranes by nearly two times and the ability of membranes for flux recovery increases from 66% to over 83%. BSA rejection reduces slightly with the addition of surfactants, however this parameter is still almost over 90% for the membranes with the highest amount of surfactants.

  2. Non-ionic surfactant modified ligand exchange chromatography using copper (II) complex of N,N-dimethyl-L-phenylalanine as the chiral additive for enantioselective amino acids separation

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrova, Pepa [TU Kaiserslautern, Institut fuer Thermische Verfahrenstechnik, P.O. Box 3049, Gottlieb-Daimler-Str. 44, 67653 Kaiserslautern (Germany); Bart, Hans-Joerg, E-mail: bart@mv.uni-kl.de [TU Kaiserslautern, Institut fuer Thermische Verfahrenstechnik, P.O. Box 3049, Gottlieb-Daimler-Str. 44, 67653 Kaiserslautern (Germany)

    2010-03-17

    The influence of non-ionic surfactants on the selectivity and retention in the ligand exchange chromatography for the enantioselective separation of racemic mixtures of the amino acids DL-methionine, DL-leucine, DL-valine and DL-tyrosine applying chiral mobile phases was investigated, whereas five different surfactants were tested as modifiers. The experiments were carried out using a commercially available non-chiral RP-C8 column and the copper (II) complex of N,N-dimethyl-L-phenylalanine as the chiral additive. Varying the surfactant concentrations the retention factors and the selectivity could be controlled and in general no negative influence on the separation (due to surfactant adsorption on the non-chiral stationary phase) occurred. Changing the temperature the van't Hoff plots were obtained and the thermodynamic parameters calculated. Temperature had influence on the selectivity for each surfactant and lowered the retention times as expected.

  3. Non-ionic surfactant modified ligand exchange chromatography using copper (II) complex of N,N-dimethyl-L-phenylalanine as the chiral additive for enantioselective amino acids separation.

    Science.gov (United States)

    Dimitrova, Pepa; Bart, Hans-Jörg

    2010-03-17

    The influence of non-ionic surfactants on the selectivity and retention in the ligand exchange chromatography for the enantioselective separation of racemic mixtures of the amino acids dl-methionine, dl-leucine, dl-valine and dl-tyrosine applying chiral mobile phases was investigated, whereas five different surfactants were tested as modifiers. The experiments were carried out using a commercially available non-chiral RP-C8 column and the copper (II) complex of N,N-dimethyl-l-phenylalanine as the chiral additive. Varying the surfactant concentrations the retention factors and the selectivity could be controlled and in general no negative influence on the separation (due to surfactant adsorption on the non-chiral stationary phase) occurred. Changing the temperature the van't Hoff plots were obtained and the thermodynamic parameters calculated. Temperature had influence on the selectivity for each surfactant and lowered the retention times as expected.

  4. Cloud Point Extraction of Parabens Using Non-Ionic Surfactant with Cylodextrin Functionalized Ionic Liquid as a Modifier

    Science.gov (United States)

    Noorashikin, Md Saleh; Raoov, Muggundha; Mohamad, Sharifah; Abas, Mhd Radzi

    2013-01-01

    A cloud point extraction (CPE) process using non-ionic surfactant (DC193C) to extract selected paraben compounds from water samples was investigated using reversed phase high performance liquid chromatography (RP-HPLC). The CPE process with the presence of β-cyclodextrin (βCD) functionalized ionic liquid as a modifier (CPE-DC193C-βCD-IL) is a new extraction technique that has been applied on the optimization of parameters, i.e., pH, βCD-IL concentration and phase volume ratio. This CPE-DC193C-βCD-IL method is facilitated at 30 °C, showing great losses of water content in the surfactant-rich phase, resulting in a high pre-concentration factor and high distribution coefficient. The developed method CPE-DC193C-βCD-IL did show enhanced properties compared to the CPE method without the modifier (CPE-DC193C). The developed method of CPE-DC193C-βCD-IL gives an excellent performance on the detection of parabens from water samples with the limit of detection falling in the range of 0.013–0.038 μg mL−1. Finally, the inclusion complex formation, hydrogen bonding, and π–π interaction between the βCD-IL, benzyl paraben (ArP), and DC 193C were proven using 1H NMR and 2D NOESY spectroscopy. PMID:24351832

  5. Cloud Point Extraction of Parabens Using Non-Ionic Surfactant with Cylodextrin Functionalized Ionic Liquid as a Modifier

    Directory of Open Access Journals (Sweden)

    Md Saleh Noorashikin

    2013-12-01

    Full Text Available A cloud point extraction (CPE process using non-ionic surfactant (DC193C to extract selected paraben compounds from water samples was investigated using reversed phase high performance liquid chromatography (RP-HPLC. The CPE process with the presence of β-cyclodextrin (βCD functionalized ionic liquid as a modifier (CPE-DC193C-βCD-IL is a new extraction technique that has been applied on the optimization of parameters, i.e., pH, βCD-IL concentration and phase volume ratio. This CPE-DC193C-βCD-IL method is facilitated at 30 °C, showing great losses of water content in the surfactant-rich phase, resulting in a high pre-concentration factor and high distribution coefficient. The developed method CPE-DC193C-βCD-IL did show enhanced properties compared to the CPE method without the modifier (CPE-DC193C. The developed method of CPE-DC193C-βCD-IL gives an excellent performance on the detection of parabens from water samples with the limit of detection falling in the range of 0.013–0.038 µg mL−1. Finally, the inclusion complex formation, hydrogen bonding, and π–π interaction between the βCD-IL, benzyl paraben (ArP, and DC 193C were proven using 1H NMR and 2D NOESY spectroscopy.

  6. Cloud point extraction of vanadium in pharmaceutical formulations, dialysate and parenteral solutions using 8-hydroxyquinoline and nonionic surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Sumaira, E-mail: skhanzai@gmail.com [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Kazi, Tasneem G., E-mail: tgkazi@yahoo.com [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Baig, Jameel A., E-mail: jab_mughal@yahoo.com [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Young Welfare Society Mughalabad, Near Akri, Taluka Faiz Ganj, District Khairpur Sindh (Pakistan); Kolachi, Nida F., E-mail: nidafatima6@gmail.com [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Afridi, Hassan I., E-mail: hassanimranafridi@yahoo.com [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Wadhwa, Sham Kumar [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Shah, Abdul Q., E-mail: aqshah07@yahoo.com [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Kandhro, Ghulam A. [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan); Shah, Faheem, E-mail: shah_ceac@yahoo.com [Center of Excellence in Analytical Chemistry, University of Sindh, Jamshoro 76080 (Pakistan)

    2010-10-15

    A cloud point extraction (CPE) method has been developed for the determination of trace quantity of vanadium ions in pharmaceutical formulations (PF), dialysate (DS) and parenteral solutions (PS). The CPE of vanadium (V) using 8-hydroxyquinoline (oxine) as complexing reagent and mediated by nonionic surfactant (Triton X-114) was investigated. The parameters that affect the extraction efficiency of CPE, such as pH of sample solution, concentration of oxine and Triton X-114, equilibration temperature and time period for shaking were investigated in detail. The validity of CPE of V was checked by standard addition method in real samples. The extracted surfactant-rich phase was diluted with nitric acid in ethanol, prior to subjecting electrothermal atomic absorption spectrometry. Under these conditions, the preconcentration of 50 mL sample solutions, allowed raising an enrichment factor of 125-fold. The lower limit of detection obtained under the optimal conditions was 42 ng/L. The proposed method has been successfully applied to the determination of trace quantity of V in various pharmaceutical preparations with satisfactory results. The concentration ranges of V in PF, DS and PS samples were found in the range of 10.5-15.2, 0.65-1.32 and 1.76-6.93 {mu}g/L, respectively.

  7. Cloud point extraction of parabens using non-ionic surfactant with cylodextrin functionalized ionic liquid as a modifier.

    Science.gov (United States)

    Noorashikin, Md Saleh; Raoov, Muggundha; Mohamad, Sharifah; Abas, Mhd Radzi

    2013-12-17

    A cloud point extraction (CPE) process using non-ionic surfactant (DC193C) to extract selected paraben compounds from water samples was investigated using reversed phase high performance liquid chromatography (RP-HPLC). The CPE process with the presence of β-cyclodextrin (βCD) functionalized ionic liquid as a modifier (CPE-DC193C-βCD-IL) is a new extraction technique that has been applied on the optimization of parameters, i.e., pH, βCD-IL concentration and phase volume ratio. This CPE-DC193C-βCD-IL method is facilitated at 30 °C, showing great losses of water content in the surfactant-rich phase, resulting in a high pre-concentration factor and high distribution coefficient. The developed method CPE-DC193C-βCD-IL did show enhanced properties compared to the CPE method without the modifier (CPE-DC193C). The developed method of CPE-DC193C-βCD-IL gives an excellent performance on the detection of parabens from water samples with the limit of detection falling in the range of 0.013-0.038 µg mL-1. Finally, the inclusion complex formation, hydrogen bonding, and π-π interaction between the βCD-IL, benzyl paraben (ArP), and DC 193C were proven using 1H NMR and 2D NOESY spectroscopy.

  8. Synthesis of composite particles through emulsion polymerization based on silica/fluoroacrylate-siloxane using anionic reactive and nonionic surfactants.

    Science.gov (United States)

    Qu, Ailan; Wen, Xiufang; Pi, Pihui; Cheng, Jiang; Yang, Zhuoru

    2008-01-01

    The composite particles with core/shell structure resulting from the combination of silica seed and hydrophobic copolymer (dodecafluoroheptyl methacrylate (DFMA), gamma-methacryloxypropyltriisopropoxidesilane (MAPTIPS), methyl methacrylate, butyl acrylate) were synthesized by emulsion polymerization. The amount of the silica seeds, concentration of reactive surfactant, as well as the addition of DFMA and MAPTIPS, have strong influences on the morphology of composite particles. It has been shown that it would be possible to produce stable organic/inorganic composite particles with inhomogeneous core/shell structure encapsulated by hydrophobic fluorinated acrylate even though using unmodified silica particles and admixture of anionic and nonionic surfactants. However, there was an obvious difference on the morphologies of core-shell structure whether the DFMA and MAPTIPS were added or not. It was concluded that two kinds of polymerization approaches might coexist in the presence of DFMA and MAPTIPS for raw silica. One clear advantage of this process is that there is only one silica bead for each composite particle. This kind of stable core-shell structural hybrid latex is useful for preparing high performance hydrophobic coating.

  9. Monodisperse nonionic isoprenoid-type hexahydrofarnesyl ethylene oxide surfactants: high throughput lyotropic liquid crystalline phase determination.

    Science.gov (United States)

    Fong, Celesta; Weerawardena, Asoka; Sagnella, Sharon M; Mulet, Xavier; Krodkiewska, Irena; Chong, Josephine; Drummond, Calum J

    2011-03-15

    The neat and lyotropic phase behavior of eight new ethylene oxide amphiphiles (EO = 1-8) with a hexahydrofarnesyl chain (3,7,11-trimethyldodecyl) and narrow polydispersity (>98.5% purity) is reported. Below five EO units the behavior of the neat surfactants show only a glass transition, Tg ∼ -90 °C. Above four EO units, crystallization (Tcrys) and crystal-isotropic liquid (Tm) transitions are also observed that increase with degree of ethoxylation of the surfactant headgroup. The lyotropic liquid crystalline phase behavior spans a complex spectrum of surfactant-water interfacial curvatures. Specifically, inverse phases are present below ambient temperatures for EO ethoxylation, with the crossover to normal phases occurring at HFarn(EO)(7-8) which exhibits normal hexagonal (H(I)) and cubic (Q(I)) phases at ambient temperatures. The toxicity of colloidal dispersions of these EO amphiphiles was assayed against normal breast epithelial (HMEpiC) and breast cancer (MCF7) cell lines. The IC50 of the EO amphiphiles was similar in both cell lines with moderate toxicity ranging from ca. <5 to 140 μM in an in vitro cell viability assay. Observations are qualitatively rationalized in terms of the molecular geometry of the surfactant. The physicochemical behavior of the HFarnesyl ethylene oxide amphiphiles is compared to other ethylene oxide surfactants.

  10. Self-assembly in dilute mixtures of non-ionic and anionic surfactants and rhamnolipd biosurfactants.

    Science.gov (United States)

    Liley, J R; Penfold, J; Thomas, R K; Tucker, I M; Petkov, J T; Stevenson, P S; Banat, I M; Marchant, R; Rudden, M; Terry, A; Grillo, I

    2017-02-01

    The self-assembly of dilute aqueous solutions of a ternary surfactant mixture and rhamnolipid biosurfactant/surfactant mixtures has been studied by small angle neutron scattering. In the ternary surfactant mixture of octaethylene glycol monododecyl ether, C12E8, sodium dodecyl 6-benzene sulfonate, LAS, and sodium dioxyethylene monododecyl sulfate, SLES, small globular interacting micelles are observed over the entire composition and concentration range studied. The modelling of the scattering data strongly supports the assumption that the micelle compositions are close to the solution compositions. In the 5-component rhamnolipid/surfactant mixture of the mono-rhamnose, R1, di-rhamnose, R2, rhamnolipids with C12E8/LAS/SLES, globular micelles are observed over much of the concentration and composition range studied. However, for solutions relatively rich in rhamnolipid and LAS, lamellar/micellar coexistence is observed. The transition from globular to more planar structures arises from a synergistic packing in the 5 component mixture. It is not observed in the individual components nor in the ternary C12E8/LAS/SLES mixture at these relatively low concentrations. The results provide an insight into how synergistic packing effects can occur in the solution self-assembly of complex multi-component surfactant mixtures, and give rise to an unexpected evolution in the phase behaviour.

  11. Modulation of the photophysical properties of curcumin in nonionic surfactant (Tween-20) forming micelles and niosomes: a comparative study of different microenvironments.

    Science.gov (United States)

    Mandal, Sarthak; Banerjee, Chiranjib; Ghosh, Surajit; Kuchlyan, Jagannath; Sarkar, Nilmoni

    2013-06-13

    The modulation of the photophysical properties of curcumin inside two different types of microenvironments provided by nonionic surfactant forming micelles and vesicles (niosomes) has been investigated using steady state and time-resolved fluorescence spectroscopy. The formation of small unilamellar Tween-20/cholesterol niosomes with narrow size distribution has been successfully demonstrated by means of dynamic light scattering (DLS) and transmission electron microscopy (TEM) techniques. Our results indicate that niosomes are a better possible delivery system than the conventional surfactants forming normal micelles to suppress the level of degradation of curcumin. The enhanced fluorescence intensity along with the significant blue-shift in the emission maxima of curcumin upon encapsulation into the hydrophobic microenvironments of micelles and niosomes is a consequence of the reduced interaction of curcumin with the water molecules. We found that the more rigid and confined microenvironment of niosomes enhances the steady state fluorescence intensity along with the fluorescence lifetime of curcumin more than in micelles. The rigidity of the niosome membrane which arises basically due to the presence of cholesterol molecules increases the level of interaction between curcumin and the oxoethylene units of Tween-20 molecules. It is also possible for the hydroxyl groups of the cholesterol moieties to form intermolecular hydrogen bonds with curcumin to perturb nonradiative deactivation mechanism through excited state intramolecular hydrogen atom transfer (ESIHT).

  12. Determination of non-ionic polyethoxylated surfactants in wastewater and river water by mixed hemimicelle extraction and liquid chromatography-ion trap mass spectrometry.

    Science.gov (United States)

    Cantero, Manuel; Rubio, Soledad; Pérez-Bendito, Dolores

    2005-03-04

    The capability of hemimicelles-based solid phase extraction (SPE)/liquid chromatography/atmospheric pressure chemical ionisation in positive mode, ion trap mass spectrometry (LC/(APCl+-IT)-MS) for the concentration, separation and quantitation of non-ionic surfactants has been investigated. Concentration was based on the formation of mixed aggregates of analytes [alkylphenol ethoxylates (APE, octyl and nonyl) and alkyl ethoxylates (AE, C12-C16)] with the anionic surfactant sodium dodecyl sulphate (SDS) that is adsorbed on alumina. Parameters affecting SPE were investigated on the basis that hemimicelles are dynamic entities in equilibrium with the aqueous phase. The performance of ion trap mass spectrometry for MS and MS/MS quantitation of non-ionic homologues was assessed. Recoveries of analytes from wastewater influent and effluent and river water samples ranged between 91 and 98% and were found independent on the length of the alkyl chain under the optimised conditions. Anionic surfactants did not interfere to the levels found in environmental samples. The detection limits ranged between 14 and 111 ng/l for wastewater influent, 10 and 40 for wastewater effluent and 4 and 35 for river water, after concentration of 250, 500 and 750 ml of sample, respectively. The approach was applied to the determination of AE and APE in influent and effluent samples from four wastewater treatment plants and four river samples. The concentrations of individual non-ionic surfactants found ranged between 0.3 and 373 microg/l.

  13. Characterization of polysorbate 85, a nonionic surfactant, by liquid chromatography vs. ion mobility separation coupled with tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Solak Erdem, Nilüfer; Alawani, Nadrah; Wesdemiotis, Chrys, E-mail: wesdemiotis@uakron.edu

    2014-01-15

    Graphical abstract: -- Highlights: •Liquid chromatography (LC) separates amphiphilic blends according to hydrophobicity. •Ion mobility (IM) spectrometry separates these blends based on molecular size/shape. •LC–MS provides the separation resolution needed for quantifying fatty acid content. •IM–MS enables rapid, solvent-free separation and the detection of trace components. •With either method, tandem MS allows to count the hydrophobic substituents. -- Abstract: Liquid chromatography (LC) and ion mobility (IM) separation have been coupled with mass spectrometry (MS) and tandem mass spectrometry (MS{sup 2}) to characterize a commercially important nonionic surfactant, polysorbate 85. The constituents of this amphiphilic blend contained a sorbitan or isosorbide core that was chain extended with poly(ethylene oxide) (PEO) and partially esterified at the PEO termini with oleic acid or, to a lesser extent, other fatty acids. Using interactive LC in reverse-phase mode, the oligomers of the surfactant were separated according to their hydrophobicity/hydrophilicity balance. On the other hand, IM spectrometry dispersed the surfactant oligomers by their charge and collision cross section (i.e. size/shape). With either separation method, an increased number of fatty ester groups and/or lack of the polar sorbitan (or isosorbide) core led to higher retention/drift times, enabling the separation of isobaric species or species with superimposed isotope patterns, so that their ester content could be conclusively identified by MS{sup 2}. LC–MS and IM–MS permitted the detection of several byproducts besides the major PEO-sorbitan oleate oligomers. LC–MS provides the separation resolution needed for quantitative determination of the degree of esterification. IM–MS, which minimizes analysis time and solvent use, is ideally suitable for a fast, qualitative survey of samples differing in their minor constituents or impurities.

  14. Synergetic effect of benzotriazole and non-ionic surfactant on copper chemical mechanical polishing in KIO{sub 4}-based slurries

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Liang [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Center for Advanced Materials Processing, Clarkson University, Potsdam, NY 13699 (United States); He, Yongyong [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China); Niu, Xiangyu; Li, Yuzhuo [Center for Advanced Materials Processing, Clarkson University, Potsdam, NY 13699 (United States); Luo, Jianbin, E-mail: luojb@tsinghua.edu.cn [State Key Laboratory of Tribology, Tsinghua University, Beijing 100084 (China)

    2014-05-02

    Ruthenium will be integrated into copper interconnects as a barrier layer in the near future. During the chemical mechanical polishing process of the ruthenium barrier layer, copper polishing performance with barrier slurries is crucial to microchips' final performance. This paper mainly studies the synergetic effect of benzotriazole (BTA) and non-ionic surfactant on copper polishing performance using KIO{sub 4}-based barrier slurries. The results show that, the copper removal rate (RR) and static etching rate increase with increasing concentration of KIO{sub 4} due to the increasing proportion of the Cu–periodate and Cu–iodate compounds like Cu(IO{sub 4}){sub 2} and Cu(IO{sub 3}){sub 2} of the passivating film on the copper surface; the added BTA can further enhance the copper RR instead of suppressing it probably due to the formation of incomplete Cu–BTA thin film. It is demonstrated that the combination of BTA and non-ionic surfactant exhibits excellent performance in suppressing the copper RR to about 200 Å/min, realizing satisfactory copper surface quality and achieving desirable material removal rate selectivity among copper, ruthenium and low-κ dielectrics. The synergetic passivation mechanism of BTA and non-ionic surfactant on the copper surface was investigated. It is proposed that in the presence of KIO{sub 4} as an oxidizer, the added BTA and non-ionic surfactant can form a porous passivating film on the copper surface which is mainly composed of the Cu–BTA complex, the adsorbed non-ionic surfactant and the leftover insoluble copper compounds like Cu(IO{sub 4}){sub 2} and Cu(IO{sub 3}){sub 2}, and then the hydrophobic polypropylene oxide segments of non-ionic surfactant can be effectively absorbed on the hydrophobic Cu–BTA complex as a supplement. The above two parts are integrated into a complete passivating film to protect the copper surface from chemical dissolution and excessive mechanical abrasion. - Highlights: • The copper

  15. Viscoelasticity and microstructure of non-ionic microemulsions

    NARCIS (Netherlands)

    Eshuis, A.; Mellema, J.

    1984-01-01

    Non-ionic microemulsions were investigated by viscoelastic measurements in the kHz region. We found that in some parts of the phase diagram our systems consisted of a dispersion of spherical oil doplets, stabilized by a non-ionic surfactant, in a continuous phase of almost pure water. Because of the

  16. Sorption of a nonionic surfactant Tween 80 by minerals and soils.

    Science.gov (United States)

    Kang, Soyoung; Jeong, Hoon Young

    2015-03-02

    Batch experiments were conducted to evaluate Tween 80 sorption by oxides, aluminosilicates, and soils. For oxides, the sorption by silica and alumina follow linear isotherms, and that by hematite follows a Langmuir isotherm. Considering isotherm type and surface coverage, Tween 80 may partition into the silica/alumina-water interface, whereas it may bind to hematite surface sites. Among aluminosilicates, montmorillonite shows the greatest sorption due to the absorption of Tween 80 into interlayers. For other aluminosilicates, it sorbs to surfaces, with the sorption increasing as plagioclaseTween 80 sorption. The greater sorption by untreated soils than H2O2-treated soils indicates that soil organic matter is a vital sorbent. The sorption hysteresis, contributed to by clay minerals and soil organic matter, is characterized by the greater sorption during the desorption than the sorption stages. This suggests the potential difficulty in removing surfactants from soils. Also, sorption of surfactants can adversely affect surfactant-enhanced remediation by decreasing the aquifer permeability and the availability of surfactants for micellar solubilization.

  17. Sorption of a nonionic surfactant Tween 80 by minerals and soils

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Soyoung, E-mail: soyoung@pusan.ac.kr; Jeong, Hoon Young, E-mail: hjeong@pusan.ac.kr

    2015-03-02

    Highlights: • Tween 80 sorption varies significantly among soil minerals. • Sorption mechanisms and atomic compositions explain to mineral-specific sorption. • Clay minerals and SOM in soils are the key contributors to Tween 80 sorption. • Hysteresis suggests the potential difficulty in removing residual surfactants. - Abstract: Batch experiments were conducted to evaluate Tween 80 sorption by oxides, aluminosilicates, and soils. For oxides, the sorption by silica and alumina follow linear isotherms, and that by hematite follows a Langmuir isotherm. Considering isotherm type and surface coverage, Tween 80 may partition into the silica/alumina–water interface, whereas it may bind to hematite surface sites. Among aluminosilicates, montmorillonite shows the greatest sorption due to the absorption of Tween 80 into interlayers. For other aluminosilicates, it sorbs to surfaces, with the sorption increasing as plagioclase < vermiculite < kaolinite. This results from the relative reactivity among surface sites: ≡NaOH, ≡CaOH << ≡SiOH < ≡AlOH. Experiments using dry- and wet-sieved soils reveal that fine-grained clay minerals, difficult to separate by dry-sieving, contribute significantly to Tween 80 sorption. The greater sorption by untreated soils than H{sub 2}O{sub 2}-treated soils indicates that soil organic matter is a vital sorbent. The sorption hysteresis, contributed to by clay minerals and soil organic matter, is characterized by the greater sorption during the desorption than the sorption stages. This suggests the potential difficulty in removing surfactants from soils. Also, sorption of surfactants can adversely affect surfactant-enhanced remediation by decreasing the aquifer permeability and the availability of surfactants for micellar solubilization.

  18. Adsorption at air-water and oil-water interfaces and self-assembly in aqueous solution of ethoxylated polysorbate nonionic surfactants.

    Science.gov (United States)

    Penfold, Jeffrey; Thomas, Robert K; Li, Peixun X; Petkov, Jordan T; Tucker, Ian; Webster, John R P; Terry, Ann E

    2015-03-17

    The Tween nonionic surfactants are ethoxylated sorbitan esters, which have 20 ethylene oxide groups attached to the sorbitan headgroup and a single alkyl chain, lauryl, palmityl, stearyl, or oleyl. They are an important class of surfactants that are extensively used in emulsion and foam stabilization and in applications associated with foods, cosmetics and pharmaceuticals. A range of ethoxylated polysorbate surfactants, with differing degrees of ethoxylation from 3 to 50 ethylene oxide groups, have been synthesized and characterized by neutron reflection, small-angle neutron scattering, and surface tension. In conjunction with different alkyl chain groups, this provides the opportunity to modify their surface properties, their self-assembly in solution, and their interaction with macromolecules, such as proteins. Adsorption at the air-water and oil-water interfaces and solution self-assembly of the range of ethoxylated polysorbate surfactants synthesized are presented and discussed.

  19. Solubility of diazepam and prazepam in aqueous non-ionic surfactants.

    Science.gov (United States)

    Moro, M E; Velazquez, M M; Cachaza, J M; Rodriguez, L J

    1986-04-01

    The solubility of diazepam and prazepam in aqueous polyoxyethylen-10-dodecanol, polyoxyethylen-23-dodecanol and polyoxyethylen-20-hexadecanol, has been determined at 25.0 degrees C. Diazepam seems to achieve a higher micellar penetration than prazepam, in spite of an expected smaller hydrophobic character. Thermodynamic interpretation of the micellar solutions is carried out using the regular solutions approach. A surfactant-independent relation between solubilities of both drugs has been derived.

  20. The effect of ionic and non-ionic surfactants on the growth, nitrate reductase and nitrite reductase activities of Spirodela polyrrhiza (L. Schleiden

    Directory of Open Access Journals (Sweden)

    Józef Buczek

    2014-01-01

    Full Text Available Inclusion into the medium of 5 mg•dm-3 of non-ionic (ENF or ionic (DBST surfactant caused 50-60% inhibition of nitrite reductase MR activity in S. polyrrhiza. At the same time, increased accumulation of NO2- in the plant tissues and lowering of the total and soluble protein contents were found. DBST also lowered the nitrate reductase (NR activity and the dry mass of the plants.

  1. Utilizing surfactants to control the sorption, desorption, and biodegradation of phenanthrene in soil-water system.

    Science.gov (United States)

    Jin, Haiwei; Zhou, Wenjun; Zhu, Lizhong

    2013-07-01

    An integrative technology including the surfactant enhanced sorption and subsequent desorption and biodegradation of phenanthrene in the soil-water system was introduced and tested. For slightly contaminated agricultural soils, cationic-nonionic mixed surfactant-enhanced sorption of organic contaminants onto soils could reduce their transfer to plants, therefore safe-guarding agricultural production. After planting, residual surfactants combined with added nonionic surfactant could also promote the desorption and biodegradation of residual phenanthrene, thus providing a cost-effective pollution remediation technology. Our results showed that the cationic-nonionic mixed surfactants dodecylpyridinium bromide (DDPB) and Triton X-100 (TX100) significantly enhanced soil retention of phenanthrene. The maximum sorption coefficient Kd of phenanthrene for contaminated soils treated by mixed surfactants was about 24.5 times that of soils without surfactant (Kd) and higher than the combined effects of DDPB and TX100 individually, which was about 16.7 and 1.5 times Kd, respectively. On the other hand, TX100 could effectively remove phenanthrene from contaminated soils treated by mixed surfactants, improving the bioavailability of organic pollutants. The desorption rates of phenanthrene from these treated soils were greater than 85% with TX100 concentration above 2000 mg/L and approached 100% with increasing TX100 concentration. The biodegradation rates of phenanthrene in the presence of surfactants reached over 95% in 30 days. The mixed surfactants promoted the biodegradation of phenanthrene to some extent in 10-22 days, and had no obvious impact on phenanthrene biodegradation at the end of the experiment. Results obtained from this study provide some insight for the production of safe agricultural products and a remediation scheme for soils slightly contaminated with organic pollutants.

  2. Enhanced photocatalytic degradation of norfloxacin in aqueous Bi2WO6 dispersions containing nonionic surfactant under visible light irradiation.

    Science.gov (United States)

    Tang, Lin; Wang, Jiajia; Zeng, Guangming; Liu, Yani; Deng, Yaocheng; Zhou, Yaoyu; Tang, Jing; Wang, Jingjing; Guo, Zhi

    2016-04-05

    Photocatalytic degradation is an alternative method to remove pharmaceutical compounds in water, however it is hard to achieve efficient rate because of the poor solubility of pharmaceutical compounds in water. This study investigated the photodegradation of norfloxacin in a nonionic surfactant Triton-X100 (TX100)/Bi2WO6 dispersion under visible light irradiation (400-750nm). It was found that the degradation of poorly soluble NOF can be strongly enhanced with the addition of TX100. TX100 was adsorbed strongly on Bi2WO6 surface and accelerated NOF photodegradation at the critical micelle concentration (CMC=0.25mM). Higher TX100 concentration (>0.25mM) lowered the degradation rate. In the presence of TX100, the degradation rate reached the maximum value when the pH value was 8.06. FTIR analyses demonstrated that the adsorbed NOF on the catalyst was completely degraded after 2h irradiation. According to the intermediates identified by HPLC/MS/MS, three possible degradation pathways were proposed to include addition of hydroxyl radical to quinolone ring, elimination of piperazynilic ring in fluoroquinolone molecules, and replacement of F atoms on the aromatic ring by hydroxyl radicals. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Study of monoprotic acid-base equilibria in aqueous micellar solutions of nonionic surfactants using spectrophotometry and chemometrics.

    Science.gov (United States)

    Babamoradi, Hamid; Abdollahi, Hamid

    2015-10-05

    Many studies have shown the distribution of solutes between aqueous phase and micellar pseudo-phase in aqueous micellar solutions. However, spectrophotometric studies of acid-base equilibria in these media do not confirm such distribution because of the collinearity between concentrations of chemical species in the two phases. The collinearity causes the number of detected species to be equal to the number of species in a homogenous solution that automatically misinterpreted as homogeneity of micellar solutions, therefore the collinearity is often neglected. This interpretation is in contradiction to the distribution theory in micellar media that must be avoided. Acid-base equilibrium of an indicator was studied in aqueous micellar solutions of a nonionic surfactant to address the collinearity using UV/Visible spectrophotometry. Simultaneous analysis (matrix augmentation) of the equilibrium and solvation data was applied to eliminate the collinearity from the equilibrium data. A model was then suggested for the equilibrium that was fitted to the augmented data to estimate distribution coefficients of the species between the two phases. Moreover, complete resolution of concentration and spectral profiles of species in each phase was achieved.

  4. Synthesis and Characterization of Encapsulated Nanosilica Particles with an Acrylic Copolymer by in Situ Emulsion Polymerization Using Thermoresponsive Nonionic Surfactant

    Directory of Open Access Journals (Sweden)

    Daryoosh Vashaee

    2013-08-01

    Full Text Available Nanocomposites of encapsulated silica nanoparticles were prepared by in situ emulsion polymerization of acrylate monomers. The synthesized material showed good uniformity and dispersion of the inorganic components in the base polymer, which enhances the properties of the nanocomposite material. A nonionic surfactant with lower critical solution temperature (LCST was used to encapsulate the silica nanoparticles in the acrylic copolymer matrix. This in situ method combined the surface modification and the encapsulation in a single pot, which greatly simplified the process compared with other conventional methods requiring separate processing steps. The morphology of the encapsulated nanosilica particles was investigated by dynamic light scattering (DLS and transmission electron microscopy (TEM, which confirmed the uniform distribution of the nanoparticles without any agglomerations. A neat copolymer was also prepared as a control sample. Both the neat copolymer and the prepared nanocomposite were characterized by Fourier transform infrared spectroscopy (FTIR, thermal gravimetric analyses (TGA, dynamic mechanical thermal analysis (DMTA and the flame resistance test. Due to the uniform dispersion of the non-agglomerated nanoparticles in the matrix of the polymer, TGA and flame resistance test results showed remarkably improved thermal stability. Furthermore, DMTA results demonstrated an enhanced storage modulus of the nanocomposite samples compared with that of the neat copolymer, indicating its superior mechanical properties.

  5. Confinement of a nonionic surfactant membrane within a montmorillonite as a new way to prepare organoclay materials

    Energy Technology Data Exchange (ETDEWEB)

    Guegan, Regis, E-mail: regis.guegan@univ-orleans.fr [Universite d' Orleans (France); Giovanela, Marcelo [Universidade de Caxias do Sul (UCS), RS (Brazil)

    2016-11-15

    The aim of this study was to prepare and characterize a hybrid layered material (organoclay) with a Na-montmorillonite and the triethylene glycol mono-n-decyl ether (C{sub 10}E{sub 3} ) nonionic surfactant which forms a lamellar phase at room temperature. The synthesized organoclay was characterized by complementary techniques (Fourier transform infrared spectroscopy and X-ray diffraction). Experiments in conjunction with electron density analysis showed that a bilayer or membrane of C{sub 10}E{sub 3} was intercalated within the interlayer space of a naturally exchanged Na-montmorillonite. The intercalation of a bilayer of C{sub 10}E{sub 3} in a clay mineral offers new perspectives for the manufacturing of nanomaterials. While showing a hydrophobic surface and a large interlayer space value, the resulting organoclay preserves the compensating cations within the interlayer space allowing one to perform ion exchanges, making easier the intercalation of further organic molecules of important size with functional properties or for environmental purposes. (author)

  6. Coarse-graining MARTINI model for molecular-dynamics simulations of the wetting properties of graphitic surfaces with non-ionic, long-chain and T-shaped surfactants

    CERN Document Server

    Sergi, Danilo; Ortona, Alberto

    2012-01-01

    We report on a molecular dynamics investigation of the wetting properties of graphitic surfaces by various solutions at concentrations 1-8 wt% of commercially available non-ionic surfactants with long hydrophilic chains, linear or T-shaped. These are surfactants of length up to 160 [\\AA]. It turns out that molecular dynamics simulations of such systems ask for a number of solvent particles that can be reached without seriously compromising computational efficiency only by employing a coarse-grained model. The MARTINI force field with polarizable water offers a framework particularly suited for our problem. In general, its advantages over other coarse-grained models are the possibility to explore faster long time scales and the wider range of applicability. Although the accuracy is sometimes put under question, the results for the wetting properties by pure water are in good agreement with those for the corresponding atomistic systems and theoretical predictions. On the other hand, the bulk properties of vario...

  7. Sphere-to-Rod Transitions of Nonionic Surfactant Micelles in Aqueous Solution Modeled by Molecular Dynamics Simulations

    NARCIS (Netherlands)

    Velinova, Maria; Sengupta, Durba; Tadjer, Alia V.; Marrink, Siewert-Jan

    2011-01-01

    Control of the size and agglomeration of micellar systems is important for pharmaceutical applications such as drug delivery. Although shape-related transitions in surfactant solutions are studied experimentally, their molecular mechanisms are still not well understood. In this study, we use coarse-

  8. Millimeter-wave sensor based on a λ/2-line resonator for identification and dielectric characterization of non-ionic surfactants.

    Science.gov (United States)

    Rodilla, H; Kim, A A; Jeffries, G D M; Vukusic, J; Jesorka, A; Stake, J

    2016-01-20

    Studies of biological and artificial membrane systems, such as niosomes, currently rely on the use of fluorescent tags, which can influence the system under investigation. For this reason, the development of label-free, non-invasive detection techniques is of great interest. We demonstrate an open-volume label-free millimeter-wave sensing platform based on a coplanar waveguide, developed for identification and characterization of niosome constituents. A design based on a λ/2-line resonator was used and on-wafer measurements of transmission and reflection parameters were performed up to 110 GHz. Our sensor was able to clearly distinguish between common niosome constituents, non-ionic surfactants Tween 20 and Span 80, measuring a resonance shift of 3 GHz between them. The complex permittivities of the molecular compounds have been extracted. Our results indicate insignificant frequency dependence in the investigated frequency range (3 GHz - 110 GHz). Values of permittivity around 3.0 + 0.7i and 2.2 + 0.4i were obtained for Tween 20 and Span 80, respectively.

  9. Excitation energy transfer in europium chelate with doxycycline in the presence of a second ligand in micellar solutions of nonionic surfactants

    Science.gov (United States)

    Smirnova, T. D.; Shtykov, S. N.; Kochubei, V. I.; Khryachkova, E. S.

    2011-01-01

    The complexation of Eu3+ with doxycycline (DC) antibiotic in the presence of several second ligands and surfactant micelles of different types is studied by the spectrophotometric and luminescence methods. It is found that the efficiency of excitation energy transfer in Eu3+-DC chelate depends on the nature of the second ligand and surfactant micelles. Using thenoyltrifluoroacetone (TTA) as an example, it is shown that the second ligand additionally sensitizes the europium fluorescence, and the possibility of intermediate sensitization of DC and then of europium is shown by the example of 1,10-phenanthroline. In all cases, the excitation energy transfer efficiency was increased due to the so-called antenna effect. The decay kinetics of the sensitized fluorescence of the binary and mixed-ligand chelates in aqueous and micellar solutions of nonionic surfactants is studied and the relative quantum yields and lifetimes of fluorescence are determined.

  10. Effect of inorganic additives on solutions of nonionic surfactants V: Emulsion stability.

    Science.gov (United States)

    Schott, H; Royce, A E

    1983-12-01

    Electrolytes often break emulsions to which they were added as active ingredients, adjuvants, or impurities. The stability of oil-in-water emulsions containing octoxynol 9 NF as the emulsifier and various added electrolytes was investigated by measuring droplet size, turbidity, and oil separation on storage at various temperatures and in a centrifugal field at 25 degrees. Electrolytes were added to hexadecane emulsions after emulsification (direct addition); alternatively, hexadecane was emulsified in octoxynol 9-electrolyte mixtures (reverse addition). Xylene emulsions were prepared by direct addition only. Hexadecane emulsions containing 0.10% octoxynol 9 were considerably more stable than xylene emulsions containing 0.60% because the surfactant is practically insoluble in hexadecane, but miscible in all proportions with xylene. An emulsifier soluble in the disperse phase as well as the continuous phase evidently forms less stable interfacial films. The electrolytes investigated were sulfuric and hydrochloric acids, magnesium nitrate, and aluminum nitrate, which salt octoxynol 9 in by complexation between its ether groups and their cations; sodium thiocyanate, which salts the surfactant in by destructuring water; and sodium chloride and sodium sulfate, which salt octoxynol 9 out. The addition of these electrolytes at concentrations up to 2 or 3 m to hexadecane emulsions produced fast and extensive creaming, little or no flocculation, no coalescence, and only minor changes in droplet size or turbidity on storage at room temperature. The extent of coalescence during centrifugation was actually reduced by the additives. Such stability is unusual. Droplet size and turbidity depended mainly on octoxynol 9 concentration. The greatest decrease in the former and increase in the latter occurred when the concentration was increased from 0.10 to approximately 0.4%. All emulsions became slightly coarser on storage at 25 degrees. Stability at 50 degrees was impaired by

  11. Use of mixtures containing nonionic surfactants in the destabilization of petroleum emulsions

    Energy Technology Data Exchange (ETDEWEB)

    Mansur, Claudia R.E.; Mauro, Aparecida C.; Aquino, Aline S.; Lechuga, Fernanda C.; Gonzalez, Gaspar; Lucas, Elizabete F. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Macromoleculas; Gonzalez, Gaspar [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

    2004-07-01

    During the petroleum dehydration process, it is necessary to used chemical demulsifiers in order to break the w/o emulsions that are formed in the oil field. These demulsifiers products are, in many cases, surfactants based poly(ethylene oxide-propylene oxide) block copolymers (PEO-PPO), with different EO/PO molar ratio. In this work were correlate the structure and the properties of PEO-PPO block copolymers with their performance as petroleum emulsion-destabilizing agent. Moreover, it was used an additive in the formulations, known as hydrotrope, in order to increase the solubility of these copolymers in aqueous solution. The results showed that the copolymer branched, whose hydrophilic segments (PEO and OH) are in an external adjacent position, present the higher solubility, in spite of to own EO/PO ratio similar to the others copolymers and the highest molar mass. Moreover, this copolymer presented the best efficiency in the emulsion destabilization. The addition of the hydrotrope NaBMGS to the PEO-PPO copolymers aqueous solutions caused the solubility increasing of these compounds in water. Such additive being used in the demulsifier formulation provoked an efficiency improving on the emulsion breaking process. (author)

  12. Activity, stability and kinetic parameters for -chymotrypsin catalysed reactions in AOT/isooctane reverse micelles with nonionic and zwitterionic mixed surfactants

    Indian Academy of Sciences (India)

    Santosh Kumar Verma; Kallol K Ghosh

    2013-07-01

    Reverse micelles (RMs) of sodium 1,4-bis(2-ethylhexyl)sulphosuccinate (AOT) in nonpolar organic solvents are widely known to have very high solubilization power for water. The method is applied to the hydrolysis of -nitrophenyl acetate (PNPA) catalysed by -chymotrypsin (-CT) in AOT/isooctane/buffer RMs. The increase in -CT activity and stability was an optimum at wo ([H2O]/[AOT]) = 10, z [Isooctane]/[AOT]) = 5. Three typical surfactants were selected based on their head group charges: a non-ionic surfactant Triton-X 100 and two zwitterionic sulphobetaine surfactants of the type CH2+1N+Me2 (CH2)3 SO$^{−}_{3}$ (n = 10; SB3-10, n = 16; SB3-16). The kinetic parameters (such as cat and M) of the -CT at 27°C were determined and compared in the absence and presence of three surfactants. The effect of chain length of zwitterionic surfactant (SB3-10 and SB3-16) on the enzymatic efficacy of -CT as a function of mixed surfactant addition has been investigated in AOT/isooctane RMs at pH 7.75.

  13. Fragment-based approach to calculate hydrophobicity of anionic and nonionic surfactants derived from chromatographic retention on a C18 stationary phase.

    Science.gov (United States)

    Hammer, Jort; Haftka, Joris J-H; Scherpenisse, Peter; Hermens, Joop L M; de Voogt, Pim W P

    2017-02-01

    To predict the fate and potential effects of organic contaminants, information about their hydrophobicity is required. However, common parameters to describe the hydrophobicity of organic compounds (e.g., octanol-water partition constant [KOW ]) proved to be inadequate for ionic and nonionic surfactants because of their surface-active properties. As an alternative approach to determine their hydrophobicity, the aim of the present study was therefore to measure the retention of a wide range of surfactants on a C18 stationary phase. Capacity factors in pure water (k'0 ) increased linearly with increasing number of carbon atoms in the surfactant structure. Fragment contribution values were determined for each structural unit with multilinear regression, and the results were consistent with the expected influence of these fragments on the hydrophobicity of surfactants. Capacity factors of reference compounds and log KOW values from the literature were used to estimate log KOW values for surfactants (log KOWHPLC). These log KOWHPLC values were also compared to log KOW values calculated with 4 computational programs: KOWWIN, Marvin calculator, SPARC, and COSMOThermX. In conclusion, capacity factors from a C18 stationary phase are found to better reflect hydrophobicity of surfactants than their KOW values. Environ Toxicol Chem 2017;36:329-336. © 2016 The Authors. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC.

  14. Non-ionic Surfactants and Non-Catalytic Protein Treatment on Enzymatic Hydrolysis of Pretreated Creeping Wild Ryegrass

    Science.gov (United States)

    Zheng, Yi; Pan, Zhongli; Zhang, Ruihong; Wang, Donghai; Jenkins, Bryan

    Our previous research has shown that saline Creeping Wild Ryegrass (CWR), Leymus triticoides, has a great potential to be used for bioethanol production because of its high fermentable sugar yield, up to 85% cellulose conversion of pretreated CWR. However, the high cost of enzyme is still one of the obstacles making large-scale lignocellulosic bioethanol production economically difficult. It is desirable to use reduced enzyme loading to produce fermentable sugars with high yield and low cost. To reduce the enzyme loading, the effect of addition of non-ionic surfactants and non-catalytic protein on the enzymatic hydrolysis of pretreated CWR was investigated in this study. Tween 20, Tween 80, and bovine serum albumin (BSA) were used as additives to improve the enzymatic hydrolysis of dilute sulfuric-acid-pretreated CWR. Under the loading of 0.1 g additives/g dry solid, Tween 20 was the most effective additive, followed by Tween 80 and BSA. With the addition of Tween 20 mixed with cellulase loading of 15 FPU/g cellulose, the cellulose conversion increased 14% (from 75 to 89%), which was similar to that with cellulase loading of 30 FPU/g cellulose and without additive addition. The results of cellulase and BSA adsorption on the Avicel PH101, pretreated CWR, and lignaceous residue of pretreated CWR support the theory that the primary mechanism behind the additives is prevention of non-productive adsorption of enzymes on lignaceous material of pretreated CWR. The addition of additives could be a promising technology to improve the enzymatic hydrolysis by reducing the enzyme activity loss caused by non-productive adsorption.

  15. Selective adsorption of nonionic surfactant on hexagonal mesoporous silicates (HMSs) in the presence of ionic dyes.

    Science.gov (United States)

    Punyapalakul, Patiparn; Takizawa, Satoshi

    2006-10-01

    Selective adsorption of alkylphenol polyethoxylates (APnEOs) from synthetic textile wastewater was investigated using hexagonal mesoporous silicates (HMSs). HMSs are synthetic silicate that have uniform mesopores, large surface areas and uniform surface functional groups. Five different types of HMSs were synthesized by surfactant-templating methods, and three of them were grafted with organic surface functional groups, i.e., n-octyldimethyl-, 3-aminopropyltriethoxy-, and 3-mercaptopropyl-groups. Titanium-substituted HMS was also made in the same way as HMS. Adsorption capacities and selectivities of these HMSs for APnEOs were investigated in batch adsorption experiments either in single-solute APnEO solutions or in mixed solutions with ionic dyes. Triton X-100 was used as a model APnEO and either Basic Yellow 1 or Acid Blue 45 was used as cationic or anionic dyes, respectively. All the HMSs except 3-aminopropyltriethoxy-grafted HMS had higher adsorption capacities of Triton X-100 than powdered activated carbon. HMS and Ti-HMS had the highest BET surface areas and mesopore volumes measured by the nitrogen adsorption method, and thereby the highest adsorption capacities for Triton X-100. Surface charge was the most important attractive force between HMSs and dyes. FT-IR spectra proved that hydrophilic HMSs adsorbed both Basic Yellow 1 and Acid Blue 45 by hydrogen bonding. Acid-base titration experiments revealed that all the HMSs except 3-aminopropyltriethoxy-grafted HMS were negatively charged at neutral pH, whereas PAC and 3-aminopropyltriethoxy-grafted HMS were positively charged. Due to negative surface charge, the anionic dye (Acid Blue 45) was not adsorbed on the four HMSs, which proves high selectivities of these HMSs for Triton X-100 over Acid Blue 45. On the contrary, a small amount of cationic dye (Basic Yellow 1) was adsorbed on all HMSs, but 3-aminopropyltriethoxy-grafted HMS showed the lowest adsorption capacity for Basic Yellow 1 due to positive

  16. Determination of the critical micelle concentration in simulations of surfactant systems

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Andrew P.; Panagiotopoulos, Athanassios Z., E-mail: azp@princeton.edu [Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544 (United States)

    2016-01-28

    Alternative methods for determining the critical micelle concentration (cmc) are investigated using canonical and grand canonical Monte Carlo simulations of a lattice surfactant model. A common measure of the cmc is the “free” (unassociated) surfactant concentration in the presence of micellar aggregates. Many prior simulations of micellizing systems have observed a decrease in the free surfactant concentration with overall surfactant loading for both ionic and nonionic surfactants, contrary to theoretical expectations from mass-action models of aggregation. In the present study, we investigate a simple lattice nonionic surfactant model in implicit solvent, for which highly reproducible simulations are possible in both the canonical (NVT) and grand canonical (μVT) ensembles. We confirm the previously observed decrease of free surfactant concentration at higher overall loadings and propose an algorithm for the precise calculation of the excluded volume and effective concentration of unassociated surfactant molecules in the accessible volume of the solution. We find that the cmc can be obtained by correcting the free surfactant concentration for volume exclusion effects resulting from the presence of micellar aggregates. We also develop an improved method for determination of the cmc based on the maximum in curvature for the osmotic pressure curve determined from μVT simulations. Excellent agreement in cmc and other micellar properties between NVT and μVT simulations of different system sizes is observed. The methodological developments in this work are broadly applicable to simulations of aggregating systems using any type of surfactant model (atomistic/coarse grained) or solvent description (explicit/implicit)

  17. Investigating the stability of the nonionic surfactants tocopheryl polyethylene glycol succinate and sucrose laurate by HPLC-MS, DAD, and CAD.

    Science.gov (United States)

    Christiansen, Anne; Backensfeld, Thomas; Kühn, Silke; Weitschies, Werner

    2011-05-01

    High-performance liquid chromatography (HPLC) methods using a charged aerosol detector (CAD), a mass selective detector (MSD), and a diode array detector (DAD) were developed to characterize the nonionic surfactants d-α-tocopheryl polyethylene glycol (1000) succinate (TPGS) and Surfhope sugar ester D-1216 (sucrose laurate). The molecular structure and the heterogeneous composition resulting from different isomers and various lengths of polyethylene glycol (PEG) chains make it difficult to develop sensitive and specific analytical methods for both surfactants. Hence, there is lack of knowledge about the stability and grade of impurity of these compounds. Sucrose laurate does not possess any chromophore, thus UV detection is not applicable. Therefore, CAD and MSD have been used for determination. The aim of the study was to characterize these nonionic surfactants and to examine chemical stability at pH 1.0 and 37 °C, simulating harsh gastric conditions. It was shown that both compounds are liable to degradation under these conditions. Sucrose monolaurate exhibited a massive degradation within 8 h incubation due to cleavage of the glycosidic bondage. About 50% of sucrose monolaurate broke down, whereas a marginal amount of 3.4% (± 0.4%) of TPGS degraded into d-α-tocopheryl succinate and the associated PEG chain.

  18. Effects of Film Elasticity and Surface Forces on the Stability of Foams and Lamellae Films in the Presence of Non-ionic Surfactants

    Science.gov (United States)

    Wang, Liguang; Yoon, Roe-Hoan

    2008-07-01

    This paper describes the basic factors affecting the stability of the foam films produced in the presence of nonionic surfactants such as n-pentanol, n-octanol, methyl isobutyl carbinol (MIBC), and polypropylene glycol (PPG). We used a model developed by Wang and Yoon (Colloids and Surfaces A: Physicochem. Eng. Aspects 282-283, 84-91 (2006)) to calculate the Gibbs elasticity of the lamellae films. In addition, we used the thin film pressure balance (TFPB) technique to measure film thicknesses. The results were used to determine the disjoining pressures in the thin lamellae (foam) films formed between air bubbles, which are relevant forces governing the final drainage stage of foam films before reaching either equilibrium or rupture. The film elasticity and surface forces data were then compared with the foam stabilities measured in the present work in the presence of the various surfactants. It was found that foam stabilities are controlled both by film elasticity and by surface forces, the relative contributions of each changing with surfactant type and concentration. In general, surface forces play a more important role at relatively low surfactant concentrations, while elasticity plays a more important role at higher concentrations. At the surfactant additions usually employed in the mining industry, MIBC stabilizes foams by increasing disjoining pressures, while PPG-400 stabilizes foams by increasing film elasticity.

  19. Organophilization of bentonite clays with non-ionic surfactants aiming their use in drilling fluids base oil; Organofilizacao de argilas bentoniticas com tensotivo nao-ionico visando seu uso em fluidos de perfuracao base oleo

    Energy Technology Data Exchange (ETDEWEB)

    Silva, I.A.; Costa, J.M.R.; Neves, G.A.; Ferreira, H.C. [Universidade Federal de Campina Grande (UAEMa/CCT/UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais; Ferreira, H.S. [Universidade Federal da Paraiba (DEMAT/CT/UFPB), Joao Pessoa, PB (Brazil). Dept. de Materiais

    2010-07-01

    The use of nonionic surfactants has been replacing the traditional ionic surfactants among others by its high potential for resistance to thermal degradation. This work aims at the development of organoclay by the addition of nonionic surfactants for use in drilling fluids for oil wells based oil. The bentonite clay was organophilized and then characterized by X-ray diffraction and swelling Foster, seeking the most appropriate choice of surfactant to liquid organic dispersing media: ester, diesel and paraffin. With the obtained dispersions were measured apparent viscosities and plastic. The results showed that incorporation of surfactants used in the clay interlayer spacing increased significantly and that the dispersions showed rheological properties within the specifications of PETROBRAS, for the use of organophilic clays in drilling fluids in a non-aqueous base. (author)

  20. Properties of aqueous solutions of nonionic surfactants, Triton X-114 and Tween 80, at temperatures from 293 to 318 K: Spectroscopic and ultrasonic studies

    Science.gov (United States)

    Szymczyk, Katarzyna; Taraba, Anna

    2017-02-01

    The speed of sound, density and refractive index of aqueous solutions of the nonionic surfactants, p-(1,1,3,3-tetramethylbutyl) phenoxypoly(ethyleneglycol) Triton X-114 (TX114) and polysorbate 80, Tween 80, have been measured over the entire range of concentration at 293, 298, 303, 308, 313 and 318 K under atmospheric pressure. Steady state fluorescence measurements have been also made using pyrene as a probe. From the experimental data the quantities such as critical micelle concentration (CMC), apparent dielectric constant, hydration number, isentropic compressibility, apparent specific adiabatic compressibility of a solute, intermolecular free length, acoustic impedance and molar sound number were determined. The variation of these parameters with concentration and temperature was discussed in terms of intermolecular interactions in the solution of a given surfactant.

  1. Fabrication of highly conductive and transparent thin films from single-walled carbon nanotubes using a new non-ionic surfactant via spin coating.

    Science.gov (United States)

    Jo, Jea Woong; Jung, Jae Woong; Lee, Jea Uk; Jo, Won Ho

    2010-09-28

    Oligothiophene-terminated poly(ethylene glycol) was synthesized and used as a non-ionic and amphiphilic surfactant for fabricating high-quality single-walled carbon nanotube (SWCNT) films by a simple spin coating method. The absence of charge repulsion between SWCNT/surfactant complexes successfully leads to formation of a dense network of SWCNTs on the substrate through a single deposition of spin coating. When the SWCNT film was treated with nitric acid and thionyl chloride after washed with dichloromethane and water, a high-performance SWCNT film with the sheet resistance of 59 ohm/sq and the transparency of 71% at 550 nm was successfully obtained. Since the SWCNT film exhibits a high value of σ(dc)/σ(ac) (∼17) and excellent dimensional stability after releasing from the substrate, the film can be used as a transparent electrode in flexible optoelectronic devices.

  2. Novel non-ionic surfactant proniosomes for transdermal delivery of lacidipine: optimization using 2(3) factorial design and in vivo evaluation in rabbits.

    Science.gov (United States)

    Soliman, Sara M; Abdelmalak, Nevine S; El-Gazayerly, Omaima N; Abdelaziz, Nabaweya

    2016-06-01

    Proniosomes offer a versatile vesicle drug delivery concept with potential for delivery of drugs via transdermal route. To develop proniosomal gel using cremophor RH 40 as non-ionic surfactant containing the antihypertensive drug lacidipine for transdermal delivery so as to avoid its extensive first pass metabolism and to improve its permeation through the skin. Proniosomes containing 1% lacidipine were prepared by the coacervation phase separation method, characterized, and optimized using a 2(3) full factorial design to define the optimum conditions to produce proniosomes with high entrapment efficiency, minimal vesicle size, and high-percentage release efficiency. The amount of cholesterol (X1), the amount of soya lecithin (X2), and the amount of cremophor RH 40 (X3) were selected as three independent variables. The system F4 was found to fulfill the maximum requisite of an optimum system because it had minimum vesicle size, maximum EE, maximum release efficiency, and maximum desirability. The optimized system (F4) was then converted to proniosomal gel using carbopol 940 (1% w/w). In vitro permeation through excised rabbit skin study revealed higher flux (6.48 ± 0.45) for lacidipine from the optimized proniosomal gel when compared with the corresponding emulgel (3.04 ± 0.13) mg/cm(2)/h. The optimized formulation was evaluated for its bioavailability compared with commercial product. Statistical analysis revealed significant increase in AUC (0 - α) 464.17 ± 113.15 ng h/ml compared with 209.02 ± 47.35 ng h/ml for commercial tablet. Skin irritancy and histopathological investigation of rat skin revealed its safety. Cremophor RH 40 proniosomal gel could be considered as very promising nanocarriers for transdermal delivery of lacidipine.

  3. Preparation of graphene/TiO{sub 2} composites by nonionic surfactant strategy and their simulated sunlight and visible light photocatalytic activity towards representative aqueous POPs degradation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Kexin; Xiong, Jingjing; Chen, Tong [Provincial Key Laboratory of Ecological Diagnosis-Remediation and Pollution Blocking Technology, Department of Environment and Chemical Engineering, Nanchang Hangkong Uuniversity, Nanchang 330063 (China); Yan, Liushui, E-mail: yanliushui1964@yahoo.cn [Provincial Key Laboratory of Ecological Diagnosis-Remediation and Pollution Blocking Technology, Department of Environment and Chemical Engineering, Nanchang Hangkong Uuniversity, Nanchang 330063 (China); Dai, Yuhua; Song, Dongyang; Lv, Ying; Zeng, Zhenxing [Provincial Key Laboratory of Ecological Diagnosis-Remediation and Pollution Blocking Technology, Department of Environment and Chemical Engineering, Nanchang Hangkong Uuniversity, Nanchang 330063 (China)

    2013-04-15

    Highlights: ► A series of graphene/TiO{sub 2} composites were developed by nonionic surfactant strategy. ► The textural property, optical property, and composition were well characterized. ► Aqueous POPs were degraded under simulated sunlight and visible light irradiation. ► The degradation mechanism and kinetics of aqueous POPs were studied in detail. ► Mineralization of aqueous POPs and recyclability of the composites were also tested. -- Abstract: A series of graphene/TiO{sub 2} composites were fabricated using a single-step nonionic surfactant strategy combined with the solvothermal treatment technique. Their phase structure, morphology, porosity, optical absorption property, as well as composition and structure, were characterized. The as-prepared composites were successfully applied to degrade aqueous persistent organic pollutants (POPs) such as rhodamine B, aldicarb, and norfloxacin in simulated sunlight (λ > 320 nm) and visible light (λ > 400 nm) irradiation. The degradation mechanism and kinetics of aqueous POPs were studied in detail. The mineralization of aqueous POPs and the recyclability of the composites were also tested in the same condition.

  4. Adsorption of proteins at the solution/air interface influenced by added nonionic surfactants at very low concentrations for both components. 3. Dilational surface rheology.

    Science.gov (United States)

    Fainerman, V B; Aksenenko, E V; Lylyk, S V; Lotfi, M; Miller, R

    2015-03-05

    The influence of the addition of the nonionic surfactants C12DMPO, C14DMPO, C10OH, and C10EO5 at concentrations between 10(-5) and 10(-1) mmol/L to solutions of β-casein (BCS) and β-lactoglobulin (BLG) at a fixed concentration of 10(-5) mmol/L on the dilational surface rheology is studied. A maximum in the viscoelasticity modulus |E| occurs at very low surfactant concentrations (10(-4) to 10(-3) mmol/L) for mixtures of BCS with C12DMPO and C14DMPO and for mixtures of BLG with C10EO5, while for mixture of BCS with C10EO5 the value of |E| only slightly increased. The |E| values calculated with a recently developed model, which assumes changes in the interfacial molar area of the protein molecules due to the interaction with the surfactants, are in satisfactory agreement with experimental data. A linear dependence exists between the ratio of the maximum modulus for the mixture to the modulus of the single protein solution and the coefficient reflecting the influence of the surfactants on the adsorption activity of the protein.

  5. A linear relation between the cloud point and the number of oxyethylene units of water-soluble nonionic surfactants valid for the entire range of ethoxylation.

    Science.gov (United States)

    Schott, Hans

    2003-04-01

    The following linear equation correlates the cloud point (CP) of water-soluble polyoxyethylated nonionic surfactants (NSs) with the average number p of oxyethylene units per molecule: (p - p0)/CP = a + b(p - p0). Here p0 is the smallest value of p that confers solubility in cold water: In a homologous series of NSs, it belongs to the surfactant with CP = 0 degrees C. Plots of CP versus p for five representative homologous series of NSs consist of three segments: A steeply ascending, nearly straight line, a transition region that ranges from p = 15-22 to p = 20-28, and a nearly horizontal plateau that approaches asymptotically the CPs of polyethylene glycols with molecular weights between 30,000 and 4400. These CPs range from 113 to 130 degrees C. Most CPs for NSs were taken from the literature or measured on commercially available samples; eight CPs above 100 degrees C were measured on newly synthesized surfactants. Previously published linear equations correlating CP with p cover only NSs with p or = 100. It can be used for selecting specific NSs for high-temperature applications. The hydrophile-lipophile balance of the surfactant with p = p0 oxyethylene units, namely, HLB0, is a novel quantitative measure of the hydrophobicity of the hydrocarbon moiety of the relevant homologous NS series. Its value reflects the size, composition, and structure of the hydrocarbon moiety.

  6. EVALUATION OF THE USEFULNESS OF CONTINUOUS FLOW ANALYSIS FOR THE STUDY OF ANIONIC SURFACTANTS AND NONIONIC SURFACTANTS IN WATER AND SEWAGE SAMPLES

    Directory of Open Access Journals (Sweden)

    Aleksandra Strugała-Wilczek

    2014-10-01

    Established methods show low limit of detection, good precision and good correctness. The described full automatic method takes effect in short-time analysis, small sample volume required for testing and waste restriction. Proposed flow injection system comply with requirements and may be successfully applied in monitoring studies as well as in the routine laboratory analysis. Rapid determination of water and waste water quality by the SFA for the content of surfactants allows an adequate response in case of exceeding the permissible concentrations, even according to the most restricted requirements.

  7. Acute toxicity and relationship between metabolites and ecotoxicity during the biodegradation process of non-ionic surfactants: fatty-alcohol ethoxylates, nonylphenol polyethoxylate and alkylpolyglucosides.

    Science.gov (United States)

    Jurado, E; Fernández-Serrano, M; Núñez-Olea, J; Luzón, G; Lechuga, M

    2009-01-01

    The toxicity values of fatty-alcohol ethoxylates, nonylphenol polyethoxylate, and alkylpolyglucosides have been determined by applying assays with luminescent bacteria. Also, the relation between metabolites and ecotoxicity during the biodegradation process has been determined. The biodegradation tests were carried out according to the OECD 301 E test for ready biodegradability. In these tests a solution of the surfactant, representing the sole carbon source for the microorganisms, was tested in a mineral medium, inoculated and incubated under aerobic conditions in the dark. The toxicity of surfactants is related to their molecular structure (Quantitative Structure Activity Relationships, QSAR). For the alkylpolyglucosides, toxicity expressed as EC(50) is related with the critical micelle concentration (CMC), the hydrophilic-lipophilic balance (HLB) of the surfactant, and the hydrophobic alkyl chain (R). The results indicate that toxicity increased as the CMC decreased and as the hydrophobicity increased and R rose. For fatty-alcohol ethoxylates, parameters characteristic studied have been HLB, number of units of ethylene oxide and the alkyl chain length. Relationships found are in agreement with the fact that increasing the alkyl chain length leads to a lower EC(50), whereas increasing ethoxylation leads to a lower toxicity. An analysis of the behaviour of the toxicity and HLB again indicates that the toxicity was greater for surfactants with a smaller HLB. The evolution of the toxicity was studied over the biodegradation process, expressed as a percentage of inhibition. For all the non-ionic surfactants assayed, except for the nonylphenol polyethoxylate, a major decline was found in toxicity during the first days of the biodegradation assay and at all the concentrations tested.

  8. Effects of Concentration and Conformation of Surfactants on Phase Separation of Surfactant-Water-Oil Systems

    Institute of Scientific and Technical Information of China (English)

    袁银权; 邹宪武; 刘昊阳

    2004-01-01

    The effects of surfactants on the phase separation of surfactant-water-oil systems have been investigated by using discontinuous molecular dynamic simulations. The phase separation speed and equilibrium configuration are dependent on the surfactant concentration and conformation. The equilibrium concentration of surfactants at the interface remains constant. With the increasing surfactant concentration, the equilibrium configuration crosses over from the disperse phase to the bicontinuous one. The crossover concentration is estimated. The conformation of the surfactant has little effect on the equilibrium concentration of surfactants at the interface,while it affects the equilibrium configuration after phase separation.

  9. Adsorption of Anionic, Cationic and Nonionic Surfactants on Carbonate Rock in Presence of ZrO 2 Nanoparticles

    Science.gov (United States)

    Esmaeilzadeh, Pouriya; Bahramian, Alireza; Fakhroueian, Zahra

    The adsorption of surfactants at the solid-water interface is important for the control of wetting, lubrication, detergency and in mineral flotation.We have studied the adsorptions of different types of surfactants, cationic (Dodecyl trimethylammonium bromide, DTAB), anionic (sodium dodecyl sulfate, SDS) and non-anionic (lauryl alcohol-7 mole ethoxylate, LA7) on carbonate rock in presence of zirconium oxide spherical nanoparticles (17-19 nm). ZrO2 nanoparticles with tetrahedral structure have significant effect on adsorption of surfactants on the carbonate rock. We have used the measured conductivities to determine the rate of adsorption of surfactants at rock-water interfaces. The conductivity of DTAB in aqueous solutions containing calcite powder decreases more than the other surfactants in contact with ZrO2 nanoparticles. We have also investigated the adsorption of surfactants at the air-water interface. The presence of nanoparticles, as demonstrated by our experiments, enhances the surface activity and surface adsorption of the surfactants through electrostatic forces or formation of nanostructures. Dynamic light structuring data shows similar aggregation number of nanoparticles in presence of nanoparticles.

  10. Studies on interfacial behavior and wettability change phenomena by ionic and nonionic surfactants in presence of alkalis and salt for enhanced oil recovery

    Science.gov (United States)

    Kumar, Sunil; Mandal, Ajay

    2016-05-01

    Surfactant flooding is one of the most promising method of enhanced oil recovery (EOR) used after the conventional water flooding. The addition of alkali improves the performance of surfactant flooding due to synergistic effect between alkali and surfactant on reduction of interfacial tension (IFT), wettability alteration and emulsification. In the present study the interfacial tension, contact angle, emulsification and emulsion properties of cetyltrimethylammonium bromide (CTAB), sodium dodecyl sulfate (SDS) and polysorbate 80 (Tween 80) surfactants against crude oil have been investigated in presence of sodium chloride (NaCl) and alkalis viz. sodium hydroxide (NaOH), sodium carbonate (Na2CO3), ammonium hydroxide (NH4OH), sodium metaborate (SMB) and diethanolamine (DEA). All three surfactants significantly reduce the IFT values, which are further reduced to ultra-low value (∼10-4 mN/m) by addition of alkalis and salt. It has been found experimentally that alkali-surfactant systems change the wettability of an intermediate-wet quartz rock to water-wet. Emulsification of crude oil by surfactant and alkali has also been investigated in terms of the phase volume and stability of emulsion. A comparative FTIR analysis of crude oil and different emulsions were performed to investigate the interactions between crude oil and displacing water in presence of surfactant and alkali.

  11. Lycopene recovery from tomato peel under mild conditions assisted by enzymatic pre-treatment and non-ionic surfactants.

    Science.gov (United States)

    Papaioannou, Emmanouil H; Karabelas, Anastasios J

    2012-01-01

    The tomato processing industry generates large quantities of tomato peel residues, usually creating environmental problems. These residues are a significant source of lycopene, thus providing an attractive alternative for profitable handling of these otherwise problematic by-products. The enzymatic pretreatment of these residues for lycopene recovery has already been employed, although the use of surfactants for enhancing the recovery has not been examined so far. The enzymatic pretreatment of tomato peels, using two commercially available pectinolytic enzyme preparations, was evaluated suggesting that there is an optimum pretreatment time of about 1 h, enzyme amount 250 Units/mL and no significant pH influence. Lycopene surfactant - assisted extraction was further investigated, showing that, among eight surfactants used, the most suitable was "Span 20", with an optimum ratio of 6-7 surfactant molecules per lycopene molecule. Sequential enzymatic pretreatment and surfactant-assisted extraction (30 min for each step) was evaluated leading to an improved lycopene extraction yield, with a somewhat smaller surfactant molar ratio (i.e. 4-5). In the latter case, the yield of lycopene recovery was almost four times greater compared to just 1 hr enzymatic pretreatment, and was approximately ten times greater compared to the recovery from untreated peels. Furthermore, such lipophilic compound recovery, avoiding the use of organic solvents, is environmentally attractive and ensures direct lycopene use in the food and cosmetics industries.

  12. Effect of Different Surfactants on the Interfacial Behavior of the n-Hexane-Water System in the Presence of Silica Nanoparticles.

    Science.gov (United States)

    Biswal, Nihar Ranjan; Rangera, Naveen; Singh, Jayant K

    2016-07-28

    This paper presents the effect of negatively charged silica nanoparticles (NPs) on the interfacial tension of the n-hexane-water system at variable concentrations of four different surfactants, viz., an anionic surfactant, sodium dodecyl sulfate (SDS), a cationic surfactant, cetyltrimethylammonium bromide (CTAB), and two nonionic surfactants, Tween 20 and Triton X-100 (TX-100). The presence of negatively charged silica nanoparticles is found to have a different effect depending on the type of surfactant. In the case of ionic surfactants, SDS and CTAB, silica NPs reduce the interfacial tension of the system. On the contrary, for nonionic surfactants, Tween 20 and TX-100, silica NPs increase the interfacial tension. The increasing/decreasing nature of the interfacial tension in the presence of NPs is well supported by the calculated surface excess concentrations. The diffusion kinetic control (DKC) and statistical rate theory (SRT) models are used to understand the behavior of dynamic interfacial tension of the surfactant-NP-oil-water system. The DKC model is found to describe the studied surfactant-NP-oil-water systems more aptly.

  13. Foaming and foam stability for mixed polymer-surfactant solutions: effects of surfactant type and polymer charge.

    Science.gov (United States)

    Petkova, R; Tcholakova, S; Denkov, N D

    2012-03-20

    Solutions of surfactant-polymer mixtures often exhibit different foaming properties, compared to the solutions of the individual components, due to the strong tendency for formation of polymer-surfactant complexes in the bulk and on the surface of the mixed solutions. A generally shared view in the literature is that electrostatic interactions govern the formation of these complexes, for example between anionic surfactants and cationic polymers. In this study we combine foam tests with model experiments to evaluate and explain the effect of several polymer-surfactant mixtures on the foaminess and foam stability of the respective solutions. Anionic, cationic, and nonionic surfactants (SDS, C(12)TAB, and C(12)EO(23)) were studied to clarify the role of surfactant charge. Highly hydrophilic cationic and nonionic polymers (polyvinylamine and polyvinylformamide, respectivey) were chosen to eliminate the (more trivial) effect of direct hydrophobic interactions between the surfactant tails and the hydrophobic regions on the polymer chains. Our experiments showed clearly that the presence of opposite charges is not a necessary condition for boosting the foaminess and foam stability in the surfactant-polymer mixtures studied. Clear foam boosting (synergistic) effects were observed in the mixtures of cationic surfactant and cationic polymer, cationic surfactant and nonionic polymer, and anionic surfactant and nonionic polymer. The mixtures of anionic surfactant and cationic polymer showed improved foam stability, however, the foaminess was strongly reduced, as compared to the surfactant solutions without polymer. No significant synergistic or antagonistic effects were observed for the mixture of nonionic surfactant (with low critical micelle concentration) and nonionic polymer. The results from the model experiments allowed us to explain the observed trends by the different adsorption dynamics and complex formation pattern in the systems studied.

  14. Physico-chemical study of new non-ionic surfactants. Influence of ions on aggregation properties; Etude physico-chimique de nouveaux tensioactifs complexants thermoreversibles. Influence d'ions reconnus et non reconnus sur les proprietes d'agregation

    Energy Technology Data Exchange (ETDEWEB)

    Coulombeau, H

    2003-01-01

    New di-block thermo-sensitive metal chelating surfactants have been synthesised. They are based on polyethoxylated non-ionic surfactants (CiEj). A lysine block is linked either to the extremity of a CiEj (surfactant 2) or in a branched position (surfactant 1). These molecules retain the cloud point and the surface-active properties exhibited by the CiEj surfactants. Moreover they possess good complexing properties towards certain ions, which allows them to be successfully applied to cloud point extraction. In both cases, the cloud point and the area per headgroup at the air-water interface are higher than those of the analogous CiEj, which shows the hydrophilic contribution of the lysine block. Macroscopic properties (phase diagrams) and microscopic properties (shape of the aggregates and interactions between them) of the water-surfactant systems have been studied at ambient temperature. Small angle X-Rays scattering (SAXS) and small angle neutrons scattering (SANS) have shown that the new di-block surfactants form spherical micelles at low concentrations. The influence of non complexed salts on the new surfactants is the same as on classical CiEj: salting-in and salting-out phenomena occur according to the Hofmeister series. The effect of a complexed ion, uranyl cation, is however unusual: it leads to a sphere to rod transition, in turn lowering significantly the cloud point, which goes against the expectations on basis of the Hofmeister series. Finally, a preliminary study of ternary mixtures, water-surfactant 1-oil, is presented. It revealed the formation of microemulsions and pointed out that the surfactant film is then a lot more rigid than that formed with classical CiEj. (author)

  15. Response of graywater recycling systems based on hydroponic plant growth to three classes of surfactants

    Science.gov (United States)

    Garland, J. L.; Levine, L. H.; Yorio, N. C.; Hummerick, M. E.

    2004-01-01

    Anionic (sodium laureth sulfate, SLES), amphoteric (cocamidopropyl betaine, CAPB) and nonionic (alcohol polyethoxylate, AE) surfactants were added to separate nutrient film technique (NFT) hydroponic systems containing dwarf wheat (Triticum aestivum cv. USU Apogee) in a series of 21 day trials. Surfactant was added either in a (1). temporally dynamic mode (1-3 g surfactant m(-2) growing area d(-1)) as effected by automatic addition of a 300 ppm surfactant solution to meet plant water demand, or (2). continuous mode (2 g surfactant m(-2) growing area d(-1)) as effected by slow addition (10 mLh(-1)) of a 2000 ppm surfactant solution beginning at 4d after planting. SLES showed rapid primary degradation in both experiments, with no accumulation 24 h after initial addition. CAPB and AE were degraded less rapidly, with 30-50% remaining 24 h after initial addition, but CAPB and AE levels were below detection limit for the remainder of the study. No reductions in vegetative growth of wheat were observed in response to SLES, but biomass was reduced 20-25% with CAPB and AE. Microbial communities associated with both the plant roots and wetted hardware surfaces actively degraded the surfactants, as determined by monitoring surfactant levels following pulse additions at day 20 (with plants) and day 21 (after plant removal). In order to test whether the biofilm communities could ameliorate phytotoxicity by providing a microbial community acclimated for CAPB and AE decay, the continuous exposure systems were planted with wheat seeds after crop removal at day 21. Acclimation resulted in faster primary degradation (>90% within 24h) and reduced phytotoxicity. Overall, the studies indicate that relatively small areas (3-5m(2)) of hydroponic plant systems can process per capita production of mixed surfactants (5-10 g x person(-1)d(-1)) with minimal effects on plant growth.

  16. Response of graywater recycling systems based on hydroponic plant growth to three classes of surfactants

    Science.gov (United States)

    Garland, J. L.; Levine, L. H.; Yorio, N. C.; Hummerick, M. E.

    2004-01-01

    Anionic (sodium laureth sulfate, SLES), amphoteric (cocamidopropyl betaine, CAPB) and nonionic (alcohol polyethoxylate, AE) surfactants were added to separate nutrient film technique (NFT) hydroponic systems containing dwarf wheat (Triticum aestivum cv. USU Apogee) in a series of 21 day trials. Surfactant was added either in a (1). temporally dynamic mode (1-3 g surfactant m(-2) growing area d(-1)) as effected by automatic addition of a 300 ppm surfactant solution to meet plant water demand, or (2). continuous mode (2 g surfactant m(-2) growing area d(-1)) as effected by slow addition (10 mLh(-1)) of a 2000 ppm surfactant solution beginning at 4d after planting. SLES showed rapid primary degradation in both experiments, with no accumulation 24 h after initial addition. CAPB and AE were degraded less rapidly, with 30-50% remaining 24 h after initial addition, but CAPB and AE levels were below detection limit for the remainder of the study. No reductions in vegetative growth of wheat were observed in response to SLES, but biomass was reduced 20-25% with CAPB and AE. Microbial communities associated with both the plant roots and wetted hardware surfaces actively degraded the surfactants, as determined by monitoring surfactant levels following pulse additions at day 20 (with plants) and day 21 (after plant removal). In order to test whether the biofilm communities could ameliorate phytotoxicity by providing a microbial community acclimated for CAPB and AE decay, the continuous exposure systems were planted with wheat seeds after crop removal at day 21. Acclimation resulted in faster primary degradation (>90% within 24h) and reduced phytotoxicity. Overall, the studies indicate that relatively small areas (3-5m(2)) of hydroponic plant systems can process per capita production of mixed surfactants (5-10 g x person(-1)d(-1)) with minimal effects on plant growth.

  17. Recent progress of the characterization of oppositely charged polymer/surfactant complex in dilution deposition system.

    Science.gov (United States)

    Miyake, M

    2017-01-01

    A mixture of oppositely charged polymer and surfactants changes the solubilized state, having a complex precipitation region at the composition of electric neutralization. This complex behavior has been applied to surface modification in the fields of health care and cosmetic products such as conditioning shampoos, as a dilution-deposition system in which the polymer/surfactant mixture at the higher surfactant concentration precipitates the insoluble complex by dilution. A large number of studies over many years have revealed the basic coacervation behavior and physicochemical properties of complexes. However, the mechanism by which a precipitated complex performs surface modification is not well understood. The precipitation region and the morphology of precipitated complex that are changed by molecular structure and additives affect the performance. Hydrophilic groups such as the EO unit in polymers and surfactants, the mixing of nonionic or amphoteric surfactant and nonionic polymer, and the addition of low polar solvent influence the complex precipitation region. Furthermore, the morphology of precipitated complex is formed by crosslinking and aggregating among polymers in the dilution process, and characterizes the performance of products. The polymer chain density in precipitated complex is determined by the charges of both the polymer and surfactant micelle and the conformation of polymer. As a result, the morphology of precipitated complexes is changed from a closely packed film to looser meshes, and/or to small particles, and it is possible for the morphology to control the rheological properties and the amount of adsorbed silicone. In the future, further investigation of the relationships between the morphology and performance is needed.

  18. Research Progress on Removal Method of Nonionic Surfactant in Wastewater%废水中非离子表面活性剂去除的研究进展

    Institute of Scientific and Technical Information of China (English)

    那仁格日勒; 唐楷; 樊义康; 杨益祥; 邹伟; 颜杰

    2015-01-01

    非离子表面活性剂因独特的性能被广泛应用于国民生产生活的各个领域,但大量未经任何处理的含非离子表面活性剂的废水直接排放到自然界中,带来严重的环境污染。本文通过比较和总结近年来含表面活性剂污水中非离子表面活性剂的脱除方法,希望为含非离子表面活性剂污水的处理找一种切实可行的方法,减轻环境的污染。%As its unique properties, the nonionic surfactants had been applied extensively in the field of domestic production and life. However, untreated wastewater with nonionic surfactants had been directly discharged to the nature, which caused serious environmental problems. In this paper, the removal methods of nonionic surfactants in wastewater were compared and summarized. To reduce environmental pollution, a practicable method may be found in the treatment prospectively.

  19. Effects of pig manure compost and nonionic-surfactant Tween 80 on phenanthrene and pyrene removal from soil vegetated with Agropyron elongatum.

    Science.gov (United States)

    Cheng, K Y; Lai, K M; Wong, J W C

    2008-10-01

    This paper evaluates the effects of pig manure compost (PMC) and Tween 80 on the removal of phenanthrene (PHE) and pyrene (PYR) from soil cultivated with Agropyron elongatum. Soils spiked with about 300 mg kg(-1) of PHE and PYR were individually amended with 0%, 2.5%, 5% and 7.5% (dry wt) of PMC or 0, 20 and 100 mg kg(-1) of Tween 80. Unplanted and sterile microcosms were prepared as the controls. PAH concentration, total organic matter (TOM), dissolved organic carbon (DOC), total heterotrophic and PAH degrading microbial populations in soil were quantified before and after 60d period. The results indicated that A. elongatum could significantly enhance PYR removal (from 46% to 61%) but had less impact on PHE removal (from 96% to 97%). Plant uptake of the PAHs was insignificant. Biodegradation was the key mechanism of PAH removals (Tween 80 levels increased the removal of PYR but not of PHE. Maximal PYR removal of 79% and 92% were observed in vegetated soil receiving 100 mg kg(-1) Tween 80 and 7.5% PMC, respectively. Enhanced PYR removal in soil receiving PMC could be explained by the elevated levels of DOC, TOM and microbial populations as suggested by Pearson correlation test. While the positive effect of Tween 80 on PYR removal could probably due to its capacities to enhance PYR bioavailability in soil. This paper suggests that the addition of either PMC or nonionic-surfactant Tween 80 could facilitate phytoremediation of PAH contaminated soil.

  20. Production and application of nonionic surfactant-fatty methyl ester ethoxys%脂肪酸甲酯乙氧基化物FMEE的生产与应用

    Institute of Scientific and Technical Information of China (English)

    徐铭勋

    2012-01-01

    Fatty acid methyl ester ethoxyes (FMEE) is a low foam non-ionic surfactant, the FMEE's production and related application performance, including resistance to hard water, cleaning property, low-temperature fluidity, ecological environmental protection and other properties were discussed. On the other hand, paper-making, floatation, hard surface cleaning, textile dyeing and finishing, and other fields related applications were also explored in this paper.%脂肪酸甲酯乙氧基化物(FMEE)是一种低泡沫的非离子表面活性剂,本文探讨了FMEE的生产工艺与相关应用性能,包括耐硬水、净洗性能、低温流动性、生态环保等性质,也探索了其在造纸、煤碳浮选、硬表面清洗、纺织印染等领域相关应用.

  1. 阴-非双子表面活性剂用于中性脱墨研究%Application of anionic - nonionic Gemini surfactants in neutral deinking of waste paper

    Institute of Scientific and Technical Information of China (English)

    陈红; 朱宝伟; 张丹; 赵威

    2015-01-01

    Efficacy for neutral deinking of waste recycled newspaper with laboratory prepared new anionic -nonionic Gemini surfactant was examined. Via orthogonal designed tests,the optimal operating conditions for the neutral deinking process were identified as follows:deinking agent dosage,0. 8% (refer to mass of dry waste newspaper):pulping time,3 h;flotation time,30 min;curing time,50 min;curing temperature,50 ℃. The deinking efficacy of the new anionic - nonionic Gemini surfactants was compared separately with that of conventional anionic and nonionic surfactants,and the experimental results showed that the former is better. Meanwhile,the deinking efficacy of the blend of the new anionic - nonionic Gemini surfactant with other surfactants was also examined and the results showed that there is good synergistic effect between the new Gemini surfactant and other surfactants.%以干废旧报纸为研究对象,考察了自制阴-非双子(Gemini)表面活性剂的中性脱墨效果,通过正交试验确定了较佳的脱墨条件为:脱墨剂用量为干废旧报纸质量的0.8%,碎浆时间3 h,浮选时间30 min,熟化时间50 min,熟化温度50℃。比较了该表面活性剂与阴离子、非离子表面活性剂的脱墨效果,结果表明该表面活性剂的脱墨效果好于所考察的阴离子和非离子表面活性剂。同时还研究了该表面活性剂与其他表面活性剂复配的脱墨效果,结果显示复配后的表面活性剂具有较好的协同作用。

  2. Monitoring corrosion and corrosion control of iron in HCl by non-ionic surfactants of the TRITON-X series - Part III. Immersion time effects and theoretical studies

    Energy Technology Data Exchange (ETDEWEB)

    Amin, Mohammed A., E-mail: maaismail@yahoo.co [Materials and Corrosion Lab (MCL), Department of Chemistry, Faculty of Science, Taif University, 888 Hawaiya, Taif (Saudi Arabia); Department of Chemistry, Faculty of Science, Ain Shams University, 11566 Abbassia, Cairo (Egypt); Ahmed, M.A. [Physics Department, Faculty of Science, Taif University, 888 Hawaiya, Taif (Saudi Arabia); Arida, H.A. [Materials and Corrosion Lab (MCL), Department of Chemistry, Faculty of Science, Taif University, 888 Hawaiya, Taif (Saudi Arabia); Kandemirli, Fatma [Nigde University, Department of Chemistry, 51240 Nigde (Turkey); Saracoglu, Murat [Faculty of Education, Erciyes University, 38039 Kayseri (Turkey); Arslan, Taner [Department of Chemistry, Eskisehir Osmangazi University, 26480 Eskisehir (Turkey); Basaran, Murat A. [Nigde University, Department of Mathematics, 51240 Nigde (Turkey)

    2011-05-15

    Graphical abstract: . Display Omitted Research highlights: The inhibition effect of TX-100, TX-165 and TX-305 on iron corrosion in 1.0 M HCl was studied. TX-305 inhibited iron corrosion more effectively than TX-100 and TX-165. In most cases, inhibition efficiency increased with time during the first 60 min of immersion, then decreased. Calculated quantum chemical parameters confirmed the experimental inhibition efficiencies of the tested surfactants. - Abstract: The inhibition performance of three selected non-ionic surfactants of the TRITON-X series, namely TRITONX-100 (TX-100), TRITON-X-165 (TX-165) and TRITON-X-305 (TX-305), on the corrosion of iron was studied in 1.0 M HCl solutions as a function of inhibitor concentration (0.01-0.20 g L{sup -1}) and immersion time (0.0-8 h) at 298 K. Measurements were conducted based on Tafel polarization, LPR and impedance studies. At high frequencies, the impedance spectrum showed a depressed capacitive loop in the complex impedance plane, whose diameter is a function of the immersion time and the type and concentration of the introduced surfactant. In all cases, an inductive loop was observed in the low frequency and this could be attributed to the adsorption behavior. The inhibition efficiency increased with immersion time, reached a maximum and then decreased. This was attributed to the orientation change of adsorbed surfactant molecules. TX-305 inhibited iron corrosion more effectively than TX-100 and TX-165. The frontier orbital energies, the energy gap between frontier orbitals, dipole moments ({mu}), charges on the C and O atoms, the polarizabilities, and the quantum chemical descriptors were calculated. The quantum chemical calculation results inferred that for the HOMO representing the condensed Fukui function for an electrophilic attack (f{sub k}{sup +}), the contributions belong to the phenyl group and the oxygen atom attached to the phenyl group for each tested surfactant. Quantitative structure

  3. Impact of Surfactant Type on Adsorption Process and Oil Recovery: Implementation of New Surfactant Produced from Zizyphus Spina-Christi Extract

    National Research Council Canada - National Science Library

    Zargartalebi, Mohammad; Barati, Nasim; Pordel Shahri, Mojtaba

    2014-01-01

    Three different types of surfactants containing an anionic, a cationic and a new nonionic biosurfactant, Zizyphus Spina-Christi extract were used for the purpose of oil recovery in a core flood system...

  4. Synthesis of nanosilica from silica fume using an acid-base precipitation technique and PVA as a nonionic surfactant

    Directory of Open Access Journals (Sweden)

    Vajihe Jafari

    2014-12-01

    Full Text Available The purpose of the present study was to synthesize and characterize nanosilica from alkali-extraction of silica fume under controlled conditions using poly (vinyl alcohol (PVA as a dispersing agent. The dissolution efficiency of silica fume was affected by various factors such as concentration of the reagent, reaction time and temperature. A maximum dissolution efficiency of 91% was achieved at the sodium hydroxide solution concentration of 2.5 M, after areaction time of 30 minutes and at areaction temperature of 80°C. The microstructure and morphology of the obtained nanosilica powder at the optimum conditions were characterized using scanning electron microscopy (SEM. SEM images confirmed the formation of smaller and less agglomerated nanosilica particles due to the existence of the surfactant. Further, the synthesized nanosilica was characterized by Fourier transform infrared (FTIR spectroscopy, X-ray diffractometry (XRF and X-ray diffraction (XRD. The results show that the synthesized nanosilica consisted of pure silica particles.

  5. Soil flushing of cresols contaminated soil: application of nonionic and ionic surfactants under different pH and concentrations.

    Science.gov (United States)

    Gitipour, Saeid; Narenjkar, Khadijeh; Sanati Farvash, Emad; Asghari, Hossein

    2014-01-01

    In this study, the viability of soil flushing on the removal of cresols (meta-, ortho-, and para-cresols) from contaminated soil has been investigated. High production and distribution of cresols in the environment indicate their potential for a widespread exposure to humans. The presence of these compounds in soil could cause a significant threat to environment, as they are toxic and refractory in nature. Cresols are persistent chemicals which are classified by the United State Environmental Protection Agency (U.S.EPA) as Group C, possible human carcinogens. Soil flushing is one of the soil remediation technologies which could by applied for treatment of hydrocarbon contaminated soil. Flushing of the contaminated soil samples was carried out by using sodium dodecyl sulfate (SDS) and Triton X-100 surfactant solutions at the concentrations of 0.1%, 0.2%, 0.3%, and 0.4% (W/W). Three acidic, neutral, and alkaline environments were utilized by adjusting pH of the washing solutions at 3, 7 and 12 to evaluate the effect of washing environment in removing cresols. The results of this research denote that the highest removal efficiencies of 79.6% and 83.51% were achieved for m-cresol and total o- and p-cresols, respectively, under the alkaline environment of pH12 at 0.4% (W/W) SDS concentration. Regarding performance of Triton X-100, the removal efficiencies of 80.26% and 80.14% for the above cresols were attained under similar conditions. Hence, illustrating the effectiveness of surfactants in soil flushing remediation of cresols contaminated soil.

  6. Influence of salts on the coexistence curve and protein partitioning in nonionic aqueous two-phase micellar systems

    Directory of Open Access Journals (Sweden)

    A. M. Lopes

    2014-12-01

    Full Text Available Aqueous two-phase micellar systems (ATPMS can be exploited in separation science for the extraction/purification of desired biomolecules. Prior to phase separation the surfactant solution reaches a cloud point temperature, which is influenced by the presence of electrolytes. In this work, we provide an investigation on the cloud point behavior of the nonionic surfactant C10E4 in the presence of NaCl, Li2SO4 and KI. We also investigated the salts' influence on a model protein partitioning. NaCl and Li2SO4 promoted a depression of the cloud point. The order of salts and the concentration that decreased the cloud point was: Li2SO4 0.5 M > NaCl 0.5 M ≈ Li2SO4 0.2 M. On the other hand, 0.5 M KI dislocated the curve to higher cloud point values. For our model protein, glucose-6-phosphate dehydrogenase (G6PD, partitioning experiments with 0.5 M NaCl or 0.2 M Li2SO4 at 13.85 ºC showed similar results, with K G6PD ~ 0.46. The lowest partition coefficient was obtained in the presence of 0.5 M KI (K G6PD = 0.12, with major recovery of the enzyme in the micelle-dilute phase (%Recovery = 90%. Our results show that choosing the correct salt to add to ATPMS may be useful to attain the desired partitioning conditions at more extreme temperatures. Furthermore, this system can be effective to separate a target biomolecule from fermented broth contaminants.

  7. Influence of nonionic surfactant on electroless copper deposition%非离子型表面活性剂对化学沉铜的影响

    Institute of Scientific and Technical Information of China (English)

    余霞; 胡光辉; 潘湛昌; 庞文萍; 魏志钢; 肖楚民; 张晃初; 曾祥福

    2013-01-01

    Electroless copper plating was carried out with brass sheet as substrate. The basic bath composition and process conditions are as follows: CuSO4·5H2O 10 g/L, EDTA-2Na 40 g/L, NaOH 12 g/L, HCHO 10 mL/L, pH 13.0, temperature 35 ℃, and time 10 min. The effects of nonionic surfactants such as OP-10, Triton X-100, and Tween-80 on the starting time of copper deposition, deposition rate, ductility, and grain refinement of Cu coating were studied. The results showed that the three kinds of surfactant can reduce copper deposition rate. The ductility and grain refinement of copper coating are improved by Triton X-100 and OP-10 when their mass concentration is 1-9 mg/L, while the starting time of copper deposition is delayed. Tween-80 can reduce the deposition rate significantly but has little impact on the ductility of Cu coating. Compared to Triton X-100 and Tween-80, OP-10 is the favorable agent for ductility improvement of electroless Cu coating.%以黄铜片为基体进行化学镀铜,基础镀液组成和工艺条件为:CuSO4·5H2O 10 g/L,EDTA-2Na40 g/L,NaOH 12 g/L,HCHO 10 mL/L,pH 13.0,温度35℃,时间10 min.研究了非离子型表面活性剂OP-10、曲拉通X-100和吐温-80对起镀时间、沉积速率、铜镀层韧性和晶粒细化的影响.结果表明,3种表面活性剂都会降低铜的沉积速率.质量浓度为1 ~9 mg/L时,曲拉通X-100和OP-10都能使铜镀层的韧性改善和晶粒细化,同时延长起镀时间;吐温-80会显著降低铜的沉积速率,但对铜镀层韧性的影响不大.与曲拉通X-100和吐温-80相比,OP-10是较理想的沉铜韧性改善剂.

  8. The stability of non-ionic surfactants and linear alkylbenzene sulfonates in a water matrix and on solid-phase extraction cartridges.

    Science.gov (United States)

    Petrović, M; Barceló, D

    2000-12-01

    The stability of nonylphenol ethoxylates (NPEO), alcohol ethoxylates (AEO), coconut diethanol amides (CDEA) and linear alkylbenzene sulfonates (LAS) in a water matrix and preconcentrated on SPE cartridges was studied. A stability study was carried out in a water matrix (spiked ground water and real-world waste water) comparing different pretreatment procedures (addition of sulfuric acid to pH = 3, preservation with 1% and 3% of formaldehyde). When stored in a water matrix serious qualitative and quantitative changes occurred in waste water during the period of time studied (30 days). The losses of C12-C14 alcohol ethoxylates ranged from 72% to 88% when the sample was preserved with acid and from 17% to 86% when the sample was preserved with formaldehyde (3%). Simultaneously, an enrichment of the shorter alkyl chain homologues (C7EO and C10EO) was observed. The losses of NPEO were from 45% (sample preserved by acidification or by addition of 3% of formaldehyde) to 85% (sample preserved with 1% of formaldehyde). Additionally, an increase in concentration of polyethylene glycols (PEGs) and formation of different acidic forms, such as monocarboxylated (MCPEGs) and dicarboxylated polyethylene glycols (DCPEGs) were observed. The stability of surfactants preconcentrated on SPE cartridges was studied as a function of storage time and storage conditions (room temperature, 4 degrees C and -20 degrees C). The results indicate that disposable SPE cartridges can be recommended for the stabilization of non-ionic surfactants and LAS. Storage at -20 degrees C is feasible for long periods (up to 3 months for ground water and up to 2 months for waste water), while storage at 4 C can be recommended for a maximum of 1 month. When cartridges were kept at -20 degrees C the losses of AEOs (n = 12, 13 and 14), preconcentrated from waste water, ranged from 17 to 29% (after 60 days) and other compounds suffered small losses (maximum of 14% for C13LAS). At room temperature, after 7 days, the

  9. Enhanced photocatalytic degradation of norfloxacin in aqueous Bi{sub 2}WO{sub 6} dispersions containing nonionic surfactant under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Lin, E-mail: tanglin@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Wang, Jiajia [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Zeng, Guangming, E-mail: zgming@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Liu, Yani; Deng, Yaocheng; Zhou, Yaoyu; Tang, Jing; Wang, Jingjing; Guo, Zhi [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China)

    2016-04-05

    Highlights: • TX100 strongly enhanced the adsorption and photodegradation of NOF in Bi{sub 2}WO{sub 6} dispersions under visible light irradiation (400–750 nm). • Cu{sup 2+} (10 mM) significantly suppressed the photocatalytic degradation of NOF. • FT-IR demonstrated that the NOF adsorbed on Bi{sub 2}WO{sub 6} was completely degraded. • Three possible photocatalytic degradation pathways of NOF were proposed, according to the HPLC/MS/MS analysis. - Abstract: Photocatalytic degradation is an alternative method to remove pharmaceutical compounds in water, however it is hard to achieve efficient rate because of the poor solubility of pharmaceutical compounds in water. This study investigated the photodegradation of norfloxacin in a nonionic surfactant Triton-X100 (TX100)/Bi{sub 2}WO{sub 6} dispersion under visible light irradiation (400–750 nm). It was found that the degradation of poorly soluble NOF can be strongly enhanced with the addition of TX100. TX100 was adsorbed strongly on Bi{sub 2}WO{sub 6} surface and accelerated NOF photodegradation at the critical micelle concentration (CMC = 0.25 mM). Higher TX100 concentration (>0.25 mM) lowered the degradation rate. In the presence of TX100, the degradation rate reached the maximum value when the pH value was 8.06. FTIR analyses demonstrated that the adsorbed NOF on the catalyst was completely degraded after 2 h irradiation. According to the intermediates identified by HPLC/MS/MS, three possible degradation pathways were proposed to include addition of hydroxyl radical to quinolone ring, elimination of piperazynilic ring in fluoroquinolone molecules, and replacement of F atoms on the aromatic ring by hydroxyl radicals.

  10. Polymer vs. surfactant : competitive adsorption at the solid-liquid interface

    NARCIS (Netherlands)

    Postmus, B.R.

    2008-01-01

    The research described in this thesis focuses on the competitive adsorption of nonionic polymer and nonionic surfactant on a silica surface. These type of systems are interesting from both an academical and a technological viewpoint. Our academic interest stems simply from the observation that we ha

  11. Effects of Interactions Among Surfactants,Water and Oil on Equilibrium Configuration of Surfactant-Water-Oil Systems

    Institute of Scientific and Technical Information of China (English)

    YUAN Yin-quan; SUN Zhi-bo; XIE Yun; ZOU Xian-wu

    2004-01-01

    The distribution and configuration of surfactants at interface in surfactant-water-oil systems have been investigated using discontinuous molecular dynamic simulations. There exists a certain equilibrium concentration of surfactants at interface for the systems with certain interactions among surfactant, water and oil. The interface length and equilibrium morphology of the systems are dependent on the equilibrium concentration of surfactants at interface and the total amount of surfactants. The interaction strengths among surfactant, water and oil determine the equilibrium concentration of surfactants at interface. Three typical configurations of surfactants at interface have been observed: ① surfactant molecules are perpendicular to the interface and arranged closely; ② perpendicular to the interface and arranged at interval of two particles; ③ lie down in the interface partly.

  12. BEHAVIOR OF SURFACTANT MIXTURES AT SOLID/LIQUID AND OIL/LIQUID INTERFACES IN CHEMICAL FLOODING SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Prof. P. Somasundaran

    2003-03-31

    The aim of the project is to develop a knowledge base to help with the design of enhanced process for mobilizing and extracting untrapped oil. We emphasize on evaluating novel surfactant mixtures and on obtaining optimum combinations of the surfactants in chemical flooding EOR process. An understanding of the micellar shape and size is crucial since these physical properties directly determine the crude oil removal efficiency. Analytical ultracentrifugation experiments were used to test the multi-micelle model proposed earlier and formulate the relationships between mixed micelle formation and the surfactant structure. Information on partial specific volume of surfactants and their mixtures is required to treat analytical ultracentrifuge data. In the last report, it was noted that the partial specific volumes of the sugar-based surfactants obtained experimentally did not agree with those from theoretical calculations. A scrutiny of partial specific volumes of the four sugar-based surfactants revealed that conformational changes upon micelle formation are responsible for the large deviation. From sedimentation equilibrium experiments, two types of micelles were identified for the nonionic polyethylene surfactant and its mixtures with the sugar-based surfactant, dodecyl maltoside. The average aggregation numbers of n-dodecyl-{beta}-D-maltoside and nonyl phenol ethoxylated decyl ether agreed with those reported in literature using other techniques. Our study displayed, for the first time, that small micelles might coexist with large micelles at high concentrations due to unique structures of the surfactant although classical thermodynamic theory supports only one type of micelle. Initial dynamic light scattering results support the results for the same mixed surfactant system from analytical ultracentrifuge equilibrium technique. The implication of this finding lies in the fact that efficiency of oil recovery will be improved due to the large micellar size, its

  13. Rheological Properties of Silica Nanoparticles in Brine and Brine-Surfactant Systems

    Science.gov (United States)

    Pales, Ashley; Kinsey, Erin; Li, Chunyan; Mu, Linlin; Bai, Lingyun; Clifford, Heather; Darnault, Christophe

    2016-04-01

    Rheological Properties of Silica Nanoparticles in Brine and Brine-Surfactant Systems Ashley R. Pales, Erin Kinsey, Chunyan Li, Linlin Mu, Lingyun Bai, Heather Clifford, and Christophe J. G. Darnault Department of Environmental Engineering and Earth Sciences, Laboratory of Hydrogeoscience and Biological Engineering, L.G. Rich Environmental Laboratory, Clemson University, Clemson, SC, USA Nanofluids are suspensions of nanometer sized particles in any fluid base, where the nanoparticles effect the properties of the fluid base. Commonly, nanofluids are water based, however, other bases such as ethylene-glycol, glycerol, and propylene-glycol, have been researched to understand the rheological properties of the nanofluids. This work aims to understand the fundamental rheological properties of silica nanoparticles in brine based and brine-surfactant based nanofluids with temperature variations. This was done by using variable weight percent of silica nanoparticles from 0.001% to 0.1%. Five percent brine was used to create the brine based nanofluids; and 5% brine with 2CMC of Tween 20 nonionic surfactant (Sigma-Aldrich) was used to create the brine-surfactant nanofluid. Rheological behaviors, such as shear rate, shear stress, and viscosity, were compared between these nanofluids at 20C and at 60C across the varied nanoparticle wt%. The goal of this work is to provide a fundamental basis for future applied testing for enhanced oil recovery. It is hypothesized that the addition of surfactant will have a positive impact on nanofluid properties that will be useful for enhance oil recovery. Differences have been observed in preliminary data analysis of the rheological properties between these two nanofluids indicating that the surfactant is having the hypothesized effect.

  14. Sources, transport and reactivity of anionic and non-ionic surfactants in several aquatic ecosystems in SW Spain: A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Lara-Martin, Pablo A. [Departamento de Quimica Fisica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cadiz, Campus Rio San Pedro s/n, 11510 Puerto Real, Cadiz (Spain)], E-mail: pablo.lara@uca.es; Gomez-Parra, Abelardo; Gonzalez-Mazo, Eduardo [Departamento de Quimica Fisica, Facultad de Ciencias del Mar y Ambientales, Universidad de Cadiz, Campus Rio San Pedro s/n, 11510 Puerto Real, Cadiz (Spain)

    2008-11-15

    Presence, distribution and transport mechanisms of the four major synthetic surfactants -linear alkylbenzene sulfonates (LAS), alkyl ethoxysulfates (AES), nonylphenol ethoxylates (NPEOs) and alcohol ethoxylates (AEOs)- have been simultaneously studied in different aquatic ecosystems. Urban wastewater discharges and industrial activities were identified as the main sources for these compounds and their metabolites. LAS, AES and carboxylic metabolites remained in the dissolved form (87-99%). However, NPEOs and AEOs were mostly associated with particulate matter (65-86%), so their degradation in the water column was limited due to their lower bioavailability. It was also observed that sorption to the particulate phase was more intense for longer homologs/ethoxymers for all surfactants. With respect to surface sediments, AES levels were considerably below (<0.25 mg/kg) the values detected for LAS and NPEOs. Concentrations of AEOs, however, were occasionally higher (several tens of ppm) than those found for the rest of the target compounds in several sampling stations. - Occurrence and reactivity of the main synthetic surfactants in freshwater and marine systems are discussed.

  15. Nonionic emulsion-mediated synthesis of zeolite beta

    Indian Academy of Sciences (India)

    Yuguo Shen; Ying Zhang; Chao Jin; Ying Cao; Wei Gao; Lishan Cui

    2011-07-01

    Zeolite beta synthesis was first carried out in a newly developed emulsion system containing nonionic polyoxyethylated alkylphenol surfactant, which showed interesting non-conventional features. Compared to the conventional hydrothermal synthesis of zeolite beta, the reported nonionic emulsion system showed a faster nucleation rate. Furthermore, the emulsion system could stabilize the beta product and retarded its further transformation to ZSM-5 even under the high crystallization temperature at 453 K. Additionally, the beta particle size could be tuned by the adoption of different lengths of alkyl chain in the surfactant and cosurfactant. Control experiments showed each emulsion component played a crucial role in the zeolite beta growth. The approach proposed in this paper might be extended to apply for the syntheses of other types of zeolites with particle size under control.

  16. Structural study of surfactant-dependent interaction with protein

    Energy Technology Data Exchange (ETDEWEB)

    Mehan, Sumit; Aswal, Vinod K., E-mail: vkaswal@barc.gov.in [Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Kohlbrecher, Joachim [Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232 PSI Villigen (Switzerland)

    2015-06-24

    Small-angle neutron scattering (SANS) has been used to study the complex structure of anionic BSA protein with three different (cationic DTAB, anionic SDS and non-ionic C12E10) surfactants. These systems form very different surfactant-dependent complexes. We show that the structure of protein-surfactant complex is initiated by the site-specific electrostatic interaction between the components, followed by the hydrophobic interaction at high surfactant concentrations. It is also found that hydrophobic interaction is preferred over the electrostatic interaction in deciding the resultant structure of protein-surfactant complexes.

  17. Cloud point extraction of copper, lead, cadmium, and iron using 2,6-diamino-4-phenyl-1,3,5-triazine and nonionic surfactant, and their flame atomic absorption spectrometric determination in water and canned food samples.

    Science.gov (United States)

    Citak, Demirhan; Tuzen, Mustafa

    2012-01-01

    A cloud point extraction procedure was optimized for the separation and preconcentration of lead(II), cadmium(II), copper(II), and iron(III) ions in various water and canned food samples. The metal ions formed complexes with 2,6-diamino-4-phenyl-1,3,5-triazine that were extracted by surfactant-rich phases in the nonionic surfactant Triton X-114. The surfactant-rich phase was diluted with 1 M HNO3 in methanol prior to its analysis by flame atomic absorption spectrometry. The parameters affecting the extraction efficiency of the proposed method, such as sample pH, complexing agent concentration, surfactant concentration, temperature, and incubation time, were optimized. LOD values based on three times the SD of the blank (3Sb) were 0.38, 0.48, 1.33, and 1.85 microg/L for cadmium(II), copper(II), lead(II), and iron(III) ions, respectively. The precision (RSD) of the method was in the 1.86-3.06% range (n=7). Validation of the procedure was carried out by analysis of National Institute of Standards and Technology Standard Reference Material (NIST-SRM) 1568a Rice Flour and GBW 07605 Tea. The method was applied to water and canned food samples for determination of metal ions.

  18. Synthesis and application of coconut acid polyether carboxylate anionic-nonionic surfactant for EOR%椰油聚醚羧酸盐阴非离子驱油剂的合成及性能

    Institute of Scientific and Technical Information of China (English)

    鲍新宁; 张卫东; 沙鸥; 李应成

    2015-01-01

    In view of poor universality of conventional surfactants,anionic-nonionic surfactants of coconut acid monoethanol amide polyoxyethylene ether carboxylate with different EOs were synthesized from coco-nut acid monoethanolamide. Structure of products were characterized by IR. Interface properties of the products were investigated. When the concentration of surfactant is 0. 2% in either source well water or sewage water in Zhen 35 block of Jiangsu oil field ,interfacial tension between crude oil and water can reach 10 -3 mN/m order,which can be used to enhance oil recovery.%针对目前常规表面活性剂普适性差的问题,以椰油单乙醇酰胺为原料,制备系列椰油单乙醇酰胺聚氧乙烯醚羧酸盐阴非复合型表面活性剂;用红外光谱进行了表征。测定其界面性能,0.2%表活剂溶液能够使江苏油田真35区块原油分别与水源井水和油田处理站污水,都达到10-3 mN/m数量级的超低界面张力,满足油田驱油要求。

  19. FORMULASI MIKROEMULSI MINYAK DALAM AIR (O/W YANG STABIL MENGGUNAKAN KOMBINASI TIGA SURFAKTAN NON IONIK DENGAN NILAI HLB RENDAH, TINGGI DAN SEDANG Stable O/W Microemulsion Formulation Using Combination of Three Nonionic Surfactants with Low, High and Med

    Directory of Open Access Journals (Sweden)

    Sih Yuwanti

    2012-05-01

    Full Text Available The aim of this research was to determine the proportion of oil, surfactant and water which could produce a stable O/W microemulsion using combination of three nonionic surfactants with low, high and medium HLB values; and to determine the role of surfactant with a medium HLB value in O/W microemulsion formulation. The first group of microemulsions were prepared using combination of Tween 80, Span 80 and Span 40 (80 %:10 %:10 % with dif- ferent proportions of VCO:surfactant (1:3, 1:3.5 dan 1:4.  The second goups of microemulsion were prepared using combination of Tween 80, Span 80 and Span 40 (90 %:5 %:5 % with different proportions of VCO:surfactant 1:4,1:4.5 dan 1:5.  The stability of microemulsion was determined during storage at room temperature and after being ovened at 105 0C 5 hours and centrifuged at 2300 g 15 minutes. Microemulsion stability was determined by measur- ing absorbance of the microemulsion at 502 nm and then converted to turbidity (%.  In order to determine the role of surfactant with a medium HLB value in the formulation of O/W microemulsion, one set microemulsions were made without surfactant with a medium HLB value, and another set of microemulsions were prepared with different ratios of low and medium HLB surfactant (1:1, 2:1 and 1:2. The most stable microemulsion was achieved when the proportion of VCO:surfactant:water was 4:20:76 and combination of Tween 80:Span 80:Span 40 with the ratio of 90:3.33:6.67. A more stable O/W microemulsion could be obtained when surfactant with a medium HLB value was added to O/W microemulsion formulation. Surfactant with a medium HLB value would link the oil phase and water phase with sur- factant layer, interaction of surfactant-oil and surfactant-water increased. It provided a smooth transition between oil phase and water phase, and the microemulsion became more stable. ABSTRAK Tujuan dari penelitian ini adalah untuk menentukan proporsi minyak, surfaktan dan air yang dapat

  20. Partitioning regularity of non-ionic organic mixtures in organic phase/water system

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The partitioning regularity of nonionic organic mixtures in organic phase/water system is revealed. The equation for calculating the partition coefficients of mixtures (KMD), together with the determination model, is derived from the equilibrium partitioning models (EPMs). Based on these derived equations, the KMD values of 20 mixtures conraining halogenated benzenes are obtained. The results show that stronger hydrophobicity of an individual chemical in the mixture results in the stronger hydrophobicity of the mixture and the greater the proportion of this chemical, the stronger the hydrophobicity of the mixture will be. This partitioning regularity is helpful to the study of the toxicity for mixtures and the environmental behavior, such as transfer or accumuiation, for mixed organic pollutants.``

  1. Use of organoclays obtained with nonionic surfactants for drilling fluids base organic; O uso de argilas organofilicas obtidas com tensoativo nao-ionico para fluidos de perfuracao base organica

    Energy Technology Data Exchange (ETDEWEB)

    Sousa, F.K.A. [Universidade Federal de Campina Grande (UATEC/UFCG), PB (Brazil). Unidade Academica de Tecnologia do Desenvolvimento], e-mail: kegealves@ufcg.edu.br; Neves, G.A.; Ferreira, H.C.; Silva, A.L. [Universidade Federal de Campina Grande (UFCG/UAEMa), PB (Brazil). Unidade Academica de Engenharia de Materiais; Campos, L.F.A. [Departamento de Engenharia de Materiais, DEMat/CCT/UFPB, PB (Brazil)

    2010-07-01

    This paper aims to use the compositions of organo clays obtained with nonionic surfactant for drilling fluids organic base containing additives, emulsifiers, brine, activator, reducer filtered, adensante and evaluate their rheological, filtration and electrical stability. Were studied through the mixture delineament, ten compositions of organo clays, and its performance is evaluated by means of the rheological behavior (flow curves, GI, GF, VA, VP and LE) and the tests recommended by API (PE, EE and VF). The results were compared with the standard PETROBRAS and showed that among the developed compositions, two compositions showed promising that met most of the properties and use the clay of inferior quality (Bofe and Verde-lodo) in greater quantity and minimum clay Chocolate UBM, considered the best clay in the region mines Boa Vista, PB. (author)

  2. Optimization of compatible non-ionic surfactant for formulation development of hydrophobic conidia of entomopathogenic fungi, Beauveria bassiana (Hypocreales:Cordycipitaceae) and Metarhizium anisopliae Hypocreales:Clavicipita

    Science.gov (United States)

    Aerial conidia, especially dried conidia of entomopathogenic fungi, Beauveria bassiana and Metarhizium anisopliae are hydrophobic, and therefore surfactants are needed for developing water-based formulations in laboratory studies, greenhouse bioassays, and field trials as well as commercial product ...

  3. Study of nonionic surfactant aqueous two-phase extraction of amino acids%非离子表面活性剂双水相萃取氨基酸研究

    Institute of Scientific and Technical Information of China (English)

    孙晨; 刘广宇; 徐培辉

    2014-01-01

    This paper mainly researches on the phase behavior of the extraction distribution amino acid extract in nonionic surfactant in aqueous two-phase system. Extraction of L-phenylalanine with AEO-7/Na3PO4 aqueous two-phase,the effects of the content of AEO-7 and salt(NaCl,Na2SO4, Na3PO4),adding L-phenylalanine content of extracts,extraction time,extraction temperature were investigated. The results showed that the optimal conditions of AEO-7/Na3PO4,aqueous two-phase extraction of L-phenylalanine is volume concentration when AEO-7 was 8%,concentration of Na3PO4·12H2O for 85 g/L,temperature 40℃,concentration of L-phenylalanine is 0.532 8 g/L,time 60 min extraction of L-phenylalanine rate can reach 98.7%,the distribution coefficient of 15.3.%该文对氨基酸萃取液在非离子表面活性剂双水相体系中的萃取分配相行为进行研究。采用脂肪醇聚氧乙烯醚AEO-7/盐双水相萃取L-苯丙氨酸,考察了加盐(NaCl、Na2SO4、Na3PO4)、AEO-7含量、萃取时间、加入萃取物L-苯丙氨酸的含量以及萃取温度对双水相及萃取分离L-苯丙氨酸的影响。结果表明,AEO-7/Na3PO4双水相萃取L-苯丙氨酸的适宜条件是当AEO-7的体积浓度为8%,Na3PO4·12H2O的质量浓度为85 g/L,温度为40℃,L-苯丙氨酸的质量浓度为0.5328 g/L,时间为60 min时L-苯丙氨酸的萃取率可以达到98.7%,分配系数为15.3。

  4. Alcohols solubilization in a nonionic fluorinated surfactant based system: effects on the characteristics of mesoporous silica.

    Science.gov (United States)

    Blin, J L; Du, N; Stébé, M J

    2012-05-01

    In this study, we have used hydrogenated alcohols with different chain lengths and one fluorinated alcohol as additives to determine their effect on the characteristics of mesoporous materials prepared from fluorinated micelles.

  5. Structural studies of lamellar surfactant systems under shear

    DEFF Research Database (Denmark)

    Mortensen, K.

    2001-01-01

    Recent experimental studies on concentrated surfactant systems are reviewed. Particular attention is focused on the transformation from planar lamellar sheets to multilamellar vesicles. It is discussed whether both of these states are thermodynamic stable, or if the MLV is an artifact of shear...... induced factors. Recent studies includes the dependence on shear, and dependence on salt and cosurfactants, and thereby related lamellar defects. The review include moreover the demonstration that polymeric amphiphiles dramatically enhance the quality of classical surfactants. (C) 2001 Elsevier Science...

  6. Monitoring corrosion and corrosion control of iron in HCl by non-ionic surfactants of the TRITON-X series - Part II. Temperature effect, activation energies and thermodynamics of adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Amin, Mohammed A., E-mail: maaismail@yahoo.co [Materials and Corrosion Lab (MCL), Department of Chemistry, Faculty of Science, Taif University, 888 Hawiya (Saudi Arabia); Department of Chemistry, Faculty of Science, Ain shams University, 11566 Abbassia, Cairo (Egypt); Ahmed, M.A. [Physics Department, Faculty of Science, Taif University, 888 Hawiya (Saudi Arabia); Arida, H.A. [Materials and Corrosion Lab (MCL), Department of Chemistry, Faculty of Science, Taif University, 888 Hawiya (Saudi Arabia); Arslan, Taner [Department of Chemistry, Eskisehir Osmangazi University, 26480 Eskisehir (Turkey); Saracoglu, Murat [Faculty of Education, Erciyes University, 38039 Kayseri (Turkey); Kandemirli, Fatma [Department of Chemistry, Nigde University, 41000 Nigde (Turkey)

    2011-02-15

    Research highlights: TX-305 exhibits inhibiting properties for iron corrosion more than TX-165 and TX 100. Inhibition efficiency increases with temperature, suggesting chemical adsorption. The three tested surfactants act as mixed-type inhibitors with cathodic predominance. Validation of corrosion rates measured by Tafel extrapolation method is confirmed. - Abstract: The inhibition characteristics of non-ionic surfactants of the TRITON-X series, namely TRITON-X-100 (TX-100), TRITON-X-165 (TX-165) and TRITON-X-305 (TX-305), on the corrosion of iron was studied in 1.0 M HCl solutions as a function of inhibitor concentration (0.005-0.075 g L{sup -1}) and solution temperature (278-338 K). Measurements were conducted based on Tafel extrapolation method. Electrochemical frequency modulation (EFM), a non-destructive corrosion measurement technique that can directly give values of corrosion current without prior knowledge of Tafel constants, is also presented. Experimental corrosion rates determined by the Tafel extrapolation method were compared with corrosion rates obtained by the EFM technique and an independent method of chemical analysis. The chemical method of confirmation of the corrosion rates involved determination of the dissolved cation, using ICP-AES (inductively coupled plasma atomic emission spectrometry). The aim was to confirm validation of corrosion rates measured by the Tafel extrapolation method. Results obtained showed that, in all cases, the inhibition efficiency increased with increase in temperature, suggesting that chemical adsorption occurs. The adsorptive behaviour of the three surfactants followed Temkin-type isotherm. The standard free energies of adsorption decreased with temperature, reflecting better inhibition performance. These findings confirm chemisorption of the tested inhibitors. Thermodynamic activation functions of the dissolution process were also calculated as a function of each inhibitor concentration. All the results obtained from

  7. An investigation of bubble coalescence and post-rupture oscillation in non-ionic surfactant solutions using high-speed cinematography.

    Science.gov (United States)

    Bournival, G; Ata, S; Karakashev, S I; Jameson, G J

    2014-01-15

    Most processes involving bubbling in a liquid require small bubbles to maximise mass/energy transfer. A common method to prevent bubbles from coalescing is by the addition of surfactants. In order to get an insight into the coalescence process, capillary bubbles were observed using a high speed cinematography. Experiments were performed in solutions of 1-pentanol, 4-methyl-2-pentanol, tri(propylene glycol) methyl ether, and poly(propylene glycol) for which information such as the coalescence time and the deformation of the resultant bubble upon coalescence was extracted. It is shown in this study that the coalescence time increases with surfactant concentration until the appearance of a plateau. The increase in coalescence time with surfactant concentration could not be attributed only to surface elasticity. The oscillation of the resultant bubble was characterised by the damping of the oscillation. The results suggested that a minimum elasticity is required to achieve an increased damping and considerable diffusion has a detrimental effect on the dynamic response of the bubble, thereby reducing the damping.

  8. Surfactant enhanced volumetric sweep efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, J.H.; Scamehorn, J.F.

    1989-10-01

    Surfactant-enhanced waterflooding is a novel EOR method aimed to improve the volumetric sweep efficiencies in reservoirs. The technique depends upon the ability to induce phase changes in surfactant solutions by mixing with surfactants of opposite charge or with salts of appropriate type. One surfactant or salt solution is injected into the reservoir. It is followed later by injection of another surfactant or salt solution. The sequence of injections is arranged so that the two solutions do not mix until they are into the permeable regions well away from the well bore. When they mix at this point, by design they form a precipitate or gel-like coacervate phase, plugging this permeable region, forcing flow through less permeable regions of the reservoir, improving sweep efficiency. The selectivity of the plugging process is demonstrated by achieving permeability reductions in the high permeable regions of Berea sandstone cores. Strategies were set to obtain a better control over the plug placement and the stability of plugs. A numerical simulator has been developed to investigate the potential increases in oil production of model systems. Furthermore, the hardness tolerance of anionic surfactant solutions is shown to be enhanced by addition of monovalent electrolyte or nonionic surfactants. 34 refs., 32 figs., 8 tabs.

  9. NIOSOMES: A ROLE IN TARGETED DRUG DELIVERY SYSTEM

    Directory of Open Access Journals (Sweden)

    Soumya Singh

    2013-02-01

    Full Text Available Niosomes are non-ionic surfactant vesicles inclosing an aqueous phase and a wide range of molecules could be encapsulated within aqueous spaces of lipid membrane vesicles. They are microscopic lamellar structures formed on the admixture of a non-ionic surfactant, cholesterol and phosphate with subsequent hydration in aqueous media. Niosomes belongs to novel drug delivery system which offers a large number of advantages over other conventional and vesicular delivery systems. Namely they are the targeted drug delivery system which showing reduction of dose, stability and compatibility of non-ionic surfactants, easy modification, delayed clearance, suitability for a wide range of Active Pharmaceutical Agents.

  10. Growth Mechanism of Gold Nanorods in Binary Surfactant System

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bo-Mi; Seo, Sun-Hwa; Joe, Ara; Shim, Kyu-Dong; Jang, Eue-Soon [Kumoh National Institute of Technology, Gumi (Korea, Republic of)

    2016-06-15

    In order to reveal the growth mechanism of gold nanorods (GNRs) in a binary surfactant system, we synthesized various GNRs by changing the concentration of the surfactants, AgNO{sub 3}, and HBr in the growth solution. We found that the benzyldime thylhexadecylammoniumchloride surfactant had weak interaction with the gold ions, but it could reduce the membrane fluidity. In addition, we could dramatically decrease the cetyltrimethylammonium bromide concentration required for GNR growth by adding an HBr solution. Notably, Ag{sup +} ions were necessary to break the symmetry of the seed crystals for GNR growth, but increasing the concentration of Ag{sup +} and Br{sup -} ions caused a decrease in the template size.

  11. 曝气强化非离子表面活性剂洗涤法修复柴油污染土壤%Remediation of diesel-contaminated soil by aeration enhanced washing with nonionic surfactant

    Institute of Scientific and Technical Information of China (English)

    汤志涛; 陈泉源

    2016-01-01

    The diesel-contaminated soil was remediated by ex-situ aeration enhanced washing method with nonionic surfactant. The factors affecting the washing effect were investigated,and the washing mechanism was studied by determination of surface tension and contact angle. The experimental results show that:The washing effect of diesel oil from diesel-contaminated soil can be enhanced by aeration and the removal rate of diesel oil is increased by 10%-20%;The order of washing effect by 3 kinds of nonionic surfactants is Brij-35>TX-100>Tw-80;Under the optimum conditions of Brij-35 concentration one time of CMC,aeration rate 7.5 L/min,washing time 60 mine and washing solution pH 11.0,the removal rate of diesel oil is 77.4%,the oil content of the diesel-contaminated soil is decreased from 7.0%to 1.6%,the contact angle is decreased from 24.12° to 6.65°,and the hydrophily of the soil can be recovered after washing;The surface tension of the washing solution is decreased with the increase of surfactant concentration,but not affected by washing solution pH.%采用异位修复法,利用非离子表面活性剂洗涤柴油污染土壤,并在洗涤过程中曝气强化。考察了洗涤效果的影响因素,并通过表面张力和接触角的测定探讨了洗涤机理。实验结果表明:曝气对污染土壤中柴油的洗脱有强化作用,可提高洗脱率10%~20%;3种非离子表面活性剂的洗脱效果优劣次序为聚氧乙烯月桂醚(Brij-35)>曲拉通X-100(TX-100)>吐温-80(Tw-80);在表面活性剂浓度为1倍临界胶束浓度、曝气量为7.5 L/min、洗涤时间为60 min、洗涤液pH为11.0的优化条件下,Brij-35对柴油的洗脱率达77.4%,污染土样的含油率从7.0%降至1.6%,接触角从24.12°降至6.65°,可基本恢复土壤的亲水性;洗涤液的表面张力随表面活性剂浓度的增加而降低,但不受洗涤液pH的影响。

  12. Study on interfacial tension of mimetic oil and water system with blend surfactants%复配表面活性剂-模拟油-水体系的界面张力研究

    Institute of Scientific and Technical Information of China (English)

    刘宣池; 张亚刚; 于二雷; 崔平正; 吾满江·艾力

    2016-01-01

    在45℃下测定了不同类型表面活性剂(阴离子、阳离子和非离子表面活性剂以及高分子双子表面活性剂、非对称两性双子表面活性剂)与煤油-水体系的界面张力,发现非离子表面活性剂效果最好,界面张力可达0.690 mN/m。采用聚乙二醇辛基苯基醚与其他类型的表面活性剂进行两两复配,考察复配表面活性剂的种类、质量比、总质量浓度对模拟油-水体系界面张力的影响。发现聚乙二醇辛基苯基醚与非对称两性双子表面活性剂C15 EC-S-C16以质量比7∶3进行复配,总质量浓度为50 g/L时,界面张力达到0.024 mN/m。%Interfacial tension of kerosene-water system with different types of surfactant (anionic,cationic and nonionic surfactant as well as polymeric Gemini surfactant and asymmetric amphoteric Gemini surfactants)was investigated and compared. Results showed that nonionic surfactant is the one which may display lowest interfacial tension of 0.690 mN/m. Ethoxylated octylphenol nonionic surfactant (OP type)was selected to be blended with different types of other surfactants to examine the effects of type of the blend surfactant and their mass ratio,as well as the overall mass concentration on the interfacial tension of the mimetic oil - water system. Results showed the blend surfactant composed of ethoxylated octylphenol and asymmetric amphoteric Gemini surfactant (C15 EC-S-C16 ,laboratory prepared)with mass ratio of 7∶3 and overall mass concentration of 50 g/L can reduce the interfacial tension to a minimum value of 0.024 mN/m.

  13. Circulating surfactant protein D is decreased in systemic lupus erythematosus

    DEFF Research Database (Denmark)

    Hoegh, Silje Vermedal; Voss, Anne; Sorensen, Grith Lykke

    2009-01-01

    Objective. Deficiencies of innate immune molecules like mannan binding lectin (MBL) have been implicated in the pathogenesis of systemic lupus erythematosus (SLE). Surfactant protein D (SP-D) and MBL belong to the same family of innate immune molecules - the collectins, which share important...

  14. Phase behavior and oil recovery investigations using mixed and alkaline-enhanced surfactant systems

    Energy Technology Data Exchange (ETDEWEB)

    Llave, F.M.; Gall, B.L.; French, T.R.; Noll, L.A.; Munden, S.A.

    1992-03-01

    The results of an evaluation of different mixed surfactant and alkaline-enhanced surfactant systems for enhanced oil recovery are described. Several mixed surfactant systems have been studies to evaluate their oil recovery potential as well as improved adaptability to different ranges of salinity, divalent ion concentrations, and temperature. Several combinations of screening methods were used to help identify potential chemical formulations and determine conditions where particular chemical systems can be applied. The effects of different parameters on the behavior of the overall surfactant system were also studied. Several commercially available surfactants were tested as primary components in the mixtures used in the study. These surfactants were formulated with different secondary as well as tertiary components, including ethoxylated and non-ethoxylated sulfonates and sulfates. Improved salinity and hardness tolerance was achieved for some of these chemical systems. The salinity tolerance of these systems were found to be dependent on the molecular weight, surfactant type, and concentration of the surfactant components.

  15. Viscosity of the oil-in-water Pickering emulsion stabilized by surfactant-polymer and nanoparticle-surfactant-polymer system

    Science.gov (United States)

    Sharma, Tushar; Kumar, G. Suresh; Chon, Bo Hyun; Sangwai, Jitendra S.

    2014-11-01

    Information on the viscosity of Pickering emulsion is required for their successful application in upstream oil and gas industry to understand their stability at extreme environment. In this work, a novel formulation of oil-in-water (o/w) Pickering emulsion stabilized using nanoparticle-surfactant-polymer (polyacrylamide) system as formulated in our earlier work (Sharma et al., Journal of Industrial and Engineering Chemistry, 2014) is investigated for rheological stability at high pressure and high temperature (HPHT) conditions using a controlled-strain rheometer. The nanoparticle (SiO2 and clay) concentration is varied from 1.0 to 5.0 wt%. The results are compared with the rheological behavior of simple o/w emulsion stabilized by surfactant-polymer system. Both the emulsions exhibit non-Newtonian shear thinning behavior. A positive shift in this behavior is observed for surfactant-polymer stabilized emulsion at high pressure conditions. Yield stress is observed to increase with pressure for surfactant-polymer emulsion. In addition, increase in temperature has an adverse effect on the viscosity of emulsion stabilized by surfactant-polymer system. In case of nanoparticle-surfactant-polymer stabilized o/w emulsion system, the viscosity and yield stress are predominantly constant for varying pressure and temperature conditions. The viscosity data for both o/w emulsion systems are fitted by the Herschel-Bulkley model and found to be satisfactory. In general, the study indicates that the Pickering emulsion stabilized by nanoparticle-surfactant-polymer system shows improved and stable rheological properties as compared to conventional emulsion stabilized by surfactant-polymer system indicating their successful application for HPHT environment in upstream oil and gas industry.

  16. Structure and Conformational Dynamics of DMPC/Dicationic Surfactant and DMPC/Dicationic Surfactant/DNA Systems

    Directory of Open Access Journals (Sweden)

    Maciej Kozak

    2013-04-01

    Full Text Available Amphiphilic dicationic surfactants, known as gemini surfactants, are currently studied for gene delivery purposes. The gemini surfactant molecule is composed of two hydrophilic “head” groups attached to hydrophobic chains and connected via molecular linker between them. The influence of different concentrations of 1,5-bis (1-imidazolilo-3-decyloxymethyl pentane chloride (gemini surfactant on the thermotropic phase behaviour of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC bilayers with and without the presence of DNA was investigated using Fourier transformed infrared (FTIR and circular dichroism (CD spectroscopies, small angle scattering of synchrotron radiation and differential scanning calorimetry. With increasing concentration of surfactant in DMPC/DNA systems, a disappearance of pretransition and a decrease in the main phase transition enthalpy and temperature were observed. The increasing intensity of diffraction peaks as a function of surfactant concentration also clearly shows the ability of the surfactant to promote the organisation of lipid bilayers in the multilayer lamellar phase.

  17. Microcalorimetric investigation of the effect of non-ionic surfactant on biodegradation of pyrene by PAH-degrading bacteria Burkholderia cepacia.

    Science.gov (United States)

    Chen, Ke; Zhu, Qing; Qian, Yiguang; Song, Ying; Yao, Jun; Choi, Martin M F

    2013-12-01

    Polycyclic aromatic hydrocarbons (PAHs) are widespread in various ecosystems and are pollutants of great concern due to their potential toxicity, mutagenecity and carcinogenicity. Surfactant has become a hot topic for its wide application in the bioremediation of PAHs. The aim of this work is to explore a microcalorimetric method to determine the toxic effect of pyrene on Bacillus subtilis (B. subtilis) and the PAH-degrading bacteria Burkholderia cepacia (B. cepacia) and to evaluate the effect of Tween 80 on biodegradation of pyrene. Power-time curves were studied and calorimetric parameters including the growth rate constant (k), half inhibitory concentration (IC₅₀), and total thermal effect (Q(T)) were determined. B. subtilis, B. cepacia and B. cepacia with Tween 80 were completely inhibited when the concentration of pyrene were 200, 800 and 1600 µg mL⁻¹, respectively. B. cepacia shows better tolerance to pyrene than B. subtilis. Tween 80 significantly improves the biodegradation of pyrene by increasing the bioavailability of pyrene. In addition, the expression of catechol 2,3-dioxygenase (C23O) in B. cepacia is responsible for the degradation of pyrene and plays an important role in improving the biodegradation of pyrene. Moreover, the activity of C23O increases with the application of Tween 80. The enhanced bioavailability and biodegradation of pyrene by Tween 80 shows the potential use of Tween 80 in the PAHs bioremediation.

  18. Extraction of monoclonal antibodies (IgG1) using anionic and anionic/nonionic reverse micelles.

    Science.gov (United States)

    George, Daliya A; Stuckey, David C

    2010-01-01

    Purification schemes for antibody production based on affinity chromatography are trying to keep pace with increases in cell culture expression levels and many current research initiatives are focused on finding alternatives to chromatography for the purification of Monoclonal antibodies (MAbs). In this article, we have investigated an alternative separation technique based on liquid-liquid extraction called the reverse micellar extraction. We extracted MAb (IgG1) using reverse micelles of an anionic surfactant, sodium bis 2-ethyl-hexyl sulfosuccinate (AOT) and a combination of anionic (AOT) and nonionic surfactants (Brij-30, Tween-85, Span-85) using isooctane as the solvent system. The extraction efficiency of IgG1 was studied by varying parameters, such as pH of the aqueous phase, cation concentration, and type and surfactant concentration. Using the AOT/Isooctane reverse micellar system, we could achieve good overall extraction of IgG1 (between 80 and 90%), but only 30% of the bioactivity of IgG1 could be recovered at the end of the extraction by using its binding to affinity chromatography columns as a surrogate measure of activity. As anionic surfactants were suspected as being one of the reasons for the reduced activity, we decided to combine a nonionic surfactant with an anionic surfactant and then study its effect on the extraction efficiency and bioactivity. The best results were obtained using an AOT/Brij-30/Isooctane reverse micellar system, which gave an overall extraction above 90 and 59% overall activity recovery. An AOT/Tween-85/Isooctane reverse micellar system gave an overall extraction of between 75 and 80% and overall activity recovery of around 40-45%. The results showed that the activity recovery of IgG1 can be significantly enhanced using different surfactant combination systems, and if the recovery of IgG1 can be further enhanced, the technique shows considerable promise for the downstream purification of MAbs.

  19. Use of surfactants for the remediation of contaminated soils: a review.

    Science.gov (United States)

    Mao, Xuhui; Jiang, Rui; Xiao, Wei; Yu, Jiaguo

    2015-03-21

    Due to the great harm caused by soil contamination, there is an increasing interest to apply surfactants to the remediation of a variety of contaminated soils worldwide. This review article summarizes the findings of recent literatures regarding remediation of contaminated soils/sites using surfactants as an enhancing agent. For the surfactant-based remedial technologies, the adsorption behaviors of surfactants onto soil, the solubilizing capability of surfactants, and the toxicity and biocompatibility of surfactants are important considerations. Surfactants can enhance desorption of pollutants from soil, and promote bioremediation of organics by increasing bioavailability of pollutants. The removal of heavy metals and radionuclides from soils involves the mechanisms of dissolution, surfactant-associated complexation, and ionic exchange. In addition to the conventional ionic and nonionic surfactants, gemini surfactants and biosurfactants are also applied to soil remediation due to their benign features like lower critical micelle concentration (CMC) values and better biocompatibility. Mixed surfactant systems and combined use of surfactants with other additives are often adopted to improve the overall performance of soil washing solution for decontamination. Worldwide the field studies and full-scale remediation using surfactant-based technologies are yet limited, however, the already known cases reveal the good prospect of applying surfactant-based technologies to soil remediation.

  20. Influence of water concentrations on the phase transformation of a model surfactant/co-surfactant/water system

    Science.gov (United States)

    Lunkad, Raju; Srivastava, Arpita; Debnath, Ananya

    2017-02-01

    The influence of water concentrations on phase transformations of a surfactant/co-surfactant/water system is investigated by using all atom molecular dynamics simulations. At higher water concentrations, where surfactant (behenyl trimethyl ammonium chloride, BTMAC) to co-surfactant (stearyl alcohol, SA) ratio is fixed, BTMAC and SA self-assemble into spherical micelles, which transform into strongly interdigitated one dimensional rippled lamellar phases upon decreasing water concentrations. Fragmentation or fusions of spherical micelles of different sizes are evident from the radial distribution functions at different temperatures. However, at lower water concentrations rippled lamellar phase transforms into an LβI phase upon heating. Our simulations reveal that the concentrations of water can influence available space around the head groups which couple with critical thickness to accommodate the packing fraction required for respective phases. This directs towards obtaining a controlling factor to design desired phases important for industrial and medical applications in the future.

  1. Rheology of cellulose nanofibrils in the presence of surfactants.

    Science.gov (United States)

    Quennouz, Nawal; Hashmi, Sara M; Choi, Hong Sung; Kim, Jin Woong; Osuji, Chinedum O

    2016-01-07

    Cellulose nanofibrils (CNFs) present unique opportunities for rheology modification in complex fluids. Here we systematically consider the effect of ionic and non-ionic surfactants on the rheology of dilute CNF suspensions. Neat suspensions are transparent yield-stress fluids which display strong shear thinning and power-law dependence of modulus on concentration, G' ∼ c(2.1). Surfactant addition below a critical mass concentration cc produces an increase in the gel modulus with retention of optical clarity. Larger than critical concentrations induce significant fibril aggregation leading to the loss of suspension stability and optical clarity, and to aggregate sedimentation. The critical concentration was the lowest for a cationic surfactant (DTAB), cc ≈ 0.08%, while suspension stability was retained for non-ionic surfactants (Pluronic F68, TX100) at concentrations up to 8%. The anionic surfactant SDS led to a loss of stability at cc ≈ 1.6% whereas suspension stability was not compromised by anionic SLES up to 8%. Dynamic light scattering data are consistent with a scenario in which gel formation is driven by micelle-nanofibril bridging mediated by associative interactions of ethoxylated surfactant headgroups with the cellulose fibrils. This may explain the strong difference between the properties of SDS and SLES-modified suspensions. These results have implications for the use of CNFs as a rheology modifier in surfactant-containing systems.

  2. Biphasic Catalytic(Hydroformylation of 1-Dodecene in Micellar System with Cationic Gemini Surfactants

    Institute of Scientific and Technical Information of China (English)

    Min LI; Bin XU; Hua CHEN; Hong Jie ZHENG; Xue Yuan HUANG; Yao Zhong LI; Xian Jun LI

    2004-01-01

    The promotion effect of cationic gemini surfactants for the hydroformylation of 1-dodecene in the organic/aqueous biphasic catalytic system is reported. The hydroformylation reaction in the presence of gemini surfactant occurred with higher turnover frequency and higher selectivity for linear aldehyde than using conventional monomeric surfactant CTAB.

  3. Characterization and optical properties of nano-ceria synthesized by surfactant-mediated precipitation technique in mixed solvent system

    Energy Technology Data Exchange (ETDEWEB)

    Sujana, M.G. [Institute of Minerals and Materials Technology, (Formerly RRL), Bhubaneswar, Orissa (India)], E-mail: mgsujana@gmail.com; Chattopadyay, K.K. [Department of Physics, Jadavpur University, Kolkata (India); Anand, S. [Institute of Minerals and Materials Technology, (Formerly RRL), Bhubaneswar, Orissa (India)

    2008-09-15

    Crystalline cerium oxide nanoparticles have been synthesized by surfactant-mediated precipitation technique in acetone/water mixed solvent system. The cerium nitrate hexahydrate as precursor and non-ionic surfactant Tween 80 were taken in acetone/water system and precipitated with ammonia at pH 10. The sample was then calcined for 2 h in the temperature range of 200-800 deg. C and characterized by X-ray diffraction (XRD), FTIR, BET surface area and TEM. It was found from XRD studies that the crystallite size increased with calcination temperature from 3 nm to 13 nm and the surface area was found to be 133 m{sup 2}/g for 400 deg. C calcined sample. The particle size obtained from high-resolution transmission electron microscope (HRTEM) was in the range of 4.5 nm with uniform shape and narrow particle size distribution. The diffraction pattern completely indexed with the cubic fluorite structure of CeO{sub 2}. The calcined cerium oxide nanoparticles showed strong UV absorption and room temperature photoluminescence (PL)

  4. Characterization and optical properties of nano-ceria synthesized by surfactant-mediated precipitation technique in mixed solvent system

    Science.gov (United States)

    Sujana, M. G.; Chattopadyay, K. K.; Anand, S.

    2008-09-01

    Crystalline cerium oxide nanoparticles have been synthesized by surfactant-mediated precipitation technique in acetone/water mixed solvent system. The cerium nitrate hexahydrate as precursor and non-ionic surfactant Tween 80 were taken in acetone/water system and precipitated with ammonia at pH 10. The sample was then calcined for 2 h in the temperature range of 200-800 °C and characterized by X-ray diffraction (XRD), FTIR, BET surface area and TEM. It was found from XRD studies that the crystallite size increased with calcination temperature from 3 nm to 13 nm and the surface area was found to be 133 m 2/g for 400 °C calcined sample. The particle size obtained from high-resolution transmission electron microscope (HRTEM) was in the range of 4.5 nm with uniform shape and narrow particle size distribution. The diffraction pattern completely indexed with the cubic fluorite structure of CeO 2. The calcined cerium oxide nanoparticles showed strong UV absorption and room temperature photoluminescence (PL).

  5. Synthesis of mesoporous MCM-48 with a mixed non ionic-cationic surfactant templating pathway

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In a hydrothermal system, we studied the influence of nonionic surfactant poly(ethylenglycol) monooctylphenyl ether (OP-10) on the self-assembling process of mesoporous molecular sieve MCM-48 and found that OP-10 can decrease the amount of cationic surfactant needed for the preparation of MCM-48 further by its stronger van der Waals force , shorten the synthetic period and produce MCM-48 with more extensive cross-linked framework. By altering the ratio of nonionic surfactant to cationic surfactant, we could obtain the mesoporous molecular sieves with different structures. When the crystallization temperature exceeded-140℃, OP-10 would separate from miceHe, lose its amphiphilic character, and then hamper the conversion of lamellar mesoporous molecular sieves into microporous materials.

  6. Development of PNA-Surfactant Systems for Nucleic Acid Separations

    Science.gov (United States)

    Vernille, James; Armitage, Bruce; Schneider, James

    2002-03-01

    We have been exploring the use of novel peptide nucleic acid (PNA) surfactants for use in sequence specific, scalable DNA separations. While the synthetic and physical characteristics of PNA make it a useful molecule for bioseparations, PNA shows limited water solubility. Here we describe a molecular design strategy to improve water solubility while maintaining sequence specificity. A candidate molecule has been identified which contains lysine residues and a short alkane tail. Melting temperature data show that lipid tail interactions with the DNA nucleobases have a small but significant effect on stability while the added lysines stabilize the complex in an ionic strength dependent way. We also discuss the incorporation of these surfactants into micellar systems for novel separations.

  7. Critical interaction strength for surfactant-induced mesomorphic structures in polymer-surfactant systems

    NARCIS (Netherlands)

    Ruokolainen, J.; Torkkeli, M.; Serimaa, R.; Vahvaselka, S.; Saariaho, M.; ten Brinke, G.; Ikkala, O.; Vahvaselkä, Sakari

    1996-01-01

    The critical interaction strength to induce mesomorphic structures in flexible polymers by complexing with surfactants is determined by using surfactants with different hydrogen-bonding strengths;. Two essential requirements have to be satisfied: (i) the association has to be strong enough, otherwis

  8. An intensive dispersion and synchronous assembly of single-walled carbon nanotubes in a surfactant-oil-water association system.

    Science.gov (United States)

    Zhang, Yan; Li, Dechun; Wu, Lin; Zhou, Liang; Du, Yanan; Wang, Meng; Li, Ying

    2016-04-28

    This paper reports a novel approach for achieving an intensive dispersion and synchronous assembly of single-walled carbon nanotubes (SWNTs) using a surfactant-oil-water association system as medium. A kind of nonionic surfactant N,N-bis(2-hydroxyethyl)dodecanamide (DDA) which could form a bi-continuous network structure not only in water but also in dodecane was used. The SWNTs were infiltrated into the dodecane-DDA mixture instead of DDA aqueous solution, and the attractive van der Waals forces between the pristine SWNT agglomerates were decreased in the first place; the thorough dispersion of the SWNTs was completed in the subsequent phase transformation by adjusting the oil/water ratio, along with mild sonication stirring. The individual SWNTs with different chiralities, such as (6,5), (7,5), (7,6), and (9,4), are all separated well after mild centrifugation treatment, which was confirmed by the well-resolved UV-Vis-NIR absorption and sharp fluorescence spectra. In particular, the self-assembly of DDA drove the separated individual SWNTs forming a large scale spatial network architecture. We believe that the SOW-SWNT suspension has high potential in constructing new functional materials by introducing diverse desirable components through the oil phase and also the water phase medium.

  9. Genotoxicity induced by saponified coconut oil surfactant in prokaryote systems.

    Science.gov (United States)

    Petta, Tirzah Braz; de Medeiros, Sílvia Regina Batistuzzo; do Egito, Eryvaldo Sócrates Tabosa; Agnez-Lima, Lucymara Fassarella

    2004-11-01

    Surfactants are amphiphilic substances with special properties and chemical structures that allow a reduction in interfacial tension, which permits an increase in molecule solubilization. The critical micelle concentration (CMC) is an important characteristic of surfactants that determines their aggregate state, which is generally related to its functional mechanism. In this work the genotoxic potential of saponified coconut oil (SCO), a surfactant obtained from Cocos nucifera, was analyzed using prokaryote systems. DNA strand breaks were not observed after treatment of a plasmid with SCO. Negative results were also obtained in the SOS Chromotest using Escherichia coli strains PQ35 and PQ37. A moderate toxicity of SCO was observed after treatment of strain CC104 with a concentration above its CMC, in which micelles were found. Nevertheless, this treatment was not cytotoxic to a CC104mutMmutY strain. Furthermore, in this DNA repair-deficient strain treatment with a SCO dose below its CMC, in which only monomers were found, demonstrated the possibility of an antioxidant effect, since a reduction in spontaneous mutagenesis frequency was observed. Finally, in an Ames test without metabolic activation mutagenicity induction was observed in strains TA100 and TA104 with treatment doses below the CMC. The cytotoxic, antioxidant and mutagenic effects of SCO can be influenced by the aggregational state.

  10. Mechanisms for lowering of interfacial tension in alkali/acidic oil systems; Effect of added surfactant

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, J. Wasan, D.T. (Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Chemical Engineering)

    1992-08-01

    This paper reports that experimental studies are conducted in order to determine the physicochemical mechanism responsible for lowering of interfacial tension in alkali, surfactant, and surfactant-enhanced alkali/acidic oil systems. A well-defined model oil is chosen to examine the influence of various surfactants and surfactant mixtures, such as oleic acid and its ionic counterpart, sodium dodecyl sulfate, petroleum sulfonate, and isobutanol, on equilibrium interfacial tension. With added surfactant alone, the interfacial tension goes through an ultralow minimum with increasing acid concentration. This proves for the first time that the un-ionized acid species plays a major role in affecting interfacial tension, and the ionized acid species.

  11. Studies of the behaviour of alcohols as co-surfactants in stabilizing microemulsions

    Energy Technology Data Exchange (ETDEWEB)

    Bahadur, P. (Chemistry Dept., D.A.V. (P.G.) Coll., Muzaffarnagar- (India)); Chand, M. (Chemistry Dept., D.A.V. (P.G.) Coll., Muzaffarnagar- (India))

    Micoremulsion formation was investigated in the following quaternary systems. Water/oil/surfactant/co-surfactant alcohol systems i.e. (i) water/xylene, benzene, toluene/tween-20/propanol-1, propanol-2, methanol, (ii) water/xylene, benzene, toluene/sodium dodecyl benzene sulphonate/propanol-1, propanol-2, methanol, (iii) water/xylene, benzene, toluene/dodecyl ammonium chloride/propanol-1, propanol-2, methanol. The formation of microemulsions is explained in terms of ternary phase diagrams for all three nonionic, anionic and cationic surfactants used. The viscosities and densities of the microemulsions were determined in all the systems. (orig.)

  12. Immobilization of enzymes using non-ionic colloidal liquid aphrons (CLAs): Surface and enzyme effects.

    Science.gov (United States)

    Ward, Keeran; Xi, Jingshu; Stuckey, David C

    2015-12-01

    The use of non-ionic colloidal liquid aphrons (CLAs) as a support for enzyme immobilisation was investigated. Formulation required the mixing of an aqueous-surfactant solution with a relatively non-polar solvent-surfactant solution, forming a solvent droplet surrounded by a thin stabilised aqueous film (soapy shell). Studies utilising anionic surfactants have showed increased retention, however, very little have been understood about the forces governing immobilisation. This study seeks to determine the effects of enzyme properties on CLA immobilisation by examining a non-ionic/non-polar solvent system comprised of two non-ionic surfactants, Tween 20 and 80, mineral oil and the enzymes lipase, aprotinin and α-chymotrypsin. From these results it was deduced that hydrophobic interactions strongly governed immobilisation. Confocal Scanning Laser Microscopy (CSLM) revealed that immobilisation was predominantly achieved by surface adsorption attributed to hydrophobic interactions between the enzyme and the CLA surface. Enzyme surface affinity was found to increase when added directly to the formulation (pre-manufacture addition), as opposed to the bulk continuous phase (post-manufacture addition), with α-chymotrypsin and aprotinin being the most perturbed, while lipase was relatively unaffected. The effect of zeta potential on immobilisation showed that enzymes adsorbed better closer to their pI, indicating that charge minimisation was necessary for immobilisation. Finally, the effect of increasing enzyme concentration in the aqueous phase resulted in an increase in adsorption for all enzymes due to cooperativity between protein molecules, with saturation occurring faster at higher adsorption rates.

  13. Effect of Exposure to Non-ionizing Radiation (Electromagnetic Fields on Human System: A Literature Review

    Directory of Open Access Journals (Sweden)

    Paula Rubya Souza C and acirc;mara

    2014-08-01

    Full Text Available The indiscriminate presence of radio base stations, which emit non-ionizing radiation (NIR, as well as the frequent use of mobile phones, can cause increased susceptibility of populations to the emergence of diseases such as cancers of the head and neck, biochemical, hematopoietic and hepatic changes, among others. Exposure to physical contamination, including NIR, has been implicated in numerous diseases, raising concerns about the widespread sources of exposure to this type of radiation. This paper reviews studies that have assessed associations between likely exposure to electromagnetic fields, such as radiofrequency transmissions, and many kinds of human diseases including cancer, as well as alerts to the current knowledge on the association between environmental exposure to NIR and the risk of development of adverse human health effects. This way, there appears to be an urgent need to reconsider exposure limits for low frequency and static magnetic fields, based on combined experimental and epidemiological research. [J Interdiscipl Histopathol 2014; 2(4.000: 187-190

  14. Use of surfactants for the remediation of contaminated soils: A review

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Xuhui, E-mail: clab@whu.edu.cn [School of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Jiang, Rui; Xiao, Wei [School of Resource and Environmental Science, Wuhan University, Wuhan 430072 (China); Yu, Jiaguo, E-mail: jiaguoyu@yahoo.com [State Key Laboratory of Advanced Technology for Material Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China)

    2015-03-21

    Highlights: • The recent advances in use of surfactant for soil remediation are reviewed. • The mechanisms of surfactant-based soil remediation are discussed. • A review on the application of different types of surfactants is made. • The future research direction of surfactant-based technologies is suggested. - Abstract: Due to the great harm caused by soil contamination, there is an increasing interest to apply surfactants to the remediation of a variety of contaminated soils worldwide. This review article summarizes the findings of recent literatures regarding remediation of contaminated soils/sites using surfactants as an enhancing agent. For the surfactant-based remedial technologies, the adsorption behaviors of surfactants onto soil, the solubilizing capability of surfactants, and the toxicity and biocompatibility of surfactants are important considerations. Surfactants can enhance desorption of pollutants from soil, and promote bioremediation of organics by increasing bioavailability of pollutants. The removal of heavy metals and radionuclides from soils involves the mechanisms of dissolution, surfactant-associated complexation, and ionic exchange. In addition to the conventional ionic and nonionic surfactants, gemini surfactants and biosurfactants are also applied to soil remediation due to their benign features like lower critical micelle concentration (CMC) values and better biocompatibility. Mixed surfactant systems and combined use of surfactants with other additives are often adopted to improve the overall performance of soil washing solution for decontamination. Worldwide the field studies and full-scale remediation using surfactant-based technologies are yet limited, however, the already known cases reveal the good prospect of applying surfactant-based technologies to soil remediation.

  15. 阴离子/非离子表面活性剂体系洗涤含油污泥%Experiment on enhanced washing of oily sludge by anionic/nonionic mixed surfactant

    Institute of Scientific and Technical Information of China (English)

    刁潘; 刘静; 张永奎; 刘瑾; 姚太平

    2014-01-01

    Preparation of complex detergent and experiments for the optimization of washing condition were conducted by treating the heavily oil-contaminated soil from an oilfield in Xinjiang. Orthogonal experiments were carried out to investigate the influence of concentrations of anionic surfactant, nonionic surfactant and the assistant washing agents (sodium silicate) on the residual oil content in the sample. It was found that there was a strong interaction between LAS and APEO,which enhanced washing effect and reduced the amount of detergent. The best detergent formulations were:sodium dodecyl benzene sulfonate (LAS) 2g/L,alkyl phenol ethoxylates (APEO) 3g/L,Na2SiO3 3g/L. The optimal liquid-solid ratio,temperature and washing time were 10∶1,70℃ and 1h. The oil content in sludge sample reduced from 26.07% to 1.21% by washing. The components removed by washing were analyzed by infrared spectroscopy (IR). It showed that most saturates,aromatics,resin, asphaltene in oily sludge were removed,which were considered as four main components in oil. Especially,saturates were removed obviously.%针对新疆某油田重度石油污染土壤,进行了洗涤剂的复配及洗脱条件的优化研究。考察了阴离子表面活性剂浓度、非离子表面活性剂浓度以及硅酸钠助剂浓度对残油量的影响。正交实验结果表明,十二烷基苯磺酸钠(LAS)与烷基酚聚氧乙烯醚(平平加,APEO)间存在着较强的交互协同作用;两者复配可以增强洗涤效果,并减少药剂用量。优化的复配洗涤剂配方为: LAS 2g/L,平平加3g/L,Na2SiO33g/L。复配洗涤剂洗涤含油污泥的最佳操作条件为:液固质量比10∶1、洗涤温度70℃、洗涤时间1h,在此条件下污泥含油量从26.07%降低至1.21%。对污泥洗涤前后的红外光谱检测表明该复配洗涤剂对于污泥中原油的饱和分、芳香分、胶质和沥青质都有洗涤效果,特别是对饱和分的去除效果尤为显著。

  16. Anaerobic digestion of aircraft deicing fluid wastes: interactions and toxicity of corrosion inhibitors and surfactants.

    Science.gov (United States)

    Gruden, Cyndee L; Hernandez, Mark

    2002-01-01

    Corrosion inhibitors and surfactants are present in aircraft deicing fluids (ADFs) at significant concentrations (> 1% w/w). The purpose of this research was to study the interactions of a common nonionic surfactant with the commercially significant corrosion inhibitors used in modern ADF (4- and 5-methylbenzotriazole [MeBT]), and to determine the effects of their mixture on the conventional anaerobic digestion process. In mesophilic anaerobic microcosms codigesting wastewater solids, propylene glycol, and MeBT, increasing surfactant levels resulted in enhanced MeBT sorption on digester solids. As judged by anaerobic toxicity assays, responses from digesters containing surfactant concentrations below their critical micelle concentration (CMC) suggested that low nonionic surfactant concentrations could facilitate a reduction in the apparent toxicity of MeBT. In microcosms exposed to surfactant concentrations above their CMC, no increase in MeBT solubility was observed, and the anaerobic toxicity response corresponded to control systems not containing surfactant. Direct microscopic measurements of digesting biomass using fluorescent phylogenetic probes (fluorescent in situ hybridization) revealed that members of the domain Bacteria were more sensitive to MeBT in the presence of surfactant than were members of the domain Archaea.

  17. Crystalline fibrillar gel formation in aqueous surfactant-antioxidant system.

    Science.gov (United States)

    Joseph, Linet Rose; Tata, B V R; Sreejith, Lisa

    2015-08-01

    Cetyltrimethylammonium bromide (CTAB) is a well-known cationic surfactant capable to micellize into diverse morphologies in aqueous medium. We observed the formation of an opaque gel state from aqueous CTAB solution in the presence of the aromatic additive, para-coumaric acid (PCA). Optical microscopic images revealed the presence of large fibrils in the system at room temperature. Gel nature of the fibrils was confirmed by rheological measurements. Presence of interstitial water in the fibrils was recognized with Raman spectroscopy. On heating the sample above 30 (°) C, the fibrillar gel state changes to a transparent liquid state with Newtonian flow properties. Dynamic light scattering study hinted the presence of small micelles in the solution above 30 (°) C. Thus the system showed a temperature-dependent structural transition from opaque water-swollen gel to transparent micellar liquid. The formation of water-swollen fibrillar network is attributed to surfactant-additive intermolecular interactions in aqueous medium. Transition to micelle phase above 30 (°) C is related to Kraft transition which is observed at significantly lower temperature for CTAB in the absence of PCA. The structural features of PCA play a key role in promoting fibrillar network formation and elevating the Kraft transition in aqueous solution of CTAB.

  18. Surfactantes reativos não-iônicos em polimerização em emulsão de látices de acetato de vinila - vinil neodecanoato: influência nas propriedades de barreira à água Nonionic reactive surfactants in emulsion polymerization of vinyl acetate - vinyl neodecanoate latexes: influence on the water barrier properties

    Directory of Open Access Journals (Sweden)

    Jorge M. de Oliveira

    2009-01-01

    during the film formation. In this work vinyl acetate - vinyl neodecanoate (VeoVa 10® latexes, stabilized with conventional and reactive nonionic surfactant, were prepared and the performance of these films was evaluated. It was noted that latexes stabilized with nonionic polymerizable surfactants can bring, under certain conditions, better barrier properties.

  19. Influence of the Surfactants on Microstructure and the Properties of Wet Coagulation Polyurethane Film

    Institute of Scientific and Technical Information of China (English)

    ZENG Yue-min; YAN Hao-jing; HU Jin-lian

    2002-01-01

    Polyurethane asymmetric membranes were prepared bywet coagulation process from the PU/DMF/Span-80/OT-70 solutions, and the morphological features of the cross section of the membranes obtained by scanning electron microscopy were presented. The influences of the non-ionic hydrophobic surfactant Span- 80 and the anionic surfactant hydrophilic OT-70 on the morphology of the membranes, the mechanical properties and the water vapor permeability were studied. The formation mechanism of the membrane microstructure from the different PU/DMF/Surfactants systems was discussed.

  20. Molecular-thermodynamic theory of micellization of multicomponent surfactant mixtures: 2. pH-sensitive surfactants.

    Science.gov (United States)

    Goldsipe, Arthur; Blankschtein, Daniel

    2007-05-22

    In article 1 of this series, we developed a molecular-thermodynamic (MT) theory to model the micellization of mixtures containing an arbitrary number of conventional (pH-insensitive) surfactants. In this article, we extend the MT theory to model mixtures containing a pH-sensitive surfactant. The MT theory was validated by examining mixtures containing both a pH-sensitive surfactant and a conventional surfactant, which effectively behave like ternary surfactant mixtures. We first compared the predicted micellar titration data to experimental micellar titration data that we obtained for varying compositions of mixed micelles containing the pH-sensitive surfactant dodecyldimethylamine oxide (C12DAO) mixed with either a cationic surfactant (dodecyltrimethylammonium bromide, C12TAB), a nonionic surfactant (dodecyl octa(ethylene oxide), C12E8), or an anionic surfactant (sodium dodecyl sulfate, SDS) surfactant. The MT theory accurately modeled the titration behavior of C12DAO mixed with C12E8. However, C12DAO was observed to interact more favorably with SDS and with C12TAB than was predicted by the MT theory. We also compared predictions to data from the literature for mixtures of C12DAO and SDS. Although the pH values of solutions with no added acid were modeled with only qualitative accuracy, the MT theory resulted in quantitatively accurate predictions of solution pH for mixtures containing added acid. In addition, the predicted degree of counterion binding yielded a lower bound to the experimentally measured value. Finally, we predicted the critical micelle concentration (cmc) of solutions of two pH-sensitive surfactants, tetradecyldimethylamine oxide (C14DAO) and hexadecyldimethyl betaine (C16Bet), at varying solution pH and surfactant composition. However, at the pH values considered, the pH sensitivity of C16Bet could be neglected, and it was equivalently modeled as a zwitterionic surfactant. The cmc's predicted using the MT theory agreed well with the experimental

  1. Use of highly saline ethoxylated surfactant system for oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Reisberg, J.

    1970-03-17

    An aqueous solution of a sulfated polyoxylated primary alcohol and a soluble inorganic electrolyte was used for enhanced oil recovery. The electrolyte should be present in a concentration exceeding the critical concentration for forming a two-phase coacervate system, by an amount sufficient to convert the two-phase system to a turbid dispersion. The dispersion permits an interfacial tension with petroleum of 10/sup -4/ dynes/cm. A berea core (400 md) was flooded to residual oil saturation before flooding with a 4 M sodium chloride brine which contained Tergitol 15-S4 (4 ethylene oxide units, sodium salt). A 1 PV slug of the surfactant solution left only about 7 percent PV of oil.

  2. Adsorptive removal of naphthalene induced by structurally different Gemini surfactants in a soil-water system.

    Science.gov (United States)

    Wei, Jia; Li, Jun; Huang, Guohe; Wang, Xiujie; Chen, Guanghui; Zhao, Baihang

    2016-09-01

    A new generation of surfactant, Gemini surfactants, have been synthesized and have attracted the attention of various industrial and academic research groups. This study focused on the use of symmetric and dissymmetric quaternary ammonium Gemini surfactants to immobilize naphthalene onto soil particles, and is used as an example of an innovative application to remove HOC in situ using the surfactant-enhanced sorption zone. The sorption capacity of modified soils by Gemini surfactant and natural soils was compared and the naphthalene sorption efficiency, in the absence and presence of Gemini surfactants with different alkyl chain lengths, was investigated in the soil-water system. The results have shown that the increased added Gemini surfactant formed admicelles at the interface of soil/water having superior capability to retard contaminant. Symmetric and dissymmetric Gemini surfactants have opposite effect on the aspect of removing of PAH attributing to their solubilization and sorption behavior in soil-water system. Compared with the natural soil, sorption of naphthalene by Gemini-modified soil is noticeably enhanced following the order of C12-2-16 < C12-2-12 < C12-2-8. However, the symmetric Gemini surfactant C12-2-12 is the optimized one for in situ barrier remediation, which is not only has relative high retention ability but also low dosage.

  3. Complex Formation Between Polyelectrolytes and Ionic Surfactants

    OpenAIRE

    1998-01-01

    The interaction between polyelectrolyte and ionic surfactant is of great importance in different areas of chemistry and biology. In this paper we present a theory of polyelectrolyte ionic-surfactant solutions. The new theory successfully explains the cooperative transition observed experimentally, in which the condensed counterions are replaced by ionic-surfactants. The transition is found to occur at surfactant densities much lower than those for a similar transition in non-ionic polymer-sur...

  4. Interactions in Calcium Oxalate Hydrate/Surfactant Systems.

    Science.gov (United States)

    Sikiric; Filipovic-Vincekovic; Babic-Ivancić Vdović Füredi-Milhofer

    1999-04-15

    Phase transformation of calcium oxalate dihydrate (COD) into the thermodynamically stable monohydrate (COM) in anionic (sodium dodecyl sulfate (SDS)) and cationic (dodecylammonium chloride) surfactant solutions has been studied. Both surfactants inhibit, but do not stop transformation from COD to COM due to their preferential adsorption at different crystal faces. SDS acts as a stronger transformation inhibitor. The general shape of adsorption isotherms of both surfactants at the solid/liquid interface is of two-plateau-type, but differences in the adsorption behavior exist. They originate from different ionic and molecular structures of crystal surfaces and interactions between surfactant headgroups and solid surface. Copyright 1999 Academic Press.

  5. Different behaviours in the solubilization of polycyclic aromatic hydrocarbons in water induced by mixed surfactant solutions.

    Science.gov (United States)

    Sales, Pablo S; de Rossi, Rita H; Fernández, Mariana A

    2011-09-01

    Water solubility of polycyclic aromatic hydrocarbons (PAHs), viz, naphthalene and phenanthrene, in micellar solutions at 25°C was investigated, using two series of different binary mixtures of anionic and nonionic surfactants. Tween 80 and Brij-35 were used as nonionic surfactants whereas fatty acids or amphiphilic cyclodextrins (Mod-β-CD) synthesized in our laboratory were used as anionic ones. Solubilization capacity has been quantified in terms of the molar solubilization ratio and the micelle-water partition coefficient, using UV-visible spectrophotometry. Anionic surfactants exhibited less solubilization capacity than nonionics. The mixtures between Tween 80 and Mod-β-CD did not show synergism to increase the solubilization of PAHs. On the other hand, the mixtures formed by Tween 80 and fatty acids at all mole fractions studied produced higher enhancements of the solubility of naphthalene than the individual surfactants. The critical micellar concentration of the mixtures of Tween 80/sodium laurate was determined by surface tension measurements and spectrofluorimetry using pyrene as probe. The system is characterized by a negative interaction parameter (β) indicating attractive interactions between both surfactants in the range of the compositions studied. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Synthesis of nanocrystalline calcium phosphate in microemulsion--effect of nature of surfactants.

    Science.gov (United States)

    Singh, Sujata; Bhardwaj, Pallavi; Singh, V; Aggarwal, S; Mandal, U K

    2008-03-01

    Nanosized calcium phosphate (CP) powders have been synthesized by an inverse microemulsion system using kerosene as the oil phase, a cationic surfactant Aliquat 336, a non-ionic surfactant Tween 20 and their mixture and aqueous solutions of calcium nitrate tetrahydrate and biammonium hydrogen phosphate as the water phase. It has been found that the nature of surfactants played an important role to regulate the size and morphologies of the calcium phosphate nanoparticles. The cationic surfactant Aliquat 336 has been found to regulate the nucleation and crystal growth. The synthesized powders have been comprehensively characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Our results show that the brushite (DCPD) is the major phase comprising the calcium phosphate nanoparticles. In mixed surfactants mediated system a morphological controlled highly crystalline particles have been synthesized. Further, the role of Aliquat 336 has been established and a plausible synthetic mechanism has been proposed.

  7. Order-disorder transitions in comb-like polymer-surfactant systems involving hydrogen bonds

    NARCIS (Netherlands)

    ten Brinke, G.; Huh, J; Ruokolainen, J.; Torkkeli, M.; Serimaa, R.; Ikkala, O.

    Conditions to obtain micro-phase separated morphologies in polymer-surfactant systems involving hydrogen bonds have been investigated using poly(4-vinyl pyridine) (P4VP) and surfactants capable of forming hydrogen bonds of different strength with the basic nitrogen of P4VP. Depending on the tail

  8. The Effect of Surfactant on Synthesis of ZSM-5 in a Super-Concentrated System

    Institute of Scientific and Technical Information of China (English)

    Li Haiyan; Qin Lihong; Gao Guangbo; Sun Famin

    2016-01-01

    ZSM-5 zeolite was synthesized in a super-concentrated system using different kinds of surfactants. The ZSM-5 samples were characterized by XRD, SEM, FT-IR and BET techniques. The surfactant could change the properties of ZSM-5 zeolite, including the crystallinity, the crystal grain size, the surface area, the pore volume and the Si/Al mole ratio.

  9. Rheological characterization of polysaccharide-surfactant matrices for cosmetic O/W emulsions.

    Science.gov (United States)

    Bais, D; Trevisan, A; Lapasin, R; Partal, P; Gallegos, C

    2005-10-15

    Rheometrical techniques can be profitably used for polysaccharide matrices in order to evaluate their suitability for the preparation of stable cosmetic O/W emulsions. In particular, the rheological properties of aqueous scleroglucan systems were investigated under continuous and oscillatory shear conditions in a polymer concentration range (0.2-1.2% w/w) embracing the sol/gel transition. The effects due to the addition of two different surfactants (up to 10% w/w) were examined at constant polymer concentration (0.4% w/w). The selected additives are a nonionic polymeric siliconic surfactant (dimethicone copolyol) and a cationic surfactant (tetradecyltrimethylammonium bromide), respectively. Polysaccharide-surfactant interactions leading to complex formation were detected also through rheology. The combined action of both nonionic and cationic surfactants in the polymer solution was examined at two different surfactant concentration levels (5 and 10% w/w), demonstrating the beneficial effects produced on the mechanical properties of the polymer matrix by the coexistence of both surfactants. Such beneficial effects are confirmed by the stability and rheology shown by the emulsions prepared. In this way, the results point out the good agreement between the rheology of the continuous phase and the final characteristics of the emulsion obtained.

  10. Size separation of analytes using monomeric surfactants

    Science.gov (United States)

    Yeung, Edward S.; Wei, Wei

    2005-04-12

    A sieving medium for use in the separation of analytes in a sample containing at least one such analyte comprises a monomeric non-ionic surfactant of the of the general formula, B-A, wherein A is a hydrophilic moiety and B is a hydrophobic moiety, present in a solvent at a concentration forming a self-assembled micelle configuration under selected conditions and having an aggregation number providing an equivalent weight capable of effecting the size separation of the sample solution so as to resolve a target analyte(s) in a solution containing the same, the size separation taking place in a chromatography or electrophoresis separation system.

  11. Organofilização de argilas bentoníticas com tensoativos não- iônicos visando seu uso em fluidos de perfuração base óleo Nonionic surfactants organophilization bentonite clays aiming their use in oil base drilling fluids

    Directory of Open Access Journals (Sweden)

    I. A. Silva

    2012-09-01

    Full Text Available O uso de tensoativos não iônicos vem substituindo os tradicionais tensoativos iônicos dentre outros motivos pelo seu elevado potencial de resistência a degradação térmica. Assim, este trabalho tem por objetivo o desenvolvimento de argilas organofílicas através da incorporação de tensoativos não iônicos visando seu uso em fluidos de perfuração de poços de petróleo base óleo. Argilas bentoníticas natural, industrializadas e organofilizadas foram caracterizadas por análise química, difração de raios X e análises térmicas. Após a organofilização foi realizado o inchamento de Foster, visando a escolha dos tensoativos mais adequados aos meios líquidos orgânicos dispersantes: éster, diesel e parafina. Com as dispersões obtidas foram determinadas as propriedades reológicas através de viscosidades aparente e plástica. Os resultados evidenciaram que as argilas organofilicas apresentaram um aumento do espaçamento interlamelar e que as dispersões apresentaram propriedades reológicas dentro das especificações da Petrobrás, para uso como argilas organofílicas em fluidos de perfuração em base óleo.The nonionic surfactants use is replacing the traditional ionic surfactants among other reasons because of its high resistance to thermal degradation potential. This work aims the organoclays development through the nonionic surfactants incorporation in order to oil base drilling fluids use. The natural bentonite clay, and industrialized organophilizated were characterized by chemical analysis, X-ray diffraction and thermal analysis. After, the clay organophilization was performed by Foster swelling, seeking the most appropriate choice of surfactants to the liquid media organic dispersants, ester, paraffin and diesel. With the obtained dispersions were determined by plastic and apparent viscosities the rheological properties. The results showed that organoclays increase in the interlayer spacing and that the dispersions

  12. 污灌条件下非离子表面活性剂对土壤中有机农药迁移的影响研究%Effect of Nonionic Surfactant on Organic Pesticide Migration in Soil Under Sewage Irrigation Conditions

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    采用振荡平衡法和淋洗法,研究了污灌条件下非离子表面活性剂Tween-80在表层土壤和深层土壤上的吸附行为及其对有机农药甲萘威迁移的影响。结果表明:在振荡平衡条件下,低Tween-80浓度的污水灌溉会促进甲萘威在表层土壤中的吸附,而高Tween-80浓度的污水灌溉会抑制甲萘威在深层土壤中的吸附;在淋洗条件下,Tween-80在深层土壤中表现出较强的吸附能力。%By using batch adsorption and leaching adsorption method, adsorption behaviors of nonionic surfactant Tween-80 in topsoil or deep soil were compared and their effect on migration of organic pesticide carbaryl in soil under sewage irrigation con-ditions were investigated.The results of the batch adsorption experiments showed that low Tween -80 concentration wastewater ir-rigation increased the adsorption of carbaryl in topsoil.On the contrary, high Tween-80 concentration wastewater irrigation re-duced the adsorption of carbaryl in deep soil and increased the migration of organic pesticide in deep soil.Under leaching adsorp-tion condition, the higher adsorption of nonionic surfactant Tween-80 in soil was observed.

  13. New electrolyte systems for capillary zone electrophoresis of metal cations and non-ionic organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Y.

    1995-06-19

    Excellent separations of metal ions can be obtained very quickly by capillary electrophoresis provided a weak complexing reagent is incorporated into the electrolyte to alter the effective mobilities of the sample ions. Indirect photometric detection is possible by also adding a UV-sensitive ion to the electrolyte. Separations are described using phthalate, tartrate, lactate or hydroxyisobutyrate as the complexing reagent. A separation of twenty-seven metal ions was achieved in only 6 min using a lactate system. A mechanism for the separation of lanthanides is proposed for the hydroxyisobutyrate system.

  14. Surfactant aggregation and its application to drag reduction

    Energy Technology Data Exchange (ETDEWEB)

    Harwigsson, I.

    1995-09-01

    A number of different drag-reducing (DR) surfactants: nonionics, zwitterionics and ampholytics suitable for use in both cool and hot water solution are described. These surfactants have been tested under various conditions common in district energy distribution. The surfactants described are environmentally more acceptable than the organic salts of quaternary ammonium compounds which have so far dominated as DR surfactants. The micellar phase formed in water by the surfactant system cetylpyridinium chloride/sodium salicylate has been investigated with surfactant self-diffusion (NMR) measurements and cryo-transmission electron microscopy. Results from this study support the hypothesis that worm-like micellar systems form a network before the phase boundary, when the first liquid crystalline phase formed is a bicontinuous cubic phase. A series of surfactants similar to the one used in the DR experiments has been examined in dilute solutions. Critical micellar concentration and the size of these micelles are investigated as a function of the amphiphile concentration, the pH and salt concentration. Adsorption properties on silica of zwitterionic dodecyl-N,N-dimethylammonio alkanoates, with polymethylene interchange arms of different lengths, have been investigated with an in situ ellipsometry technique. The use of two-tone frequency modulation spectroscopy as a general method for the determination of water activity has been initiated. 173 refs, 6 figs

  15. Research on surfactant flooding in high temperature and high-salinity reservoir for enhanced oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Ming [Southwest Petroleum Univ., Chengdu, Sichuan (China). State Key Lab. of Oil and Gas Reservoir Geology and Exploitation; Southwest Petroleum Univ., Chengdu, Sichuan (China). School of Material Science and Engineering; Zhao, Jinzhou; Yang, Yan [Southwest Petroleum Univ., Chengdu, Sichuan (China). State Key Lab. of Oil and Gas Reservoir Geology and Exploitation; Wang, Xu [Southwest Petroleum Univ., Chengdu, Sichuan (China). School of Material Science and Engineering

    2013-05-15

    The aim of this work was to research the solution properties of a new surfactant flooding system for high temperature and high salinity reservoir, which include trimeric sulfonate surfactants 1,2,3-tri(2-oxypropyl sulfonation-3-alkylether-propoxyl) propanes (TTSS-n) and anion-nonionic surfactant NPSO [sodium nonyl phenol polyethyleneoxy ether sulfonate, (EO = 10)]. The critical micelle concentrations (CMCs) of five trimeric sulfonate surfactants were smaller than 400 mg L{sup -1}. Furthermore, their interfacial tensions (IFTs) could reach an ultralow value with Tazhong 4 oil at lower concentrations. Through optimized formulation, we found that TTSS-12 had better properties and was selected as the major component of the surfactant flooding system. We designed an optimal formulation of the surfactant flooding system with 1000 mg . L{sup -1} TTSS-12 and 1000 mg . L{sup -1} NPSO surfactant. The system with a very small surfactant concentration could reach ultralow IFT with Tazhong 4 crude oils at high temperature (110 C) and high concentration formation brine (112,228.8 mg/L TDS), which proved that the simpler component surfactant had better reservoir compatibility. NPSO could weaken the disadvantage of the surfactant TTSS-12 in oil/water interface. The stability of this surfactant flooding system was evaluated by aging time, static adsorption and chromatographic separation. All experiments showed that it still keeps ultralow IFT in high temperature and high salinity conditions. Coreflooding experimentation showed that average oil recovery reached 9.8 wt% by surfactant flooding, therefore, it is feasible to use as a surfactant flooding system for enhanced oil recovery (EOR). (orig.)

  16. Some aspects of surfactant action mechanism in the organic reagents - metal ions systems

    Energy Technology Data Exchange (ETDEWEB)

    Chernova, R.K.; Shtykov, S.N.; Beloliptseva, G.M.; Sukhova, L.K.; Amelin, V.G.; Kulapina, E.G. (Saratovskij Gosudarstvennyj Univ. (USSR))

    1984-06-01

    Results are reviewed of investigations into the interaction of ions of Mo(6), W, Zr, Be, Sc, Nb, Ta, J, rare earths, a. o. with organic reagents of triphenylmethane class in the 8M H/sub 2/SO/sub 4/-pH14 acidity range and the 1x10/sup -3/-5x10/sup -6/ M concentration range both in the presence and absence of different surfactant type (cetylpyridine, methyltrimethylammonium, synthanols, etc). Three types of effects, determining enhancement of the sensitivity and selectivity of reactions jn the Me-R-surfactant systems, were determined: an increase in the number of coordinated ligands, the activating effect of cation surfactants resulting in a potential complexing in acid media, multicenter interaction of polydentate ligands both via chelating groups and auxochrome groups in the presence of cation surfactants. Protolytic and flotation properties of ionic associates are considered. The observed effects are explained from the viewpoint of electrostatic and hydrophobic interactions in the R-surfactant systems, observed by the methods of NMR, polarography amperometry, conductometry. A possible use of the investigated M-R-surfactant systems as complexonometric indicators was evaluated. A possibility was shown of using them for direct titrimetric determination of hundredth milligram portions of Cu, Ga, In and Sc at a titrant concentratjon of less than 0.01 M. It follows from the estimation of basic optical parameters of the Me-R-surfactant systems that detection.

  17. A systems approach to mapping transcriptional networks controlling surfactant homeostasis

    Directory of Open Access Journals (Sweden)

    Dave Vrushank

    2010-07-01

    Full Text Available Abstract Background Pulmonary surfactant is required for lung function at birth and throughout life. Lung lipid and surfactant homeostasis requires regulation among multi-tiered processes, coordinating the synthesis of surfactant proteins and lipids, their assembly, trafficking, and storage in type II cells of the lung. The mechanisms regulating these interrelated processes are largely unknown. Results We integrated mRNA microarray data with array independent knowledge using Gene Ontology (GO similarity analysis, promoter motif searching, protein interaction and literature mining to elucidate genetic networks regulating lipid related biological processes in lung. A Transcription factor (TF - target gene (TG similarity matrix was generated by integrating data from different analytic methods. A scoring function was built to rank the likely TF-TG pairs. Using this strategy, we identified and verified critical components of a transcriptional network directing lipogenesis, lipid trafficking and surfactant homeostasis in the mouse lung. Conclusions Within the transcriptional network, SREBP, CEBPA, FOXA2, ETSF, GATA6 and IRF1 were identified as regulatory hubs displaying high connectivity. SREBP, FOXA2 and CEBPA together form a common core regulatory module that controls surfactant lipid homeostasis. The core module cooperates with other factors to regulate lipid metabolism and transport, cell growth and development, cell death and cell mediated immune response. Coordinated interactions of the TFs influence surfactant homeostasis and regulate lung function at birth.

  18. Nanofiltration: ion exchange system for effective surfactant removal from water solutions

    Directory of Open Access Journals (Sweden)

    I. Kowalska

    2014-12-01

    Full Text Available A system combining nanofiltration and ion exchange for highly effective separation of anionic surfactant from water solutions was proposed. The subjects of the study were nanofiltration polyethersulfone membranes and ion-exchange resins differing in type and structure. The quality of the treated solution was affected by numerous parameters, such as quality of the feed solution, membrane cut-off, resin type, dose and the solution contact time with the resin. A properly designed purification system made it possible to reduce the concentration of anionic surfactant below 1 mg L-1 from feed solutions containing surfactant in concentrations above the CMC value.

  19. Effect of surfactants on shear-induced gelation and gel morphology of soft strawberry-like particles.

    Science.gov (United States)

    Xie, Delong; Arosio, Paolo; Wu, Hua; Morbidelli, Massimo

    2011-06-07

    The role of surfactant type in the aggregation and gelation of strawberry-like particles induced by intense shear without any electrolyte addition is investigated. The particles are composed of a rubbery core, partially covered by a plastic shell, and well stabilized by fixed (sulfate) charges in the end group of the polymer chains originating from the initiator. In the absence of any surfactant, after the system passes through a microchannel at a Peclet number equal to 220 and a particle volume fraction equal to 0.15, not only shear-induced gelation but also partial coalescence among the particles occurs. The same shear-induced aggregation/gelation process has been carried out in the presence of an ionic (sulfonate) surfactant or a nonionic (Tween 20) steric surfactant. It is found that for both surfactants shear-induced gelation does occur at low surfactant surface density but the conversion of the primary particles to the clusters constituting the gel decreases as the surfactant surface density increases. When the surfactant surface density increases above certain critical values, shear-induced gelation and eventually even aggregation do not occur any longer. For the sulfonate surfactant, this was explained in the literature by the non-DLVO, short-range repulsive hydration forces generated by the adsorbed surfactant layer. In this work, it is shown that the steric repulsion generated by the adsorbed Tween 20 layer can also protect particles from aggregation under intense shear. Moreover, the nonionic steric surfactant can also protect the strawberry-like particles from coalescence. This implies a decrease in the fractal dimension of the clusters constituting the gel from 2.76 to 2.45, which cannot be achieved using the ionic sulfonate surfactant.

  20. Determining scaling in known phase diagrams of nonionic microemulsions to aid constructing unknown.

    Science.gov (United States)

    Balogh, Joakim

    2010-08-11

    Microemulsions based on nonionic surfactants of the ethylene oxide alkyl ether type C(m)E(n), have been studied thoroughly for around 30 years. Thanks to the considerable amount of published data available on these systems, it is possible to observe trends to make predictions of phase diagrams not yet determined. Strey and Kahlweit, and subsequently Sottmann and Strey, with coworkers have studied and published phase diagrams for systems with a fixed ratio of oil to water, varying the surfactant, the so-called Kahlweit fish-cut diagrams. Some properties of the phase diagrams can be scaled to become general and not system dependent. Here are shown two examples of scaling data from phase diagrams and the use of trends to determine phase diagrams, both inside and outside a dataset. The trends of microemulsions with fixed ratio of surfactant to oil, the so-called Lund-cut diagrams, are also investigated. The trends are used to determine a new phase diagram and this is compared with previously unpublished experimental data on C(12)E(5)-Octadecane-Water system. The scalings and trends make it possible to get good estimations of many of the important properties of the phase diagrams, both temperatures and surfactant concentrations of interest, by investigating one sample in the 3-phase region of the balanced fish-cut diagram.

  1. VESICLE-SURFACTANT INTERACTIONS - EFFECTS OF ADDED SURFACTANTS ON THE GEL TO LIQUID-CRYSTAL TRANSITION FOR 2 VESICULAR SYSTEMS

    NARCIS (Netherlands)

    Blandamer, M.J; Briggs, B.; Cullis, P.M.; Engberts, J.B.F.N.; Kacperska, A.

    1995-01-01

    Interactions of both cationic and anionic surfactants with vesicles formed by dimethyldioctadecylammonium bromide (DOAB) and by sodium didodecylphosphate (DDP) have been probed using differential scanning microcalorimetry. The scans show that the surfactants are incorporated into the vesicle bilayer

  2. Vesicle-Surfactant Interactions : Effects of Added Surfactants on the Gel to Liquid-crystal Transition for Two Vesicular Systems

    NARCIS (Netherlands)

    Blandamer, Michael J.; Briggs, Barbara; Cullis, Paul M.; Engberts, Jan B.F.N.; Kacperska, Anna

    1995-01-01

    Interactions of both cationic and anionic surfactants with vesicles formed by dimethyldioctadecylammonium bromide (DOAB) and by sodium didodecylphosphate (DDP) have been probed using differential scanning microcalorimetry. The scans show that the surfactants are incorporated into the vesicle bilayer

  3. Key interactions of surfactants in therapeutic protein formulations: A review.

    Science.gov (United States)

    Khan, Tarik A; Mahler, Hanns-Christian; Kishore, Ravuri S K

    2015-11-01

    Proteins as amphiphilic, surface-active macromolecules, demonstrate substantial interfacial activity, which causes considerable impact on their multifarious applications. A commonly adapted measure to prevent interfacial damage to proteins is the use of nonionic surfactants. Particularly in biotherapeutic formulations, the use of nonionic surfactants is ubiquitous in order to prevent the impact of interfacial stress on drug product stability. The scope of this review is to convey the current understanding of interactions of nonionic surfactants with proteins both at the interface and in solution, with specific focus to their effects on biotherapeutic formulations.

  4. Phosphine oxide surfactants revisited.

    Science.gov (United States)

    Stubenrauch, Cosima; Preisig, Natalie; Laughlin, Robert G

    2016-04-01

    This review summarizes everything we currently know about the nonionic surfactants alkyl dimethyl (C(n)DMPO) and alkyl diethyl (C(n)DEPO) phosphine oxide (PO surfactants). The review starts with the synthesis and the general properties (Section 2) of these compounds and continues with their interfacial properties (Section 3) such as surface tension, surface rheology, interfacial tension and adsorption at solid surfaces. We discuss studies on thin liquid films and foams stabilized by PO surfactants (Section 4) as well as studies on their self-assembly into lyotropic liquid crystals and microemulsions, respectively (Section 5). We aim at encouraging colleagues from both academia and industry to take on board PO surfactants whenever possible and feasible because of their broad variety of excellent properties.

  5. Kinetics of degradation of surfactant-solubilized fluoranthene by a Sphingomonas paucimobilis

    Energy Technology Data Exchange (ETDEWEB)

    Willumsen, P.A. (National Environmental Research Institute, Roskilde (Denmark). Dept. of Marine Ecology and Microbiology); Arvin, E. (Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Environmental Science and Engineering)

    1999-08-01

    To achieve a better quantitative understanding of the stimulating or inhibiting effect of surfactants on the metabolism of polycyclic aromatic hydrocarbons (PAHs), a biodegradation model describing solubilization, bioavailability, and biodegradation of crystalline fluoranthene is proposed and used to model experimental data. The degradation was investigated in batch systems containing the PAH-degrading bacterium Sphingomonas paucimobilis strain EPA505, the nonionic surfactant Triton X-100, and a fluoranthene-amended liquid mineral salts medium. Surfactant-enhanced biodegradation is complex; however, the biodegradation model predicted fluoranthene disappearance and the initial mineralization well. Surfactant-amendment did increase fluoranthene mineralization rates by strain EPA505; however, the increases were not proportional to the rates of fluoranthene solubilization. The surfactant clearly influenced the microbial PAH metabolism as indicated by a rapid accumulation of colored products and by a surfactant -related decreased in the overall extent of fluoranthene mineralization. Model estimations of the bioavailability of micelle-solubilized fluoranthene, the relatively fast fluoranthene disappearance, and the accumulation of extracellular compounds in the degradation system suggest that low availability of micellar fluoranthene is not the only factor controlling surfactant-enhanced biodegradation. Also factors such as the extent of accumulation and bioavailability of the PAH metabolites and the crystalline solubilization rate in the presence of surfactants may determine the overall effect of surfactant-enhanced biodegradation of high molecular weight PAHs.

  6. Thermodynamic aspects of polymer–surfactant interactions: Gemini (16-5-16-PVP-water system

    Directory of Open Access Journals (Sweden)

    Naved Azum

    2016-11-01

    Full Text Available The interaction between polyvinylpyrrolidone (PVP and gemini surfactant (16-5-16 in aqueous solution has been analyzed using conductometry. From conductivity data the critical aggregation concentration (cac, critical micelle concentration (cmc, the effective degree of counter-ion binding (β at different temperatures were obtained. The thermodynamic parameters, i.e., Gibbs energy of aggregation and micellization, standard enthalpy of aggregation, and standard entropy of aggregation of surfactant/polymer system were estimated, employing pseudophase separation model. The negative values of Gibbs energy and standard enthalpy suggest that the surfactant/polymer aggregation process is spontaneous and exothermic respectively.

  7. Solubilization of octane in electrostatically-formed surfactant-polymer complexes.

    Science.gov (United States)

    Zhang, Hui; Zeeb, Benjamin; Salminen, Hanna; Feng, Fengqin; Weiss, Jochen

    2014-03-01

    Polymers can be used to modulate the stability and functionality of surfactant micelles. The purpose of this study was to investigate the solubilization of an octane oil-in-water emulsion in mixtures of an anionic polymer (carboxymethyl cellulose) and anionic sodium dodecylsulphate (SDS), nonionic polyoxyethylene sorbitan monooleate (Tween 80) and cationic cetyltrimethylammonium bromide (CTAB) surfactant micelles using dynamic light scattering, microelectrophoresis and turbidity measurements. The results showed that the addition of anionic carboxymethyl cellulose accelerated octane solubilization in cationic CTAB and CTAB-Tween 80 micelles, but did not affect the solubilization behaviors of micelles that were nonionic and anionic. The surfactant-polymer interactions were also studied using isothermal titration calorimetry (ITC) to characterize different physiochemical interaction regions depending on surfactant concentration in surfactant-polymer systems. Upon octane solubilization in CTAB-carboxymethyl cellulose mixtures, shape transitions of polymer-micelle complexes may have taken place that altered light scattering behavior. Based on these results, we suggest a mechanism for oil solubilization in electrostatically-formed surfactant-polymer complexes.

  8. Interaction of Sodium Hyaluronate with a Biocompatible Cationic Surfactant from Lysine: A Binding Study.

    Science.gov (United States)

    Bračič, Matej; Hansson, Per; Pérez, Lourdes; Zemljič, Lidija F; Kogej, Ksenija

    2015-11-10

    Mixtures of natural and biodegradable surfactants and ionic polysaccharides have attracted considerable research interest in recent years because they prosper as antimicrobial materials for medical applications. In the present work, interactions between the lysine-derived biocompatible cationic surfactant N(ε)-myristoyl-lysine methyl ester, abbreviated as MKM, and the sodium salt of hyaluronic acid (NaHA) are investigated in aqueous media by potentiometric titrations using the surfactant-sensitive electrode and pyrene-based fluorescence spectroscopy. The critical micelle concentration in pure surfactant solutions and the critical association concentration in the presence of NaHA are determined based on their dependence on the added electrolyte (NaCl) concentration. The equilibrium between the protonated (charged) and deprotonated (neutral) forms of MKM is proposed to explain the anomalous binding isotherms observed in the presence of the polyelectrolyte. The explanation is supported by theoretical model calculations of the mixed-micelle equilibrium and the competitive binding of the two MKM forms to the surface of the electrode membrane. It is suggested that the presence of even small amounts of the deprotonated form can strongly influence the measured electrode response. Such ionic-nonionic surfactant mixtures are a special case of mixed surfactant systems where the amount of the nonionic component cannot be varied independently as was the case for some of the earlier studies.

  9. Micellization Behavior of an Amphiphilic Drug Promethazine Hydrochloride-Surfactant System in an Aqueous Medium%水溶液中两亲药物盐酸异丙嗪,表面活性剂体系的胶束化行为

    Institute of Scientific and Technical Information of China (English)

    KABIR-UD-DIN; KHAN Abbul Bashar; NAQVI Andleeb Z.

    2011-01-01

    The behavior of the mixed amphiphilic drug promethazine hydrochloride (PMT) and cationic as well as nonionic surfactants was studied by tensiometry.The cmc values of the PMT-surfactant systems decrease at a surfactant mole fraction of 0.1 and it then becomes constant.The critical micelle concentration (cmc) values are lower than the ideal cmc (cmc*) values for PMT/TX-100,PMT/TX-114,PMT/Tween 20,and PMT/Tween 60 systems.For the PMT/Tween 40,PMT/Tween 80,PMT/CPC,andPMT/CPB systems the cmc values are close to the cmc* values.This indicates that PMT forms mixed micelles with these surfactants by attractive interactions.The surface excess (Γmax) decreases in the presence of surfactants.The rigid structure of the drug makes adsorption easier and the contribution of the surfactant at the interface decreases.The interaction parametersβm (for the mixed micelles) andβ°(for the mixed monolayer) are negative indicating attraction among the mixed components.

  10. Rheologycal properties of sodium carboxymethylcellulose in the presence of electrolyte and mixed micelle of surfactants

    Directory of Open Access Journals (Sweden)

    Sovilj Verica J.

    2003-01-01

    Full Text Available One of the most significant aspects of polymer-surfactant interaction, from the practical point of view, is that of rheology control and viscosity enhancement. In the oppositely charged polyelectrolyte-surfactant system strong ionic interaction often leads to precipitation of the formed complex yielding serious problems. In this paper the interaction between anionic polyelectrolyte - sodium carboxymethylcellulose (NaCMC and cationic surfactant - cethyltrimethylammonium bromide (CTMAB has been investigated by rheological measurements. Addition of electrolyte NaBr and nonionic surfactant - Tween 80 reduced the binding strength, prevented the precipitation of the complex and increased the viscosity of the system. It was found that rheological properties are strong influenced by NaCMC-CTMAB interaction and the system exhibits either pseudoplastic or thixotropic or rheopectic behavior according to the intensity of interaction.

  11. Nonionic Microemulsions as Solubilizers of Hydrophobic Drugs: Solubilization of Paclitaxel

    Directory of Open Access Journals (Sweden)

    Jen-Ting Lo

    2016-09-01

    Full Text Available The strategy using nonionic microemulsion as a solubilizer for hydrophobic drugs was studied and is demonstrated in this work. The aqueous phase behaviors of mixed nonionic surfactants with various oils at 37 °C are firstly constructed to give the optimal formulations of nonionic microemulsions with applications in the enhanced solubilization of the model hydrophobic drug, paclitaxel, at 37 °C. Briefly, the suitable oil phase with paclitaxel significantly dissolved is microemulsified with appropriate surfactants. Surfactants utilized include Tween 80, Cremophor EL, and polyethylene glycol (4.3 cocoyl ether, while various kinds of edible oils and fatty esters are used as the oil phase. On average, the apparent solubility of paclitaxel is increased to ca. 70–100 ppm in the prepared microemulsions at 37 °C using tributyrin or ethyl caproate as the oil phases. The sizes of the microemulsions attained are mostly from ca. 60 nm to ca. 200 nm. The cytotoxicity of the microemulsion formulations is assessed with the cellular viability of 3T3 cells. In general, the cell viability is above 55% after 24 h of cultivation in media containing these microemulsion formulations diluted to a concentration of total surfactants equal to 50 ppm and 200 ppm.

  12. Enhanced oil recovery by surfactant-enhanced volumetric sweep efficiency: First annual report for the period September 30, 1985-September 30, 1986. [Sandpacks

    Energy Technology Data Exchange (ETDEWEB)

    Harwell, J H; Scamehorn, J F

    1987-05-01

    Surfactant-enhanced volumetric sweep efficiency is a novel EOR method which utilizes precipitation/coacervation of surfactants to plug the most permeable regions of the reservoir, improving the efficiency of a waterflooding operation. This technique does not rely on reduction of interfacial tension between aqueous and oleic phases to enhance oil recovery. Therefore, even though surfactants are involved, this new technique is not a substitute or improvement on classical surfactant flooding; however, it has the potantial to compete with polymer flooding as an alternative sweep efficiency improvement method. In surfactant-enhanced volumetric sweep efficiency, a slug containing one kind of surfactant is injected into the reservoir, followed by a brine spacer. This is followed by injection of a second kind of surfactant which has lower adsorption than the first surfactant used. Anionic and cationic surfactants are one possible combination for this application. These may form either a precipitate or a coacervate upon mixing. Phase boundaries for some specific systems of this type have been determined over a wide range of conditions and a model developed to describe this behavior. Another possibility is the use of nonionic surfactants, which may form coacervate under proper conditions. The adsorption behavior of mixtures of anionic and nonionic surfactants was measured to aid in modeling the chromatographic effects with these surfactants in the reservoir. Studies with sandpacks of different permeabilities in parallel configuration using mixtures of anionic and cationic surfactants have demonstrated the capability of this method to reduce flow rates through a more permeable sandpack more than that through a less permeable sandpack. 4 refs., 23 figs., 8 tabs.

  13. Phase behavior and molecular thermodynamics of coacervation in oppositely charged polyelectrolyte/surfactant systems: a cationic polymer JR 400 and anionic surfactant SDS mixture.

    Science.gov (United States)

    Li, Dongcui; Kelkar, Manish S; Wagner, Norman J

    2012-07-17

    Coacervation in mixtures of polyelectrolytes and surfactants with opposite charge is common in nature and is also technologically important to consumer health care products. To understand the complexation behavior of these systems better, we combine multiple experimental techniques to systematically study the polymer/surfactant binding interactions and the phase behavior of anionic sodium dodecyl sulfate (SDS) surfactant in cationic JR 400 polymer aqueous solutions. The phase-behavior study resolves a discrepancy in the literature by identifying a metastable phase between the differing redissolution phase boundaries reported in the literature for the surfactant-rich regime. Isothermal titration calorimetry analyzed within the framework of the simple Satake-Yang model identifies binding parameters for the surfactant-lean phase, whereas a calculation for polymer-bound micelles coexisting with free micelles is analyzed in the surfactant-rich redissolution regime. This analysis provides a preliminary understanding of the interactions governing the observed phase behavior. The resulting thermodynamic properties, including binding constants and the molar Gibbs free energies, enthalpies, and entropies, identify the relative importance of both hydrophobic and electrostatic interactions and provide a first approximation for the corresponding microstructures in the different phases. Our study also addresses the stability and metastability of oppositely charged polyelectrolytes and surfactant mixtures.

  14. EXPERIMENTAL CHARACTERIZATION OF FLUOROCARBON-MODIFIED POLYACRYLAMIDE/SURFACTANT AQUEOUS SOLUTIONS

    Institute of Scientific and Technical Information of China (English)

    Huai-tian Bu; Zhen-zhong Yang; Yun-xiang Zhang

    2003-01-01

    The interaction between surfactants and fluorocarbon-modified polyacrylamide (FC-PAM) in aqueous solutions was evaluated by theological means and fluorescence spectroscopy and was found to be strong regardless of the surfactant's nature. Two representative surfactants, anionic sodium dodecyl sulfate (SDS) and nonionic Triton X-100, were used. The origin of the interaction and its dependence on the surfactant concentration were discussed.

  15. Effect of surfactant and surfactant blends on pseudoternary phase diagram behavior of newly synthesized palm kernel oil esters

    Directory of Open Access Journals (Sweden)

    Mahdi ES

    2011-06-01

    Full Text Available Elrashid Saleh Mahdi1, Mohamed HF Sakeena1, Muthanna F Abdulkarim1, Ghassan Z Abdullah1,3, Munavvar Abdul Sattar2, Azmin Mohd Noor11Department of Pharmaceutical Technology, 2Department of Physiology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Minden, Penang, Malaysia; 3Department of Pharmaceutical Technology, International Medical University, Bukit Jalil, Kuala Lumpur, MalaysiaBackground: The purpose of this study was to select appropriate surfactants or blends of surfactants to study the ternary phase diagram behavior of newly introduced palm kernel oil esters.Methods: Nonionic surfactant blends of Tween® and Tween®/Span® series were screened based on their solubilization capacity with water for palm kernel oil esters. Tween® 80 and five blends of Tween® 80/Span® 80 and Tween® 80/Span® 85 in the hydrophilic-lipophilic balance (HLB value range of 10.7–14.0 were selected to study the phase diagram behavior of palm kernel oil esters using the water titration method at room temperature.Results: High solubilization capacity was obtained by Tween® 80 compared with other surfactants of Tween® series. High HLB blends of Tween® 80/Span® 85 and Tween® 80/Span® 80 at HLB 13.7 and 13.9, respectively, have better solubilization capacity compared with the lower HLB values of Tween® 80/Span® 80. All the selected blends of surfactants were formed as water-in-oil microemulsions, and other dispersion systems varied in size and geometrical layout in the triangles. The high solubilization capacity and larger areas of the water-in-oil microemulsion systems were due to the structural similarity between the lipophilic tail of Tween® 80 and the oleyl group of the palm kernel oil esters.Conclusion: This study suggests that the phase diagram behavior of palm kernel oil esters, water, and nonionic surfactants is not only affected by the HLB value, but also by the structural similarity between palm kernel oil esters and the surfactant

  16. Evaluation of a common commercial surfactant in a water recycle system

    Energy Technology Data Exchange (ETDEWEB)

    Rector, T.; Jackson, A.; Rainwater, K. [Texas Tech Univ., Water Resources Center, Texas (United States); Pickering, S. [Johnson Space Center, NASA, Houston, Texas (United States)

    2002-06-15

    The fate of a common commercial surfactant was investigated in the biological reactors of a water recycle system. A NO{sub 2}{sup -} reducing packed-bed bioreactor was employed to evaluate degradation of surfactant present in a typical greywater stream. The research was conducted to determine if an alternative commercial surfactant could be used in a biological water recycle system proposed for space travel in place of the current surfactant. The commercial soap used in the research was Pert Plus for Kids (PPK), which contains sodium laureth sulfate (SLES) as the active surfactant. Experiments included a combination of microcosm studies as well as a continuous-flow packed-bed bioreactor. The hydraulic retention time of the packed-bed bioreactor was varied through changes in flow rate to yield different steady-state values for NO{sub 2}-N, TOC, and COD. Steady-state values will allow the determination of the bacterial kinetic parameters. Initial results suggest that the commercial surfactant may be difficult to treat in the time frame of typical biological systems. NO{sub 2}{sup -} reduction was favorable in the packed-bed reactor, but TOC removal rates did not correspond to the NO{sub 2}{sup -} removal. It is theorized that, due to its high K{sub oc} value (1200), SLES has an affinity to absorb to the media contained in the bed, which in turn allows for adsorption of the surfactant. Future research will include development of an isotherm model to characterize the adsorption rates and correlate them to surfactant removal. (author)

  17. The ultrastructural histochemistry and stereoscanning electron microscopy of the rodent and amphibian surfactant systems.

    Science.gov (United States)

    Stratton, C J; Wetzstein, H Y; Hardy, T

    1980-05-01

    Ultrastructural histochemical precedures were employed to determine the carbohydrate components and their contributions to the rodent and amphibian surfactant systems. Zirconium stained the rodent (rat) cytoplasm surrounding the multilamellar bodies, the Golgi, and was associated with the membrane structures of the compact lamellae of alveolar multilamellar bodies. In the rodent and amphibian (Rana pipiens), ruthenium red stain was observed within all tubular myelin surfactant matricies. The "gutters," tubular myelin surfactant matrix, and intratubular myelin surfactant matrix materials all demonstrated a positive reaction product. The periodic acid-chromic acid-silver procedure revealed irregular channels extending from the multilamellar bodies to the surface of the rodent great alveolar pneumocyte. The extra-pulmonary and respiratory surfaces in both species were additionally studied by stereoscanning electron microscopy. The respiratory anatomy of the rodent was corroborated. The amphibian lung demonstrated three orders of septa, and in the expired state, tertiary septal pits. The amphibian primary septa were hollow, blind tubules containing respiratory surfaces.

  18. Anaerobic Biodegradation of Detergent Surfactants

    Directory of Open Access Journals (Sweden)

    Erich Jelen

    2009-03-01

    Full Text Available Detergent surfactantscan be found in wastewater in relevant concentrations. Most of them are known as ready degradable under aerobic conditions, as required by European legislation. Far fewer surfactants have been tested so far for biodegradability under anaerobic conditions. The natural environment is predominantly aerobic, but there are some environmental compartments such as river sediments, sub-surface soil layer and anaerobic sludge digesters of wastewater treatment plants which have strictly anaerobic conditions. This review gives an overview on anaerobic biodegradation processes, the methods for testing anaerobic biodegradability, and the anaerobic biodegradability of different detergent surfactant types (anionic, nonionic, cationic, amphoteric surfactants.

  19. Effects of Surfactant Adsorption on Surficial Wettability of Nonwoven Fabrics

    Institute of Scientific and Technical Information of China (English)

    CAI Bing; TANG Bing; LI Rui-xia; WU Da-cheng

    2002-01-01

    All types of surfactants (cationic, anionic and nonionic)reported in this paper could enhance the surficiai wettability of polypropylene (PP) and polyethylene terephthalate (PET) nonwoven fabrics. However, the effects of cationic and nonionic surfactants were better.The longer the treatment time of surfactants on the nonwoven fabrics, the better the surficial wettability.The surficial rewetting time would no longer change above a certain treatment time. The rewettability of nonwoven fabrics could be evidently improved just when the concentration of surfactants was just above the CMC,except for sodium dodecylbenzene sulfonate (LAS). The finer the fibers and the looser the structures, the better the surficial rewettability of nonwoven fabrics.

  20. Influence of surfactants on the sorption of two chloroacetanilide in an Romanian chernozem soil.

    Science.gov (United States)

    Coroi, I G; De Wilde, T; Cara, M S; Jitareanu, G; Steurbaut, W

    2011-01-01

    Pesticides have been extensively used in modern agriculture. Due to the prevalent use, there have been serious problems generated by pesticides wastes which could eventually endanger water resources and human health. The development of technologies for the decontamination of soils and waters polluted by hydrophobic organic compounds has encouraged research into the use of non-ionic surfactants as potential agents for the enhanced solubilization and removal of contaminants from soils and sediments. Sorption of two chloroacetanilide herbicides, acetochlor and metolachlor was studied on a representative chernozem soil of the Main Agricultural Research Station Ezareni belonging to the "Ion Ionescu de la Brad" University of Agriculture and Veterinary Medicine lasi, Romania, in the presence and absence of surfactants. Three different non-ionic surfactants were selected: Tween-20, Synperonic 91/5 and Silwet L-77, to verify the influence of their presence on herbicide sorption at different concentrations. Our results showed that the sorption of the studied herbicides within the soil-water-non-ionic surfactant system was influenced by the presence of non-ionic surfactants. The n values obtained were lower than 1 for all pesticide-surfactant combinations, which indicates that the amount of acetochor and metolachlor sorbed decreased with an increase in pesticide concentration. The sorption of acetochlor increased in the following order: Acetochlor+Synperonic 91/5 < Acetochlor < Acetochlor+Tween-20 < Acetochlor+Silwet L-77. In the case of metolachlor+Synperonic and metolachlor+Silwet L-77, the Kf values were significantly higher than the Kf value of metolachlor+Tween-20 on soil, where a lower Kf value could be observed with however a higher n value which indicate a higher sorption capacity at higher concentrations.

  1. Performance of some surfactants as wetting agents

    Energy Technology Data Exchange (ETDEWEB)

    Shalaby, M.N.; El-Shanny, O.A.A. [Egyptian Petroleum Research Institute (EPRI), Cairo (Egypt). Evaluation and Analysis Dept.

    2005-12-01

    The wetting power of anionic surfactant: sodium dodecyl sulfate (SDS), and nonionic surfactants: polyoxyethelene(14)monolaurate [La(EO){sub 14}] and polyoxyethelene(14)monoeleate [OI(EO){sub 14}] has been studied to determine their performance as wetting agents. The study reveals that the nonionic compound with a long hydrophobic chain exhibits higher wettability than the shorter one when used at very low cocentrations (below CMC) and the reverse is shown with high concentrations (above CMC). the wetting power of the investigated surfactants increases as the CMC values increases. In case of the nonionic compounds and at surfactant concentrations equal their CMC values, OI(EO){sub 14} shows a higher wetting power than La(EO){sub 14} while is possesses a lower HLB value. The anionic surfactant shows an optimum wetting in comparison with the tested nonionic one. The wettability of all the investigated samples increases as the surface tension of their solutions increases to the allowed limit that can be reached in the presence of surfactant. (orig.)

  2. CHARACTERIZATION OF PHASE AND EMULSION BEHAVIOR, SURFACTANT RETENTION, AND OIL RECOVERY FOR NOVEL ALCOHOL ETHOXYCARBOXYLATE SURFACTANTS

    Energy Technology Data Exchange (ETDEWEB)

    Lebone T. Moeti; Ramanathan Sampath

    2001-09-28

    This final technical report describes work performed under DOE Grant No. DE-FG26-97FT97278 during the period October 01, 1997 to August 31, 2001 which covers the total performance period of the project. During this period, detailed information on optimal salinity, temperature, emulsion morphologies, effectiveness for surfactant retention and oil recovery was obtained for an Alcohol Ethoxycarboxylate (AEC) surfactant to evaluate its performance in flooding processes. Tests were conducted on several AEC surfactants and NEODOX (23-4) was identified as the most suitable hybrid surfactant that yielded the best proportion in volume for top, middle, and bottom phases when mixed with oil and water. Following the selection of this surfactant, temperature and salinity scans were performed to identify the optimal salinity and temperature, and the temperature and salinity intervals in which all three phases coexisted. NEODOX 23-4 formed three phases between 4 and 52.5 C. It formed an aqueous rich microemulsion phase at high temperatures and an oleic rich microemulsion phase at low temperatures--a characteristic of the ionic part of the surfactant. The morphology measurement system was set-up successfully at CAU. The best oil/water/surfactant system defined by the above phase work was then studied for emulsion morphologies. Electrical conductivities were measured for middle and bottom phases of the NEODOX 23-4/dodecane/10mM water system and by mixing measured volumes of the middle phase into a fixed volume of the bottom phase and vice versa at room temperature. Electrical conductivity of the mixture decreased as the fraction of volume of the middle phase was increased and vice versa. Also inversion phenomena was observed. These experiments were then repeated for bottom/middle (B/M) and middle/bottom (M/B) conjugate pair phases at 10, 15, 25, 30, 35, 40, and 45 C. Electrical conductivity measurements were then compared with the predictions of the conductivity model developed in

  3. Degradation of polycyclic aromatic hydrocarbons in the presence of synthetic surfactants.

    OpenAIRE

    Tiehm, A

    1994-01-01

    The biodegradation of polycyclic aromatic hydrocarbons (PAH) often is limited by low water solubility and dissolution rate. Nonionic surfactants and sodium dodecyl sulfate increased the concentration of PAH in the water phase because of solubilization. The degradation of PAH was inhibited by sodium dodecyl sulfate because this surfactant was preferred as a growth substrate. Growth of mixed cultures with phenanthrene and fluoranthene solubilized by a nonionic surfactant prior to inoculation wa...

  4. Competitive interactions between components in surfactant-cosurfactant-additive systems.

    Science.gov (United States)

    Chaghi, Radhouane; de Ménorval, Louis-Charles; Charnay, Clarence; Zajac, Jerzy

    2010-04-15

    Complex interactions of phenol (PhOH), heptanol (HeOH) and heptanoic acid (HeOIC) with micellar aggregates of hexadecyltrimethylammonium bromide (HTAB) in aqueous solutions at surfactant concentrations close to the CMC, HeOH or HeOIC content of 0.5 mmol kg(-1), and phenol molality of 1, 5, or 10 mmol kg(-1) have been investigated at 303 K by means of (1)H NMR spectroscopy, titration calorimetry and solution conductimetry. The analysis of the composition-dependence of the (1)H chemical shifts assigned to selected protons in the surfactant and additive units revealed the location of PhOH both within the hydrophobic micelle core and in the vicinity of the quaternary ammonium groups, the phenol penetration being somewhat deeper in the presence of HeOIC. The phenomenon was globally more exothermic with increasing extent of PhOH solubilization and it was accompanied by a gradual decrease in the positive entropy of micellization. The solubilization was competitive for high phenol contents in the aqueous phase, with some HeOH and HeOIC units being displaced progressively towards the aqueous phase.

  5. Partition and water/oil adsorption of some surfactants.

    Science.gov (United States)

    Tadmouri, Rawad; Zedde, Chantal; Routaboul, Corinne; Micheau, Jean-Claude; Pimienta, Véronique

    2008-10-02

    Adsorption isotherms have been determined at the water/oil interface for five biphasic systems involving surfactants (non-ionic and ionic) present in both phases at partition equilibrium. The systems studied were polyoxyethylene(23)lauryl ether (Brij35) in water/hexane and four ionic surfactants, hexadecyltrimethylammonium bromide (CTAB), and a series of three tetraalkylammonium dodecylsulfate (TEADS, TPADS, and TBADS) in water/CH 2Cl 2. Interfacial tension measurements performed at the water/air and water/oil interfaces provided all the necessary information for the determination of the adsorption parameters by taking partition into account. These measurements also allowed the comparison of the adsorption properties at both interfaces which showed an increase of the adsorption equilibrium constant and a decrease of the maximum surface concentration at the water/oil interface compared to water/air. The values of the critical aggregation concentration showed, in all cases, that only the surfactant dissolved in the aqueous phase contribute to the decrease of the water/oil interfacial tension. In the case of the four ionic surfactants, the critical aggregation concentration obtained in biphasic conditions were lowered because of the formation of mixed surfactant-CH 2Cl 2 aggregates.

  6. A Review on Progress in QSPR Studies for Surfactants

    Directory of Open Access Journals (Sweden)

    Zhengwu Wang

    2010-03-01

    Full Text Available This paper presents a review on recent progress in quantitative structure-property relationship (QSPR studies of surfactants and applications of various molecular descriptors. QSPR studies on critical micelle concentration (cmc and surface tension (γ of surfactants are introduced. Studies on charge distribution in ionic surfactants by quantum chemical calculations and its effects on the structures and properties of the colloids of surfactants are also reviewed. The trends of QSPR studies on cloud point (for nonionic surfactants, biodegradation potential and some other properties of surfactants are evaluated .

  7. Phase behavior and interfacial tension studies of surfactant systems

    Energy Technology Data Exchange (ETDEWEB)

    Franses, E.I.

    1979-01-01

    Parallel studies of isomerically pure sodium P(1-heptylnonyl) benzene sulfoante, Texas No. 1, its mixture with sodium dodecyl sulfate (SDS), and the petroleum sulfonate TRS 10-80 were made. Phase behavior in water, in decane, and in water-decane mixtures was studied by spectroturbidimetry, polarizing light microscopy, ultracentrifugation, ultrafiltration, densitometry, conductimetry, low-frequency, 0.2 to 20 kHz, dielectric relaxation, isopiestic vapor pressure, and nuclear magnetic resonance spectroscopy. It was deduced that ultralow tensions (less than 0.01 dyn/cm) arise from the dispersed microcrystallites which form a third, usually liquid crystalline, phase at the decane-brine interfacial region. It appears that neither molecular adsorption from solution for micelles have anything to do with ultralow tensions, which appear to be sensitive to the third phase microstructure. The implications of these results for the mechanism of ultralow tensions in surfactant flooding processes for enhanced petroleum recovery are discussed.

  8. Use of isothermal titration calorimetry to study surfactant aggregation in colloidal systems.

    Science.gov (United States)

    Loh, Watson; Brinatti, César; Tam, Kam Chiu

    2016-05-01

    Isothermal titration calorimetry (ITC) is a general technique that allows for precise and highly sensitive measurements. These measurements may provide a complete and accurate thermodynamic description of association processes in complex systems such as colloidal mixtures. This review will address uses of ITC for studies of surfactant aggregation to form micelles, with emphasis on the thermodynamic studies of homologous surfactant series. We will also review studies on surfactant association with polymers of different molecular characteristics and with colloidal particles. ITC studies on the association of different homologous series of surfactants provide quantitative information on independent contribution from their apolar hydrocarbon chains and polar headgroups to the different thermodynamic functions associated with micellization (Gibbs energy, enthalpy and entropy). Studies on surfactant association to polymers by ITC provide a comprehensive description of the association process, including examples in which particular features revealed by ITC were elucidated by using ancillary techniques such as light or X-ray scattering measurements. Examples of uses of ITC to follow surfactant association to biomolecules such as proteins or DNA, or nanoparticles are also highlighted. Finally, recent theoretical models that were proposed to analyze ITC data in terms of binding/association processes are discussed. This review stresses the importance of using direct calorimetric measurements to obtain and report accurate thermodynamic data, even in complex systems. These data, whenever possible, should be confirmed and associated with other ancillary techniques that allow elucidation of the nature of the transformations detected by calorimetric results, providing a complete description of the process under scrutiny. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Factors affecting the design of slow release formulations of herbicides based on clay-surfactant systems. A methodological approach.

    Directory of Open Access Journals (Sweden)

    María Del Carmen Galán-Jiménez

    Full Text Available A search for clay-surfactant based formulations with high percentage of the active ingredient, which can yield slow release of active molecules is described. The active ingredients were the herbicides metribuzin (MZ, mesotrione (MS and flurtamone (FL, whose solubilities were examined in the presence of four commercial surfactants; (i neutral: two berols (B048, B266 and an alkylpolyglucoside (AG6202; (ii cationic: an ethoxylated amine (ET/15. Significant percent of active ingredient (a.i. in the clay/surfactant/herbicide formulations could be achieved only when most of the surfactant was added as micelles. MZ and FL were well solubilized by berols, whereas MS by ET/15. Sorption of surfactants on the clay mineral sepiolite occurred mostly by sorption of micelles, and the loadings exceeded the CEC. Higher loadings were determined for B266 and ET/15. The sorption of surfactants was modeled by using the Langmuir-Scatchard equation which permitted the determination of binding coefficients that could be used for further predictions of the sorbed amounts of surfactants under a wide range of clay/surfactant ratios. A possibility was tested of designing clay-surfactant based formulations of certain herbicides by assuming the same ratio between herbicides and surfactants in the formulations as for herbicides incorporated in micelles in solution. Calculations indicated that satisfactory FL formulations could not be synthesized. The experimental fractions of herbicides in the formulations were in agreement with the predicted ones for MS and MZ. The validity of this approach was confirmed in in vitro release tests that showed a slowing down of the release of a.i. from the designed formulations relative to the technical products. Soil dissipation studies with MS formulations also showed improved bioactivity of the clay-surfactant formulation relative to the commercial one. This methodological approach can be extended to other clay-surfactant systems for

  10. Competition between a lamellar and a microemulsion phase in an ionic surfactant system

    NARCIS (Netherlands)

    Kegel, W.K.; Lekkerkerker, H.N.W.

    1993-01-01

    An experimental study of a microemulsion system consisting of equal volumes of brine (water plus salt) and oil (cyclohexane), sodium dodecyl sulfate (SDS) as surfactant, and a mixture of hexanol and pentanol as cosurfactant is presented. Increasing the hexanol fraction in the cosurfactant mixture

  11. The effect of pressure on the phase behavior of surfactant systems: An experimental study

    DEFF Research Database (Denmark)

    Sandersen, Sara Bülow; Stenby, Erling Halfdan; von Solms, Nicolas

    2012-01-01

    to create microemulsions at the interface between crude oil and water, thus obtaining very low interfacial tension, which consequently helps mobilize the trapped oil.In this work a surfactant system, which has been thoroughly described at atmospheric pressure, is examined at elevated pressure. The effect...

  12. Competition between a lamellar and a microemulsion phase in an ionic surfactant system

    NARCIS (Netherlands)

    Kegel, W.K.; Lekkerkerker, H.N.W.

    1993-01-01

    An experimental study of a microemulsion system consisting of equal volumes of brine (water plus salt) and oil (cyclohexane), sodium dodecyl sulfate (SDS) as surfactant, and a mixture of hexanol and pentanol as cosurfactant is presented. Increasing the hexanol fraction in the cosurfactant mixture ca

  13. APPLICATION OF SURFACTANTS AS PULPING ADDITIVES IN SODA PULPING OF BAGASSE

    OpenAIRE

    2009-01-01

    The effects of several non-ionic commercial surfactants and their dosage on soda pulping and ECF bleaching of soda and soda-surfactant pulps of bagasse were investigated. The properties of bleachable pulps obtained with conventional soda and with soda-surfactants were studied and compared. The results showed application of surfactants during the soda pulping of bagasse decreased kappa number and improved the yield and brightness of resulting pulp. Using the surfactants reduced alkali consumpt...

  14. Evaluation of surfactant flushing for remediating EDC-tar contamination

    Science.gov (United States)

    Liang, Chenju; Hsieh, Cheng-Lin

    2015-06-01

    Ethylene dichloride tar (EDC-tar) is a dense non-aqueous phase liquid (DNAPL) waste originated from the process of vinyl chloride production, with major constituents including chlorinated aliphatic and aromatic hydrocarbons. This study investigated the feasibility of Surfactant Enhanced Aquifer Remediation (SEAR) for treating EDC-tar contaminated aquifers. Initial experiments explored the potential to enhance the apparent solubility of EDC-tar using single or mixed surfactants. The results showed that an aqueous solution mixed anionic and non-ionic surfactants (i.e., SDS/Tween 80) exhibited higher EDC-tar apparent solubility and lower surface tension than other surfactant systems tested. Additionally, alkaline pH aids in increasing the EDC-tar apparent solubility. In column flushing experiments, it was seen that the alkaline mixed SDS/Tween 80 solution showed better removal of pure EDC-tar from silica sand porous media. Furthermore, separation of EDC-tar in the surfactant solution was conducted employing a salting-out effect. Significant separation of DNAPL was observed when 13 wt.% or more NaCl was added to the solution. Overall, this study evaluates the feasibility of using SEAR for remediating EDC-tar contaminated subsurface soil and groundwater.

  15. Preliminary Testing For Anionic, Cationic and Non-ionic

    Directory of Open Access Journals (Sweden)

    Bokic, Lj.

    2007-11-01

    Full Text Available Detergents present a major environmental problem due to large quantities of surfactants released from laundries. For this reason, it is important to apply an appropriate analytical method for their determination. In this work, we propose two simple, fast and inexpensive analytical methods for anionic, cationic and non-ionic surfactant determination: thin layer chromatography (TLC separation for qualitative screening and quantitative potentiometric determination with ion-selective electrodes. These methods have been chosen because of their many advantages: rapidity, ease of operation, low cost of analysis and a wide variety of TLC application possibilities. The advantage of potentiometric titration is its very high degree of automation and very low detection limits obtained with different ion-selective electrodes applied for different surfactants.

  16. A Molecular Thermodynamic Model for Interfacial Tension in Surfactant-Oil-Water System

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    An interfacial equation of state based on perturbation theory for surfactant-oil-water system has been developed. By combining the interfacial equation of state with Boudh-Hir and Mansoori's model, a molecular ther- modynamic model has been proposed. The interfacial tension of surfactant-oil-water systems can be calculated from the surface tensions of pure oil and water by this model. The inteffacial tension data for sodium dodecyl sulphate- heptane-water system, polyoxyethylene n-octylphenol-heptane-water system and hexadecyl trimethyl ammonium bromide-heptane-water system have been correlated. By using the adjustable parameters obtained, the interfacial tensions of these systems at other temperatures have been predicted. Both the correlated and the predicted values are satisfactory.

  17. BEHAVIOR OF SURFACTANT MIXTURES AT SOLID/LIQUID AND OIL/LIQUID INTERFACES IN CHEMICAL FLOODING SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Prof. P. Somasundaran

    2002-09-30

    The aim of the project is to develop and evaluate efficient novel surfactant mixtures for enhanced oil recovery. Surfactant loss by adsorption or precipitation depends to a great extent on the type of surfactant complexes and aggregates formed. Such information as well as techniques to generate the information is lacking currently particularly for surfactant mixtures and surfactant/polymer systems. A novel analytical centrifuge application is explored during the last period to generate information on structures-performance relationship for different surfactant aggregates in solution and, in turn, at interfaces. To use analytical untracentrifuge for surfactant mixtures, information on partial specific volumes of single surfactants and their mixtures is required. Towards this purpose, surface tension and density measurements were performed to determine critical micellar concentrations (cmc), partial specific volumes of n-dodecyl-{beta}-Dmaltoside (DM), nonyl phenol ethoxylated decyl ether (NP-10) and their 1:1 mixtures at 25 C. Durchschlag's theoretical calculation method was adopted to calculate the partial specific volumes. Effects of temperature and mixing, as well as methods used for estimation on micellization and partial specific volumes were studied during the current period. Surface tension results revealed no interaction between the two surfactants in mixed micelles. Partial specific volume measurements also indicated no interaction in mixed micelles. Maximum adsorption density, area per molecule and free energy of micellization were also calculated. Partial specific volumes were estimated by two experimental methods: d{sub {rho}}/dc and V{sub {sigma}}. The difference between the results of using the two methods is within 0.5% deviation. It was found that the partial specific volume is concentration dependent and sensitive to changes in temperature. The information generated in this study will be used for the study of surfactant aggregate mass

  18. Solubilization of Hydrophobic Dyes in Surfactant Solutions

    Directory of Open Access Journals (Sweden)

    Ali Reza Tehrani-Bagha

    2013-02-01

    Full Text Available In this paper, the use of surfactants for solubilization of hydrophobic organic dyes (mainly solvent and disperse dyes has been reviewed. The effect of parameters such as the chemical structures of the surfactant and the dye, addition of salt and of polyelectrolytes, pH, and temperature on dye solubilization has been discussed. Surfactant self-assemble into micelles in aqueous solution and below the concentration where this occurs—the critical micelle concentration (CMC—there is no solubilization. Above the CMC, the amount of solubilized dye increases linearly with the increase in surfactant concentration. It is demonstrated that different surfactants work best for different dyes. In general, nonionic surfactants have higher solubilization power than anionic and cationic surfactants. It is likely that the reason for the good performance of nonionic surfactants is that they allow dyes to be accommodated not only in the inner, hydrocarbon part of the micelle but also in the headgroup shell. It is demonstrated that the location of a dye in a surfactant micelle can be assessed from the absorption spectrum of the dye-containing micellar solution.

  19. Surfactant-enhanced desorption and biodegradation of polycyclic aromatic hydrocarbons in contaminated soil.

    Science.gov (United States)

    Zhu, Hongbo; Aitken, Michael D

    2010-10-01

    We evaluated two nonionic surfactants, one hydrophobic (Brij 30) and one hydrophilic (C(12)E(8)), for their ability to enhance the biodegradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil after it had been treated in an aerobic bioreactor. The effects of each surfactant were evaluated at doses corresponding to equilibrium aqueous-phase concentrations well above the surfactant's critical micelle concentration (CMC), slightly above the CMC, and below the CMC. The concentrations of all 3- and 4-ring PAHs were significantly lower in the soil amended with Brij 30 at the two lower doses compared to controls, whereas removal of only the 3-ring PAHs was significantly enhanced at the highest Brij 30 dose. In contrast, C(12)E(8) did not enhance PAH removal at any dose. In the absence of surfactant, PAH desorbed from the soil over an 18 day period. Brij 30 addition at the lowest dose significantly increased the desorption of most PAHs, whereas the addition of C(12)E(8) at the lowest dose actually decreased the desorption of all PAHs. These findings suggest that the effects of the two surfactants on PAH biodegradation could be explained by their effects on PAH bioavailability. Overall, this study demonstrates that the properties of the surfactant and its dose relative to the corresponding aqueous-phase concentration are important factors in designing systems for surfactant-enhanced bioremediation of PAH-contaminated soils in which PAH bioavailability is limited.

  20. The application of a mulch biofilm barrier for surfactant enhanced polycyclic aromatic hydrocarbon bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Seo, Youngwoo; Lee, Woo-Hyung; Sorial, George [Department of Civil and Environmental Engineering, University of Cincinnati, 765 Baldwin Hall, PO Box 210071, Cincinnati, OH 45221-0071 (United States); Bishop, Paul L. [Department of Civil and Environmental Engineering, University of Cincinnati, 765 Baldwin Hall, PO Box 210071, Cincinnati, OH 45221-0071 (United States)], E-mail: Paul.Bishop@UC.edu

    2009-01-15

    Lab scale mulch biofilm barriers were constructed and tested to evaluate their performance for preventing the migration of aqueous and surfactant solubilized PAHs. The spatial distribution of viable PAH degrader populations and resultant biofilm formation were also monitored to evaluate the performance of the biobarrier and the prolonged surfactant effect on the PAH degrading microorganism consortia in the biobarrier. Sorption and biodegradation of PAHs resulted in stable operation of the system for dissolved phenanthrene and pyrene during 150 days of experimentation. The nonionic surfactant could increase the solubility of phenanthrene and pyrene significantly. However, the biobarrier itself couldn't totally prevent the migration of micellar solubilized phenanthrene and pyrene. The presence of surfactant and the resultant highly increased phenanthrene or pyrene concentration didn't appear to cause toxic effects on the attached biofilm in the biobarrier. However, the presence of surfactant did change the structural composition of the biofilm. - Mulch biofilm barrier showed potential for surfactant enhanced bioremediation, and the presence of surfactant changed the structural composition of the biofilm.

  1. COMBINED MICROBIAL SURFACTANT-POLYMER SYSTEM FOR IMPROVED OIL MOBILITY AND CONFORMANCE CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Jorge Gabitto; Maria Barrufet

    2004-08-01

    Many domestic oil fields are facing abandonment even though they still contain two-thirds of their original oil. A significant number of these fields can yield additional oil using advanced oil recovery (AOR) technologies. To maintain domestic oil production at current levels, AOR technologies are needed that are affordable and can be implemented by independent oil producers of the future. Microbial enhanced oil recovery (MEOR) technologies have become established as cost-effective solutions for declining oil production. MEOR technologies are affordable for independent producers operating stripper wells and can be used to extend the life of marginal fields. The demonstrated versatility of microorganisms can be used to design advanced microbial systems to treat multiple production problems in complex, heterogeneous reservoirs. The proposed research presents the concept of a combined microbial surfactant-polymer system for advanced oil recovery. The surfactant-polymer system utilizes bacteria that are capable of both biosurfactant production and metabolically-controlled biopolymer production. This novel technology combines complementary mechanisms to extend the life of marginal fields and is applicable to a large number of domestic reservoirs. The research project described in this report is performed jointly by, Bio-Engineering Inc., a woman owned small business, Texas A&M University and Prairie View A&M University, a Historically Black College and University. This report describes the results of our laboratory work to grow microbial cultures and the work done on recovery experiments on core rocks. We have selected two bacterial strains capable of producing both surfactant and polymers. We have conducted laboratory experiments to determine under what conditions surfactants and polymers can be produced from one single strain. We have conduct recovery experiments to determine the performance of these strains under different conditions. Our results do not show a

  2. A Novel Surfactant-free Microemulsion System:Ethanol/Furaldehyde/H2O

    Institute of Scientific and Technical Information of China (English)

    NI Peng; HOU Wan-Guo

    2008-01-01

    In general,a microemuision consists of oil,water,surfactant(s)and possibly cosurfactant(s).In this paper,a novel surfactant-free microemulsion(SFME)is reported,which is composed of furaldehyde(oil phase),water and ethanol without a traditional surfactant of the amphiphilic molecular structure.The phase behavior of this ternary system was studied finding that there is a single-phase microemulsion region and a two-phase region in the ternary diagram.The electrical conductivity measurement was undertaken to investigate the microregion of the single-phase microemulsion region.On the basis of the percolation theory,the single-phase microemulsion region was subdi-vided into three different microregions:furaldehyde-in-water(O/W),bicontinuous region and water-in-furaldehyde(W/O),which were confirmed by freeze-fracture transmission electron microscopy(FF-TEM)observations.The sizes of the microemulsion droplets are in the range of 30-80 nm.Some surfactant-free emulsions(SFE)reported are O/W type and turbid,the significant apparent characteristic of SFME reported here is transparent,different from the SFE.The stability change of the SFME was not evidently observed after storage at room temperature for 22 months up to now.

  3. Pulmonary haptoglobin (pHp) is part of the surfactant system in the human lung.

    Science.gov (United States)

    Abdullah, Mahdi; Goldmann, Torsten

    2012-11-20

    Since the existence of pHp was demonstrated, it has been shown that this molecule and its receptor CD163 are regulated by different stimuli. Furthermore, a comparably fast secretion of pHp was described as well as the immuno-stimulatory effects. The intention of this study was to elucidate the role of pHp in the human lungs further. Here we show, by means of confocal microscopy and immune-electron-microscopy, a clear co-localization of pHp with surfactant protein-B in lamellar bodies of alveolar epithelial cells type II. These results are underlined by immunohistochemical stainings in differently fixed human lung tissues, which show pHp in vesicular and released form. The images of the released form resemble the intended position of surfactant in the human alveolus. pHp is secreted by Alveolar epithelial cells type II as previously shown. Moreover, pHp is co-localized with Surfactant protein-B. We conclude that the presented data shows that pHp is a native part of the surfactant system in the human lung. http://www.diagnosticpathology.diagnomx.eu/vs/2563584738239912.

  4. Surfactant-assisted sol–gel synthesis of forsterite nanoparticles as a novel drug delivery system

    Energy Technology Data Exchange (ETDEWEB)

    Hassanzadeh-Tabrizi, S.A., E-mail: tabrizi1980@gmail.com [Young Researchers and Elite Club, Najafabad Branch, Islamic Azad University, Najafabad, Isfahan (Iran, Islamic Republic of); Bigham, Ashkan [Advanced Materials Research Center, Materials Engineering Department, Najafabad Branch, Islamic Azad University, Najafabad, Isfahan (Iran, Islamic Republic of); Rafienia, Mohammad [Biosensor Research Center, Isfahan University of Medical Sciences, Isfahan (Iran, Islamic Republic of)

    2016-01-01

    In the present study, forsterite nanoparticles were synthesized via surfactant-assisted sol–gel method using cetyltrimethyl ammonium bromide (CTAB) as a surfactant. The effects of CTAB contents and heat treatment on the textural properties and drug release from nanoparticles were investigated. The synthesized powders were studied by X-ray diffraction, Fourier transform infrared spectra, Brunauer–Emmett–Teller surface area analysis and transmission electron microscope images. Mg{sub 2}SiO{sub 4} materials demonstrated mesoporous characteristics and large specific surface area ranging from 159 to 30 m{sup 2}/g. The TEM results showed that forsterite nanorods had diameters about 4 nm and lengths ranging from 10 to 60 nm. It was found that the samples with 6 g CTAB show slower drug release rate than the other specimens, which is due to smaller pore size. This study revealed that the drug delivery of forsterite can be tailored by changing the amount of surfactant. - Highlights: • Forsterite nanoparticles were synthesized via surfactant-assisted sol–gel method. • Nanoparticles were loaded with ibuprofen as a novel drug delivery system. • Synthesized nanoparticles had a rod-like morphology. • CTAB concentration strongly affected the textural properties and drug release of the nanoparticles.

  5. Surfactant adsorption kinetics in microfluidics

    Science.gov (United States)

    Riechers, Birte; Maes, Florine; Akoury, Elias; Semin, Benoît; Gruner, Philipp; Baret, Jean-Christophe

    2016-10-01

    Emulsions are metastable dispersions. Their lifetimes are directly related to the dynamics of surfactants. We design a microfluidic method to measure the kinetics of adsorption of surfactants to the droplet interface, a key process involved in foaming, emulsification, and droplet coarsening. The method is based on the pH decay in the droplet as a direct measurement of the adsorption of a carboxylic acid surfactant to the interface. From the kinetic measurement of the bulk equilibration of the pH, we fully determine the adsorption process of the surfactant. The small droplet size and the convection during the droplet flow ensure that the transport of surfactant through the bulk is not limiting the kinetics of adsorption. To validate our measurements, we show that the adsorption process determines the timescale required to stabilize droplets against coalescence, and we show that the interface should be covered at more than 90% to prevent coalescence. We therefore quantitatively link the process of adsorption/desorption, the stabilization of emulsions, and the kinetics of solute partitioning—here through ion exchange—unraveling the timescales governing these processes. Our method can be further generalized to other surfactants, including nonionic surfactants, by making use of fluorophore-surfactant interactions.

  6. Estimation hydrophilic-lipophilic balance number of surfactants

    Energy Technology Data Exchange (ETDEWEB)

    Pawignya, Harsa, E-mail: harsa-paw@yahoo.co.id [Chemical Engineering Department Diponegoro University (Indonesia); Chemical Engineering Departement University of Pembangunan Nasional Yogyakarta (Indonesia); Prasetyaningrum, Aji, E-mail: ajiprasetyaningrum@gmail.com; Kusworo, Tutuk D.; Pramudono, Bambang, E-mail: Pramudono2004@yahoo.com [Chemical Engineering Department Diponegoro University (Indonesia); Dyartanti, Endah R. [Chemical Engineering Department Diponegoro University (Indonesia); Chemical Enginering Departement Sebelas Maret University (Indonesia)

    2016-02-08

    Any type of surfactant has a hydrophilic-lipophilic balance number (HLB number) of different. There are several methods for determining the HLB number, with ohysical properties of surfactant (solubility cloud point and interfacial tension), CMC methods and by thermodynamics properties (Free energy Gibbs). This paper proposes to determined HLB numbers from interfelation methods. The result of study indicated that the CMC method described by Hair and Moulik espesially for nonionic surfactant. The application of exess Gibbs free energy and by implication activity coefficient provides the ability to predict the behavior of surfactants in multi component mixtures of different concentration. Determination of HLB number by solubility and cloud point parameter is spesific for anionic and nonionic surfactant but this methods not available for cationic surfactants.

  7. Comprehensive study of tartrazine/cationic surfactant interaction.

    Science.gov (United States)

    Shahir, Afshin Asadzadeh; Javadian, Soheila; Razavizadeh, Bi Bi Marzieh; Gharibi, Hussein

    2011-12-15

    Interaction of a food dye, tartrazine, with some cationic conventional and gemini surfactants, tetradecyltrimethylammonium bromide (TTAB), N,N'-ditetradecyl-N,N,N',N'-tetramethyl-N,N'-butanediyl-diammonium dibromide (14,4,14), and N,N'-didodecyl-N,N,N',N'-tetramethyl-N,N'-butanediyl-diammonium dibromide (12,4,12), were first investigated comprehensively employing conductometry, tensiometry, and UV-visible spectroscopy. Tartrazine was found to behave in the same manner as aromatic counterions. The formation of ion pairs reflected as a considerable increase of the surfactant efficiency in tensiometry plots and their stoichiometry were determined by Job's method of continuous variations. For the tartrazine/TTAB system, nonionic DS(3), ionic DS(2-), and/or DS(2)(-) ion pairs, their small premicelles, and tartrazine-rich micelles were constituted as well as dye-containing TTAB-rich micelles. Insoluble J-aggregates of DS(-) ion pairs and cylindrical surfactant-rich micelles were also formed in tartrazine/gemini surfactant systems and recognized by transmission electron microscopy. The zeta potential and the size of the aggregates were determined using dynamic light scattering and confirmed the suggested models for the processes happening in each system. Cyclic voltammetry was applied successfully to track all of these species using tartrazine's own reduction peak current for the first time.

  8. Nonionic amphiphile nanoarchitectonics: self-assembly into micelles and lyotropic liquid crystals

    Science.gov (United States)

    Shrestha, Lok Kumar; Strzelczyk, Karolina Maria; Goswami Shrestha, Rekha; Ichikawa, Kotoko; Aramaki, Kenji; Hill, Jonathan P.; Ariga, Katsuhiko

    2015-05-01

    Amphiphiles, molecules that possess both hydrophilic and hydrophobic moieties, are architecturally simple molecules that can spontaneously self-assemble into complex hierarchical structures from lower to higher dimensions either in the bulk phase or at an interface. Recent developments in multifunctional nanostructure design using the advanced concept of nanoarchitectonics utilize this simple process of assembly. Amphiphilic self-assemblies involving lipids or proteins mimic the structure of biological systems, thus highlighting the necessity of a fundamental physical understanding of amphiphilic self-assembly towards a realization of the complex mechanisms operating in nature. Herein, we describe self-assembled microstructures of biocompatible and biodegradable tetraglycerol lauryl ether (C12G4) nonionic surfactant in an aqueous solvent system. Temperature-composition analyses of equilibrium phases identified by using small-angle x-ray scattering (SAXS) provide strong evidence of various spontaneously self-assembled mesostructures, such as normal micelles (Wm), hexagonal liquid crystal (H1), and reverse micelles (Om). In contrast to conventional poly(oxyethylene) nonionic surfactants, C12G4 did not exhibit the clouding phenomenon at higher temperatures (phase separation was not observed up to 100 °C), demonstrating the greater thermal stability of the self-assembled mesophases. Generalized indirect Fourier transformation (GIFT) evaluation of the SAXS data confirmed the formation of core-shell-type spherical micelles with a maximum dimension ca. 8.7 nm. The shape and size of the C12G4 micelles remained apparently unchanged over a wide range of concentrations (up to 20%), but intermicellar interactions increased and could be described by the Percus-Yevick (PY) theory (after Carnahan and Starling), which provides a very accurate analytical expression for the osmotic pressure of a monodisperse hard sphere.

  9. Surfactant-based critical phenomena in microgravity

    Science.gov (United States)

    Kaler, Eric W.; Paulaitis, Michael E.

    1994-01-01

    The objective of this research project is to characterize by experiment and theoretically both the kinetics of phase separation and the metastable structures produced during phase separation in a microgravity environment. The particular systems we are currently studying are mixtures of water, nonionic surfactants, and compressible supercritical fluids at temperatures and pressures where the coexisting liquid phases have equal densities (isopycnic phases). In this report, we describe experiments to locate equilibrium isopycnic phases and to determine the 'local' phase behavior and critical phenomena at nearby conditions of temperature, pressure, and composition. In addition, we report the results of preliminary small angle neutron scattering (SANS) experiments to characterize microstructures that exist in these mixtures at different fluid densities.

  10. Surfactant-soil interactions during surfactant-amended remediation of contaminated soils by hydrophobic organic compounds: a review.

    Science.gov (United States)

    Laha, Shonali; Tansel, Berrin; Ussawarujikulchai, Achara

    2009-01-01

    Surfactants are amphiphilic molecules that reduce aqueous surface tension and increase the solubility of hydrophobic organic compounds (HOCs). Surfactant-amended remediation of HOC-contaminated soils and aquifers has received significant attention as an effective treatment strategy - similar in concept to using soaps and detergents as washing agents to remove grease from soiled fabrics. The proposed mechanisms involved in surfactant-amended remediation include: lowering of interfacial tension, surfactant solubilization of HOCs, and the phase transfer of HOC from soil-sorbed to pseudo-aqueous phase. However, as with any proposed chemical countermeasures, there is a concern regarding the fate of the added surfactant. This review summarizes the current state of knowledge regarding nonionic micelle-forming surfactant sorption onto soil, and serves as an introduction to research on that topic. Surfactant sorption onto soil appears to increase with increasing surfactant concentration until the onset of micellization. Sorbed-phase surfactant may account for the majority of added surfactant in surfactant-amended remediation applications, and this may result in increased HOC partitioning onto soil until HOC solubilization by micellar phase surfactant successfully competes with increased HOC sorption on surfactant-modified soil. This review provides discussion of equilibrium partitioning theory to account for the distribution of HOCs between soil, aqueous phase, sorbed surfactant, and micellar surfactant phases, as well as recently developed models for surfactant sorption onto soil. HOC partitioning is characterized by apparent soil-water distribution coefficients in the presence of surfactant.

  11. Composition-insensitive highly viscous wormlike micellar solutions formed in anionic and cationic surfactant systems.

    Science.gov (United States)

    Aramaki, Kenji; Iemoto, Suzuka; Ikeda, Naoaki; Saito, Keitaro

    2010-01-01

    We investigated phase behavior and rheological properties of aqueous micellar phase formed in water/cocoyl glutamate neutralized with triethanol amine (CGT-n)/hexadecyl trimethylammonium salt (CTAB or CTAC) systems, where n is a degree of neutralization. Micellar phase appears in wide composition range with respect to the surfactant mixing fraction in ternary phase diagrams at 25 degrees C. At high mixing fraction of cationic surfactant in the water/CGT-n/CTAB systems, one can observe a highly viscous micellar phase in which worm-like micelles are expected to form. Contrary to conventional systems in which worm-like micelles are formed, the zero-shear viscosity of the micellar solution in the water/CGT-n/CTAB system with n=1.2 increases with the addition of cationic cosurfactant and once decreases after a maximum, then increases again and decreases after the second maximum. At n=1.5 and 2, highly viscous solution is observed in the relatively wide range of surfactant mixing fraction instead of two maxima of the viscosity curve observed at n=1.2. In the case of CTAC instead of CTAB we can observe narrow composition range for the maximum viscosity. Frequency sweep measurements were performed on the highly viscous samples in the water/CGT-1.5/CTAB system. Typical viscoelastic behavior of worm-like micellar solutions is observed; i.e. the curves of storage (G') and loss (G") moduli make a crossover and the data points of G' and G" can be fitted to the Maxwell model. Relaxation time against the mixing fraction of two surfactants behaves similarly to the zero-shear viscosity change, whereas the plateau modulus continuously increases in the plateau region for the zero-shear viscosity curve.

  12. Study on the application of nonionic surfactants in detergent%利用生物表面活性剂净化含油污水:菌浓度影响的评估

    Institute of Scientific and Technical Information of China (English)

    A.Khalifeh; B.Roozbehani; A.M.Moradi; S.Imani; M.Mirdrikvand

    2016-01-01

    生物表面活性剂是由微生物产生的可降低界面张力的两亲性化合物。因此,生物表面活性剂可以增加溶质溶解度、生物活性以及有机物的分解速率。本研究采用海洋假单胞菌类分析了生物表面活性剂对原油回收和隔离的作用。生物表面活性剂的制备是在玻璃烧瓶内和实验室条件下完成的。本研究试验了两个pH值范围的四种不同浓度的盐溶液,以期获得打破油包水或水包油乳液将油与水隔离开来的最佳生物表面活性剂浓度。当生物表面活性剂浓度为0.1%时可以达到最好的效果。%Biological decomposition techniques and isolation of environmental polutions using biosurfactants bacteria are effective methods of environmental protection. Surfactants are amphiphilic compounds that are produced by local microorganisms and are able to reduce the surface and the stresses between surfaces. As a result, they wil increase solubility, biological activity, and environmental decomposition of organic compounds. This study analyzes the effects of biosurfactants on crude oil recovery and its isolation using pseudomonas sea bacteria species. Preparation of biosurfactants was done in glass flasks and laboratory conditions. Experiments were carried out to obtain the best concentration of biosurfactants for isolating oil from water and destroying oil-inwater or water-in-oil emulsions in two pH ranges and four saline solutions of different concentrations. The most effective results were gained when a concentration of 0.1% biosurfactants was applied.

  13. COMBINED MICROBIAL SURFACTANT-POLYMER SYSTEM FOR IMPROVED OIL MOBILITY AND CONFORMANCE CONTROL

    Energy Technology Data Exchange (ETDEWEB)

    Jorge Gabitto; Maria Barrufet

    2005-08-01

    Many domestic oil fields are facing abandonment even though they still contain two-thirds of their original oil. A significant number of these fields can yield additional oil using advanced oil recovery (AOR) technologies. To maintain domestic oil production at current levels, AOR technologies are needed that are affordable and can be implemented by the independent oil producers of the future. Microbial enhanced oil recovery (MEOR) technologies have become established as cost-effective solutions for declining oil production. MEOR technologies are affordable for independent producers operating stripper wells and can be used to extend the life of marginal fields. The demonstrated versatility of microorganisms can be used to design advanced microbial systems to treat multiple production problems in complex, heterogeneous reservoirs. The proposed research presents the concept of a combined microbial surfactant-polymer system for advanced oil recovery. The surfactant-polymer system utilizes bacteria that are capable of both biosurfactant production and metabolically-controlled biopolymer production. This novel technology combines complementary mechanisms to extend the life of marginal fields and is applicable to a large number of domestic reservoirs. The research project described in this report was performed by Bio-Engineering Inc., a woman owned small business, Texas A&M University and Prairie View A&M University, a Historically Black College and University. This report describes the results of our laboratory work to grow microbial cultures, the work done on recovery experiments on core rocks, and computer simulations. We have selected two bacterial strains capable of producing both surfactant and polymers. We have conducted laboratory experiments to determine under what conditions surfactants and polymers can be produced from one single strain. We have conduct recovery experiments to determine the performance of these strains under different conditions. Our results

  14. Characterization and evaluation of ionizing and non-ionizing imaging systems used in state of the art image-guided radiation therapy techniques

    Science.gov (United States)

    Stanley, Dennis Nichols

    With the growing incidence of cancer worldwide, the need for effective cancer treatment is paramount. Currently, radiation therapy exists as one of the few effective, non-invasive methods of reducing tumor size and has the capability for the elimination of localized tumors. Radiation therapy utilizes non-invasive external radiation to treat localized cancers but to be effective, physicians must be able to visualize and monitor the internal anatomy and target displacements. Image-Guided Radiation Therapy frequently utilizes planar and volumetric imaging during a course of radiation therapy to improve the precision and accuracy of the delivered treatment to the internal anatomy. Clinically, visualization of the internal anatomy allows physicians to refine the treatment to include as little healthy tissue as possible. This not only increases the effectiveness of treatment by damaging only the tumor but also increases the quality of life for the patient by decreasing the amount of healthy tissue damaged. Image-Guided Radiation Therapy is commonly used to treat tumors in areas of the body that are prone to movement, such as the lungs, liver, and prostate, as well as tumors located close to critical organs and tissues such as the tumors in the brain and spinal cord. Image-Guided Radiation Therapy can utilize both ionizing modalities, like x-ray based planar radiography and cone-beam CT, and nonionizing modalities like MRI, ultrasound and video-based optical scanning systems. Currently ionizing modalities are most commonly utilized for their ability to visualize and monitor internal anatomy but cause an increase to the total dose to the patient. Nonionizing imaging modalities allow frequent/continuous imaging without the increase in dose; however, they are just beginning to be clinically implemented in radiation oncology. With the growing prevalence and variety of Image-Guided Radiation Therapy imaging modalities the ability to evaluate the overall image quality, monitor

  15. Effect of surfactant and surfactant blends on pseudoternary phase diagram behavior of newly synthesized palm kernel oil esters

    Science.gov (United States)

    Mahdi, Elrashid Saleh; Sakeena, Mohamed HF; Abdulkarim, Muthanna F; Abdullah, Ghassan Z; Sattar, Munavvar Abdul; Noor, Azmin Mohd

    2011-01-01

    Background: The purpose of this study was to select appropriate surfactants or blends of surfactants to study the ternary phase diagram behavior of newly introduced palm kernel oil esters. Methods: Nonionic surfactant blends of Tween® and Tween®/Span® series were screened based on their solubilization capacity with water for palm kernel oil esters. Tween® 80 and five blends of Tween® 80/Span® 80 and Tween® 80/Span® 85 in the hydrophilic-lipophilic balance (HLB) value range of 10.7–14.0 were selected to study the phase diagram behavior of palm kernel oil esters using the water titration method at room temperature. Results: High solubilization capacity was obtained by Tween® 80 compared with other surfactants of Tween® series. High HLB blends of Tween® 80/Span® 85 and Tween® 80/Span® 80 at HLB 13.7 and 13.9, respectively, have better solubilization capacity compared with the lower HLB values of Tween® 80/Span® 80. All the selected blends of surfactants were formed as water-in-oil microemulsions, and other dispersion systems varied in size and geometrical layout in the triangles. The high solubilization capacity and larger areas of the water-in-oil microemulsion systems were due to the structural similarity between the lipophilic tail of Tween® 80 and the oleyl group of the palm kernel oil esters. Conclusion: This study suggests that the phase diagram behavior of palm kernel oil esters, water, and nonionic surfactants is not only affected by the HLB value, but also by the structural similarity between palm kernel oil esters and the surfactant used. The information gathered in this study is useful for researchers and manufacturers interested in using palm kernel oil esters in pharmaceutical and cosmetic preparation. The use of palm kernel oil esters can improve drug delivery and reduce the cost of cosmetics. PMID:21792294

  16. Triblock Copolymers with Grafted Fluorine-Free Amphiphilic Non-Ionic Side Chains for Antifouling and Fouling-Release Applications

    Energy Technology Data Exchange (ETDEWEB)

    Y Cho; H Sundaram; C Weinman; M Paik; M Dimitriou; J Finlay; M Callow; J Callow; E Kramer; C Ober

    2011-12-31

    Fluorine-free, amphiphilic, nonionic surface active block copolymers (SABCs) were synthesized through chemical modification of a polystyrene-block-poly(ethylene-ran-butylene)-block-polyisoprene triblock copolymer precursor with selected amphiphilic nonionic Brij and other surfactants. Amphiphilicity was imparted by a hydrophobic aliphatic group combined with a hydrophilic poly(ethylene glycol) (PEG) group-containing moiety. The surfaces were characterized by dynamic water contact angle, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and near edge X-ray absorption fine structure (NEXAFS) analysis. In biofouling assays, settlement (attachment) of both spores of the green alga Ulva and cells of the diatom Navicula on SABCs modified with Brij nonionic side chains was significantly reduced relative to a PDMS standard, with a nonionic surfactant combining a PEG group and an aliphatic moiety demonstrating the best performance. Additionally, a fouling-release assay using sporelings (young plants) of Ulva and Navicula suggested that the SABC derived from nonionic Brij side chains also out-performed PDMS as a fouling-release material. Good antifouling and fouling-release properties were not demonstrated for the other two amphiphilic surfaces derived from silicone and aromatic group containing nonionic surfactants included in this study. The results suggest that small differences in chemical surface functionality impart more significant changes with respect to the antifouling settlement and fouling-release performance of materials than overall wettability behavior.

  17. Transformation of Vesicles in Aqueous Two-Phase System of an Anionic Gemini Surfactant and a Cationic Conventional Surfactant Mixture

    Institute of Scientific and Technical Information of China (English)

    JIANG Rong; HUANG Yi-Xiong; ZHAO Jian-Xi; HUANG Chang-Cang

    2008-01-01

    Transformation of vesicles formed in DTAB/C11-p-PhCNa aqueous surfactant two-phase (ASTP) was observed by the transmission electron microscopy (TEM). The trans-conformation of the gemini surfactant in the aggregates was considered to be the important factor for constructing the multi-lamellar structure of the vesicle wall. The cation-π interaction between the quaternary ammonium cation and the aromatic ring in the spacer was determined by the UV-Vis spectrum analysis, which, as well as the general electrostatic attraction and hydrophobic force, contributes to the stability of the multi-lamellar structure. The concentrations of the surface-active ions were measured for understanding the mechanism of vesicle transformation. The results show that isoelectric mixing of the two components benefits the growth of vesicles both in size and wall thickness.

  18. Pressure-induced structural transition of nonionic micelles

    Indian Academy of Sciences (India)

    V K Aswal; R Vavrin; J Kohlbrecher; A G Wagh

    2008-11-01

    We report dynamic light scattering and small angle neutron scattering studies of the pressure-induced structural transition of nonionic micelles of surfactant polyoxyethylene 10 lauryl ether (C12E10) in the pressure range 0 to 2000 bar. Measurements have been performed on 1 wt% C12E10 in aqueous solution with and without the addition of KF. Micelles undergo sphere to lamellar structural transitions as the pressure is increased. On addition of KF, rod-like micelles exist at ambient pressure, which results in rod-like to lamellar structural transition at a much lower pressure in the presence of KF. Micellar structural transitions have been observed to be reversible.

  19. Surfactants, not size or zeta-potential influence blood-brain barrier passage of polymeric nanoparticles.

    Science.gov (United States)

    Voigt, Nadine; Henrich-Noack, Petra; Kockentiedt, Sarah; Hintz, Werner; Tomas, Jürgen; Sabel, Bernhard A

    2014-05-01

    Nanoparticles (NP) can deliver drugs across the blood-brain barrier (BBB), but little is known which of the factors surfactant, size and zeta-potential are essential for allowing BBB passage. To this end we designed purpose-built fluorescent polybutylcyanoacrylate (PBCA) NP and imaged the NP's passage over the blood-retina barrier - which is a model of the BBB - in live animals. Rats received intravenous injections of fluorescent PBCA-NP fabricated by mini-emulsion polymerisation to obtain various NP's compositions that varied in surfactants (non-ionic, anionic, cationic), size (67-464nm) and zeta-potential. Real-time imaging of retinal blood vessels and retinal tissue was carried out with in vivo confocal neuroimaging (ICON) before, during and after NP's injection. Successful BBB passage with subsequent cellular labelling was achieved if NP were fabricated with non-ionic surfactants or cationic stabilizers but not when anionic compounds were added. NP's size and charge had no influence on BBB passage and cell labelling. This transport was not caused by an unspecific opening of the BBB because control experiments with injections of unlabelled NP and fluorescent dye (to test a "door-opener" effect) did not lead to parenchymal labelling. Thus, neither NP's size nor chemo-electric charge, but particle surface is the key factor determining BBB passage. This result has important implications for NP engineering in medicine: depending on the surfactant, NP can serve one of two opposite functions: while non-ionic tensides enhance brain up-take, addition of anionic tensides prevents it. NP can now be designed to specifically enhance drug delivery to the brain or, alternatively, to prevent brain penetration so to reduce unwanted psychoactive effects of drugs or prevent environmental nanoparticles from entering tissue of the central nervous system.

  20. Competitive adsorption from mixed hen egg-white lysozyme/surfactant solutions at the air-water interface studied by tensiometry, ellipsometry, and surface dilational rheology.

    Science.gov (United States)

    Alahverdjieva, V S; Grigoriev, D O; Fainerman, V B; Aksenenko, E V; Miller, R; Möhwald, H

    2008-02-21

    The competitive adsorption at the air-water interface from mixed adsorption layers of hen egg-white lysozyme with a non-ionic surfactant (C10DMPO) was studied and compared to the mixture with an ionic surfactant (SDS) using bubble and drop shape analysis tensiometry, ellipsometry, and surface dilational rheology. The set of equilibrium and kinetic data of the mixed solutions is described by a thermodynamic model developed recently. The theoretical description of the mixed system is based on the model parameters for the individual components.

  1. Removal of 226Ra and 228Ra from TENORM sludge waste using surfactants solutions.

    Science.gov (United States)

    Attallah, M F; Hamed, Mostafa M; El Afifi, E M; Aly, H F

    2015-01-01

    The feasibility of using surfactants as extracting agent for the removal of radium species from TENORM sludge produced from petroleum industry is evaluated. In this investigation cationic and nonionic surfactants were used as extracting agents for the removal of radium radionuclides from the sludge waste. Two surfactants namely cetyltrimethylammonium bromide (CTAB) and Triton X-100 (TX100) were investigated as the extracting agents. Different parameters affecting the removal of both (226)Ra and (228)Ra by the two surfactants as well as their admixture were studied by the batch technique. These parameters include effect of shaking time, surfactants concentration and temperature as well as the effect of surfactants admixture. It was found that, higher solution temperature improves the removal efficiency of radium species. Combined extraction of nonionic and cationic surfactants produces synergistic effect in removal both (226)Ra and (228)Ra, where the removals reached 84% and 80% for (226)Ra and (228)Ra, respectively, were obtained using surfactants admixture.

  2. MICELLAR PARAMETERS OF DIBLOCK COPOLYMERS AND THEIR INTERACTIONS WITH IONIC SURFACTANTS

    Institute of Scientific and Technical Information of China (English)

    Noor Rehman; Abbas Khan; Iram Bibi; Mohammad Siddiq

    2012-01-01

    The interactions of non-ionic amphiphilic diblock copolymer poly(oxyethylene/oxybutylene) (E39B18) with anionic surfactant sodium dodecyl sulphate (SDS) and cationic surfactant hexadecyltrimethylammonium bromide (CTAB) were studied by using various techniques such as surface tension,conductivity,steady-state fluorescence and dynamic light scattering.Surface tension measurements were used to determine the critical micelle concentration (CMC) and thereby the free energy of micellization (AGmic),free energy of adsorption (AGads),surface excess concentration (F) and minimum area per molecule (A).Conductivity measurements were used to determine the critical micelle concentration (CMC),critical aggregation concentration (CAC),polymer saturation point (PSP),degree of ionization (α) and counter ion binding (β).Dynamic light scattering experiments were performed to check the changes in physiochemical properties of the block copolymer micelles taken place due to the interactions of diblock copolymers with ionic surfactants.The ratio of the first and third vibronic peaks (I1/I13) indicated the polarity of the pyrene micro environment and was used for the detection of micelle as well as polymer-surfactant interactions.Aggregation number (N),number of binding sites (n) and free energy of binding (AGb) for pure surfactants as well as for polymer-surfactant mixed micellar systems were determined by the fluorescence quenching method.

  3. Self-association of short-chain nonionic amphiphiles in binary and ternary systems: comparison between the cleavable ethylene glycol monobutyrate and its ether counterparts.

    Science.gov (United States)

    Zhu, Ying; Fournial, Anne-Gaëlle; Molinier, Valérie; Azaroual, Nathalie; Vermeersch, Gaston; Aubry, Jean-Marie

    2009-01-20

    In the context of environmental concerns for the production of surface active species, the introduction of a carbonyl function into the skeleton of ethyleneglycol-derived solvo-surfactants is a way to access cleavable compounds with presumed enhanced biodegradability. Ethylene glycol monobutyrate (C(3)COE(1)) was synthesized and compared to its ether counterparts, ethylene glycol monopropyl (C(3)E(1)) and monobutyl ethers (C(4)E(1)), to assess the effect of the insertion of a carbonyl function in the skeleton of short-chain ethoxylated amphiphilic compounds. In aqueous solutions, the ester has intermediate behavior between that of the two ethers with regard to surface tension, solubilization of Me-naphtalene in water, and self-diffusion by PGSE NMR. In ternary systems, C(3)COE(1) and C(3)E(1) have the same optimal oil (EACN = 2.8), which is much more polar than that of C(4)E(1) (EACN = 8.5). With regard to the ability to form structured systems, the behavior in water does not differ significantly for the three compounds, and the transition between nonassociating solvents and amphiphilic solvents, sometimes called solvo-surfactants, is gradual. In ternary systems, however, only C(4)E(1) and C(3)COE(1) form a third phase near the optimal formulation, which tends to show that C(3)COE(1) possesses the minimum amphiphilicity to get a structuration. Self-diffusion NMR studies of the one-phase domains do not, however, allow us to distinguish between different degrees of organization in the three systems.

  4. Curing kinetics and morphology of a nanovesicular epoxy/stearyl-block-poly(ethylene oxide) surfactant system.

    Science.gov (United States)

    Bogaerts, K; Lavrenova, A; Spoelstra, A B; Boyard, N; Goderis, B

    2015-08-21

    Brittle epoxy based thermosets can be made tougher by introducing structural inhomogeneities at the micro- or nanoscale. In that respect, nano vesicles and worm-like micelles from self-assembling blockcopolymers have been shown to be very effective. This paper describes the curing kinetics and morphology of an epoxy composed of diglycidyl ether of bisphenol A (DGEBA) and 4,4'-methylenedianiline (MDA), modified by 20% of the surfactant stearyl-block-poly(ethylene oxide). Time resolved, synchrotron small-angle X-ray scattering demonstrates that at any time during the epoxy curing process, the surfactant predominantly adopts a bilayer vesicular nano-morphology. Transmission electron microscopy on fully cured systems reveals the coexistence of spherical and worm-like micelles. Differential scanning calorimetry experiments prove that the presence of surfactant reduces the epoxy curing rate but that ultimately full curing is accomplished. The material glass transition temperature falls below that of the pure resin due to plasticization. It is suggested that favorable secondary interactions between the PEO segments and the epoxy resin are responsible for the observed phenomena.

  5. Change Color Effect and Spectral Properties of Gold Nanoparticle-cationic Surfactants System

    Institute of Scientific and Technical Information of China (English)

    JIANG Zhi-liang; PAN Hong-cheng; YUAN Wei-en

    2004-01-01

    The change color effect of gold nanoparticle solutions was studied by means of resonance scattering and absorption spectrometry and scan electron microscopy. The red Au nanoparticles with a size of 10 nm exhibit a resonance absorption peak and a resonance scattering peak all at 525 nm. After some inorganic electrolyte was added to a red Au nanoparticles solution, the color of the solution became blue and the absorbance at 600-700 nm was significantly increased. The ratio of the concentration of monovalent cations, at which the resonance scattering of the system at 525 nm is maximal to that of divalent cations, is in the range of 100 : 1 -100 : 1.8. It is in good agreement with the Schulze-Hardy rule of the coagulation value of electrolyte. After adding some cationic surfactants to the above solution, the color of the solution is in deep blue, with two resonance absorption peaks at 550 and 680 nm, and a greatly enhanced resonance scattering peak at 525 nm.The experiments demonstrate that the stronger the hydrophobicity of the cationic surfactant is, the stronger the change color effect of the Au nanoparticle solution promoted by cationic surfactant is. The change color effect of Au nanoparticle solution is resulted from the increased diameter of Au nanoparticles, and the changes of resonance absorption peak and resonance scattering.

  6. Effect of added surfactant on interfacial tension and spontaneous emulsification in alkali/acidic oil systems

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, J.; Bernard, C.; Wasan, D.T. (Illinois Inst. of Tech., Chicago, IL (United States). Dept. of Chemical Engineering)

    1994-05-01

    An experimental investigation of the buffered surfactant-enhanced alkaline flooding system chemistry was undertaken to determine the influence of various species present on interfacial tension as a function of pH and ionic strength. Phase behavior tests that monitor the extent of emulsification are sufficient to determine the region of low interfacial tension. Optimization of interfacial tension by adjustment of the ionic strength alone may not necessarily provide the lowest interfacial tension under the best conditions. The pH should be simultaneously optimized along with ionic strength to allow better control over attainment of low interfacial tension. The dominant mechanism by which added surfactant aids in the reduction of interfacial tension is the formation of mixed micelles with the ionized acid. Although added surfactant partitioning from the influence of the un-ionized acid and ionic strength will affect interfacial behavior, the formation of mixed micelles plays a dominant role. Middle-phase formation is possible with a low acid oil using a petroleum sulfonate at a proper pH and ionic strength.

  7. Emerging dynamics in surfactant-based liquid mixtures: Octanoic acid/bis(2-ethylhexyl) amine systems

    Science.gov (United States)

    Calandra, Pietro; Mandanici, Andrea; Turco Liveri, Vincenzo; Pochylski, Mikolaj; Aliotta, Francesco

    2012-02-01

    This work focuses on the dynamic phenomena emerging in self-assembled transient intermolecular networks formed when two different surfactants are mixed. In particular, the relaxation processes in liquid mixtures composed by bis(2-ethylhexyl)amine (BEEA) and octanoic acid (OA) in the whole composition range has been investigated by dielectric spectroscopy and Brillouin spectroscopy. A thorough analysis of all the experimental data consistently suggests that, mainly driven by acid-base interactions arising when the two surfactants are mixed, supra-molecular aggregates formation causes the slowing down of molecular dynamics. This, in turn, reflects to longer-range relaxations. These changes have been found to be composition-dependent, involving strong departures of the mixture physico-chemical properties from an ideal behaviour, and reflecting the structural and dynamical features of local structures. In particular, the peculiar dynamic processes occurring in these local inter-molecular structures, have been found to be the factors responsible for the observed and quite surprising increase of direct-current conductivity which occurs when two different (and pretty non-conductive) surfactants are mixed. The discovery can be used not only to design novel materials for application purposes but also to shed more light on the basic principles regulating charge migration in structured liquid systems.

  8. Constrained sessile drop as a new configuration to measure low surface tension in lung surfactant systems.

    Science.gov (United States)

    Yu, Laura M Y; Lu, James J; Chan, Yawen W; Ng, Amy; Zhang, Ling; Hoorfar, Mina; Policova, Zdenka; Grundke, Karina; Neumann, A Wilhelm

    2004-08-01

    Existing methodology for surface tension measurements based on drop shapes suffers from the shortcoming that it is not capable to function at very low surface tension if the liquid dispersion is opaque, such as therapeutic lung surfactants at clinically relevant concentrations. The novel configuration proposed here removes the two big restrictions, i.e., the film leakage problem that is encountered with such methods as the pulsating bubble surfactometer as well as the pendant drop arrangement, and the problem of the opaqueness of the liquid, as in the original captive bubble arrangement. A sharp knife edge is the key design feature in the constrained sessile drop that avoids film leakage at low surface tension. The use of the constrained sessile drop configuration in conjunction with axisymmetric drop shape analysis to measure surface tension allows complete automation of the setup. Dynamic studies with lung surfactant can be performed readily by changing the volume of a sessile drop, and thus the surface area, by means of a motor-driven syringe. To illustrate the validity of using this configuration, experiments were performed using an exogenous lung surfactant preparation, bovine lipid extract surfactant (BLES) at 5.0 mg/ml. A comparison of results obtained for BLES at low concentration between the constrained sessile drop and captive bubble arrangement shows excellent agreement between the two approaches. When the surface area of the BLES film (0.5 mg/ml) was compressed by about the same amount in both systems, the minimum surface tensions attained were identical within the 95% confidence limits.

  9. Tunable, antibacterial activity of silicone polyether surfactants.

    Science.gov (United States)

    Khan, Madiha F; Zepeda-Velazquez, Laura; Brook, Michael A

    2015-08-01

    Silicone surfactants are used in a variety of applications, however, limited data is available on the relationship between surfactant structure and biological activity. A series of seven nonionic, silicone polyether surfactants with known structures was tested for in vitro antibacterial activity against Escherichia coli BL21. The compounds varied in their hydrophobic head, comprised of branched silicone structures with 3-10 siloxane linkages and, in two cases, phenyl substitution, and hydrophilic tail of 8-44 poly(ethylene glycol) units. The surfactants were tested at three concentrations: below, at, and above their Critical Micelle Concentrations (CMC) against 5 concentrations of E. coli BL21 in a three-step assay comprised of a 14-24h turbidometric screen, a live-dead stain and viable colony counts. The bacterial concentration had little effect on antibacterial activity. For most of the surfactants, antibacterial activity was higher at concentrations above the CMC. Surfactants with smaller silicone head groups had as much as 4 times the bioactivity of surfactants with larger groups, with the smallest hydrophobe exhibiting potency equivalent to sodium dodecyl sulfate (SDS). Smaller PEG chains were similarly associated with higher potency. These data link lower micelle stability and enhanced permeability of smaller silicone head groups to antibacterial activity. The results demonstrate that simple manipulation of nonionic silicone polyether structure leads to significant changes in antibacterial activity.

  10. Aqueous foam surfactants for geothermal drilling fluids: 1. Screening

    Energy Technology Data Exchange (ETDEWEB)

    Rand, P.B.

    1980-01-01

    Aqueous foam is a promising drilling fluid for geothermal wells because it will minimize damage to the producing formation and would eliminate the erosion problems of air drilling. Successful use of aqueous foam will require a high foaming surfactant which will: (1) be chemically stable in the harsh thermal and chemical environment, and (2) form stable foams at high temperatures and pressures. The procedures developed to generate and test aqueous foams and the effects of a 260/sup 0/C temperature cycle on aqueous surfactant solutions are presented. More than fifty selected surfactants were evaluated with representatives from the amphoteric, anionic, cationic, and nonionic classes included. Most surfactants were severely degraded by this temperature cycle; however, some showed excellent retention of their properties. The most promising surfactant types were the alkyl and alkyl aryl sulfonates and the ethoxylated nonionics.

  11. Thermal Diffusion in binary Surfactant Systems and Microemulsions

    OpenAIRE

    Arlt, B.

    2012-01-01

    In dieser Arbeit haben wir das Thermodiffusionsverhalten von mizellaren Systemen und Mikroemulsionen untersucht. Beide Systeme werden als Modellsysteme genutzt um zwei Fragestellungen zu beantworten. Die erste Fragestellung bezieht sich auf den Einfluss der Mizellenbildung nahe der kritischen Mizellenkonzentration (cmc) auf das Thermodiffusionsverhalten. Dazu untersuchen wir das Thermodiffusionsverhalten des nichtionischen Tensides n-Octyl beta-D-Glucopyranoside (C8G1) in Wasser, welches e...

  12. [The role of individual stress resistance in realization of immobilization and zoosocial stress effects on pulmonary surfactant system].

    Science.gov (United States)

    Vasil'eva, N N; Bryndina, I G

    2012-07-01

    The aim of the present study was to investigate the effect of chronic exposure to immobilization and psychosocial stress on surface activity, biochemical composition of pulmonary surfactant and lung fluid balance of rats with different stress-resistance. It is shown that both types of stress lead to elevation of lysophospholipids level and decrease of surface-active properties of pulmonary surfactant, more prominent in stress-vulnerable rats. Blood supply was decreased and extravascular fluid was increased under the psychosocial stress only in stress-vulnerable animals, in all rest cases the blood supply was increased and the content of extravascular fluid was not changed. Surfactant alteration was coupled on the level of 11-OCS in the blood and amount of fluid in the lungs. The obtained results indicate that different degree of impairment in the pulmonary surfactant system during immobilization and psychosocial conflicts depends on different resistance to emotional stress.

  13. An amine-oxide surfactant-based microemulsion for the cleaning of works of art.

    Science.gov (United States)

    Baglioni, Michele; Jàidar Benavides, Yareli; Berti, Debora; Giorgi, Rodorico; Keiderling, Uwe; Baglioni, Piero

    2015-02-15

    Surfactant-based aqueous fluids, such as micellar solutions and microemulsions, are effective, safe and selective media for cleaning operations in conservation of cultural heritage. The search for better-performing systems and eco-friendly cleaning systems is currently a major goal in conservation science. We report here on a ternary o/w microemulsion, composed of diethyl carbonate (DC) as the oil phase and N,N-Dimethyldodecan-1-amine oxide (DDAO) as the surfactant. DDAO is a well known and widely used detergent and solubilizing agent, selected here for its degradability and eco-compatibility. Due to its nonionic/cationic nature, it can be used also when nonionic-based formulations become ineffective because of clouding and phase separation. Moreover, DDAO is insensitive to the presence of divalent metal ions, usually abundant in wall paintings substrates. Small-Angle Neutron Scattering (SANS) provided detailed information about the nanostructure of the surfactant aggregates. Finally, the cleaning effectiveness of the nanofluid was assessed both on fresco mock-ups and on real wall paintings conserved in the archeological site of Tulum, Mexico. Here, conservators successfully used the microemulsion to remove naturally aged films of complex polymer mixtures from the works of art surface. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Interfacial behaviour between oil/water systems using ionic surfactants from regional vegetable industry and animal pet

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Francisco Klebson G.; Alves, Juan V.A.; Dantas, Tereza N. Castro; Dutra Junior, Tarcilio V.; Barros Neto, Eduardo L. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil)

    2008-07-01

    Interfacial tension (IFT) is one of the most important physical properties in the study of fluid-fluid interfaces. In this research the surfactants - saponified coconut oil, saponified castor oil, saponified soybean oil, saponified sunflower oil and basis soap - were synthesized in laboratory, using carboxylic acids from regional industry and animal fat (bovine fat). This study focuses on the search of a high-efficient, low-cost, and safe for the environment flooding system to be applied in enhanced oil recovery. The principal aim of this work is the obtaining of interfacial tensions between oil/water systems, using the developed ionic surfactants. Results showed that the studied surfactants are able to reduce the IFT between oil and brine. The surfactant that was more effective in reducing the IFT value was the one from animal fat. The composition, as well as the kind of the bond, as saturated or unsaturated, of the surfactants has influence in the IFT value. The ionic surfactants from regional industry and animal fat besides presenting low cost propitiate very low interfacial tensions between oil and brine, favoring the interactions with residual oil and thus increasing oil recovery. (author)

  15. Rheological Properties of the Aqueous Solution for Fluorocarbon-containing Hydrophobically Modified Sodium PolyacrylicAcid with Various Surfactants

    Institute of Scientific and Technical Information of China (English)

    GUO,Jin-Feng(郭金峰); ZHUANG,Dong-Qing(庄东青); ZHOU,Hui(周晖); ZHANG,Yun-Xiang(章云祥)

    2001-01-01

    The interaction of fluorocarbon-containing hydrophobicallymodified sodiun polyacryiic acid (FMPAANa) (0.5 wt% )with various surfactants (anionic,nonionic and cationic) hasbeen investigated by theological measurements.Different rhe-ological behaviors are displayed for ionic surfactants and non-ionic surfactants.Fluorinated surfactants have stronger affini-ty with polyelectrolyte hydrophobes comparing with hydro-genated surfactants.The hydrophobic association of FM-PAANa with a cationic surfactant (CTAB) and a fluorinatednonionic surfactant (FC171) is much stronger than with anonionic surfactant (NP7.5 ) and an anionic surfactant(FC143).Further investigation of the effects of temperatureon solution properties shows that the dissociation energy Em iscorrelated to the strength of the aggregated junctions.``

  16. Preparation and Photocatalytic Property of ZnO Nanoparticles via Non-Ionic Surfactant Dodecylamine Assisted Hydrothermal Method%非离子表面活性剂十二胺辅助水热合成氧化锌纳米粉体及其光催化性能研究

    Institute of Scientific and Technical Information of China (English)

    陈婷; 徐彦乔; 江莞; 江伟辉; 谢志翔

    2016-01-01

    Zinc oxide nanoparticles were prepared via hydrothermal method at 160℃for 24 h using zinc chloride as raw material, ammonia as alkali source and non-ionic surfactant dodecylamine (DDA) as template, respectively. The phase of the resulting product was investigated by X-ray diffraction (XRD), while the morphology and microstructure were characterized by ifeld emission scanning electron microscope (FESEM) and high resolution transmission electron microscopy (HRTEM), respectively. The experimental results show that all the samples are pure zinc oxides with hexagonal wurtzite structure. The samples in the absence of DDA were nanorods with 2-10μm in length and 0.5-0.8 μm in diameter. Increasing the DDA amount, the homogeneity of the samples is increased, and the morphology was changed from nanorods to nanoparticles with the particle size about 80-100 nm. The nanoparticles exhibited excellent photocatalytic ability at room temperature. After 120 min irradiation, the degradation degree of 10 mg/L Congo red dye was close to 100%.%以氯化锌为原料、氨水为碱源,添加非离子表面活性剂十二胺(DDA)为模板剂经160℃水热24 h制备了氧化锌纳米粉体。通过X射线衍射(XRD)分析了产物的组成结构,并采用场发射扫描电子显微镜(FESEM)和高分辨透射电子显微镜(HRTEM)对样品的显微形貌进行了表征。实验结果表明,制备的样品为六方纤锌矿结构的氧化锌。在不添加DDA的条件下,水热产物为长2-10μm、直径0.5-0.8μm的一维纳米棒;随着DDA添加量的增大,样品的均匀性提高,同时由纳米棒转变为纳米颗粒,粒径大小为80-100 nm。室温下该纳米颗粒具有优异的光催化性能,在光照240 min后对质量浓度为10 mg/L的刚果红的降解率达到100%。

  17. Dendrimer-surfactant interactions.

    Science.gov (United States)

    Cheng, Yiyun; Zhao, Libo; Li, Tianfu

    2014-04-28

    In this article, we reviewed the interactions between dendrimers and surfactants with particular focus on the interaction mechanisms and physicochemical properties of the yielding dendrimer-surfactant aggregates. In order to provide insight into the behavior of dendrimers in biological systems, the interactions of dendrimers with bio-surfactants such as phospholipids in bulk solutions, in solid-supported bilayers and at the interface of phases or solid-states were discussed. Applications of the dendrimer-surfactant aggregates as templates to guide the synthesis of nanoparticles and in drug or gene delivery were also mentioned.

  18. Performance of the Biocompatible Surfactant Tween 80, for the Formation of Microemulsions Suitable for New Pharmaceutical Processing

    Directory of Open Access Journals (Sweden)

    Cristina Prieto

    2013-01-01

    Full Text Available The aim of this work was to investigate the phase behaviour and the structure of the n-hexane/water emulsions based on a nonionic, nontoxic and biocompatible surfactant, Tween 80. This system is of interest for new pharmaceutical techniques based on supercritical fluids to form nano- and encapsulated particles. However, it showed a lack of stability denoted by large areas of macroemulsion. For this reason, the effect of additives (alcohols and brine and external variables (temperature were explored. The replacement of water by brine caused negligible impact due to the nonionic character of Tween 80. On the contrary, the presence of an alcohol (ethanol or 1-butanol enhanced the solubility of the surfactant in the oil phase and decreased the mixture viscosity, resulting in improved surface activity. Similar results were obtained by raising the temperature until the cloud point was reached (60°C. With these modifications, microemulsions at relatively low concentrations of surfactant (around 30% and within a broad interval of compositions could be obtained, widening their possible use in pharmaceuticals manufacturing (such as controlled drug delivery, enzymatic reactions, or excipient processing. The understanding of the surfactant performance could be further used to substitute the n-hexane by a greener solvent, such as supercritical CO2.

  19. Molecular Dynamics Study of the Foam Stability of a Mixed Surfactant System with and without Calcium Ions

    Science.gov (United States)

    Yang, Xiaozhen; Yang, Wenhong; Institute of Chemistry, CAS Team

    2011-03-01

    Foam stability performance of a mixture surfactant system with and without calcium ions, including linear alkylbenzene sulfonate (LAS) and sodium dodecyl sulfate (SDS), has been studied by molecular dynamics. Microscopic interaction analysis reveals that the fraction of free calcium ions, Xf , in film system indicates the extent of the foam stabilities when Xf is in different calcium ion zones. In the system without ions, we found the variable of the surfactant tail mass out of water film, W , is indicator of foam stability. Performance of the mixture system predicted here was supported by experiments.

  20. Pulmonary surfactant adsorption is increased by hyaluronan or polyethylene glycol.

    Science.gov (United States)

    Taeusch, H William; Dybbro, Eric; Lu, Karen W

    2008-04-01

    In acute lung injuries, inactivating agents may interfere with transfer (adsorption) of pulmonary surfactants to the interface between air and the aqueous layer that coats the interior of alveoli. Some ionic and nonionic polymers reduce surfactant inactivation in vitro and in vivo. In this study, we tested directly whether an ionic polymer, hyaluronan, or a nonionic polymer, polyethylene glycol, enhanced adsorption of a surfactant used clinically. We used three different methods of measuring adsorption in vitro: a modified pulsating bubble surfactometer; a King/Clements device; and a spreading trough. In addition we measured the effects of both polymers on surfactant turbidity, using this assay as a nonspecific index of aggregation. We found that both hyaluronan and polyethylene glycol significantly increased the rate and degree of surfactant material adsorbed to the surface in all three assays. Hyaluronan was effective in lower concentrations (20-fold) than polyethylene glycol and, unlike polyethylene glycol, hyaluronan did not increase apparent aggregation of surfactant. Surfactant adsorption in the presence of serum was also enhanced by both polymers regardless of whether hyaluronan or polyethylene glycol was included with serum in the subphase or added to the surfactant applied to the surface. Therefore, endogenous polymers in the alveolar subphase, or exogenous polymers added to surfactant used as therapy, may both be important for reducing inactivation of surfactant that occurs with various lung injuries.

  1. Partitioning of hexachlorobenzene in a kaolin/humic acid/surfactant/water system: combined effect of surfactant and soil organic matter.

    Science.gov (United States)

    Wan, Jinzhong; Wang, Lingling; Lu, Xiaohua; Lin, Yusuo; Zhang, Shengtian

    2011-11-30

    Understanding the combined effect of soil organic matter (SOM) and surfactants on the partitioning of hydrophobic organic compounds in soil/water systems is important to predict the effectiveness of surfactant-enhanced remediation (SER). In the present study we investigate the partitioning of hexachlorobenzene (HCB) within a humic acid (HA)-coated kaolin/Triton X-100 (TX100)/water system, with special emphasis on the interaction between TX100 and HA, and their combined effect on HCB sorption. HA firstly enhanced then suppressed TX100 sorption to kaolin as the amounts of HA increased, while the addition of TX100 led to a consistent reduction in HA sorption. In the HA-coated kaolin/TX100/water system, TX100 played a primary role in enhancing desorption of HCB, while the role could be suppressed and then enhanced as HA coating amounts increased. Only at HA coating above 2.4%, dissolved HA outcompeted clay-bound HA for HCB partitioning, resulting in dissolved HA enhanced desorption. The presence of dissolved HA at these conditions further promoted the effectiveness of TX100 enhanced desorption. Despite a reduced TX100 sorption to clay was achieved due to the presence of dissolved HA, the effect on HCB desorption was comparatively slight. A reliable cumulative influence of HA and TX100 on HCB desorption was observed, although HCB desorption by HA/TX100 mixed was less than the sum of HA and TX100 individually. Our study suggests that for soils of high organic contents, the combined effect of SOM and surfactants on HOCs desorption can be applied to improve the performance of SER. Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Dynamic covalent surfactants

    NARCIS (Netherlands)

    Minkenberg, C.B.

    2012-01-01

    In this thesis the development of surfactant aggregates with fast exchange dynamics between the aggregated and non-aggregated state is described. Dynamic surfactant exchange plays an important role in natural systems, for instance in cell signaling, cell division, and uptake and release of cargo. Re

  3. The hydrophobicity of silicone-based oils and surfactants and their use in reactive microemulsions.

    Science.gov (United States)

    Castellino, Victor; Cheng, Yu-Ling; Acosta, Edgar

    2011-01-01

    In this work, for the first time, the Hydrophilic-Lipophilic Difference (HLD) framework for microemulsion formulation has been applied to silicone oils and silicone alkyl polyether surfactants. Based on the HLD equations and recently introduced mixing rules, we have quantified the hydrophobicity of the oils according to the equivalent alkane carbon number (EACN). We have found that, in a reference system containing sodium dihexyl sulfosuccinate (SDHS) as the surfactant, 0.65 centistoke (cSt) and 3.0 cSt silicone oils behave like n-dodecane and n-pentadecane, respectively. Silicone alkyl polyether surfactants were found to have characteristic curvatures ranging 3.4-18.9, exceeding that of most non-ionic surfactants. The introduction of methacrylic acid (MAA) and hydroxyethyl methacrylate (HEMA) to the aqueous phase caused a significant negative shift in HLD, indicative of an aqueous phase that is less hydrophilic than pure water. The more hydrophobic surfactants (largest positive curvatures) were used in order to compensate for this effect. These findings have led to the formulation of bicontinuous microemulsions (μEs) containing silicone oil, silicone alkyl polyether and reactive monomers in aqueous solution. Ternary phase diagrams of these systems revealed the potential for silicone-containing polymer composites with bicontinuous morphologies. These findings have also helped to explain the phase behavior of formulations previously reported in literature, and could help in providing a systematic, consistent approach to future silicone oil based microemulsion formulation.

  4. Hydrophobically Modified Polyelectrolytes: V. Interaction of Fluorocarbon Modified Poly (acrylic acid) with Various Added Surfactants

    Institute of Scientific and Technical Information of China (English)

    ZHOU,Hui(周晖); SONG,Guo-Qaiang(宋国强); GUO,Jin-Feng(郭金峰); ZHANG,Yun-xiang (章云祥); DIEING,Reinhold; MA,Lian(马莲); HAEUSSLING,Lukas

    2001-01-01

    The interactions between fiuorocarbon-medified pol(sodium acrylate) and various kinds of added surfactant have been studied by means of viscometric measurement. Association behavior was found in both hydrogenated and fluorinated anionic, nonionic and cationic surfactants. Among them, the interactions between fluorocarbon-modified poly ( sodium acrylate) and cationic surfactants are the strongest, owing to the cooperation of both electrostatic attractions and hydrophobic associations. The anionic surfactants have the weakest effects on the solution properties because of the existence of unfavorable electrostatic repulsion. The hydrophobic interactions between copolymers and fluorinated surfactants are much stronger than those between copolymers and hydrogenated surfactants.

  5. The synthesis of quantum size lead sulfide particles in surfactant-based complex fluid media

    Energy Technology Data Exchange (ETDEWEB)

    Ward, A.J.I.; O' Sullivan, E.C.; Rang, Jing Chen; Nedeljkovic, J.; Patel, R.C. (Clarkson Univ., Potsdam, NY (United States). Dept. of Chemistry)

    1993-12-01

    The relative roles of the ion interactions, molecular complex formation, and the local structure of the medium on the formation of nano-sized particles of lead sulfide (PbS) in a nonionic surfactant/water/oil microemulsion have been investigated. Comparison of the reaction carried out under conditions of minimal hydrolysis of the cation (low pH) in two different counterion/acid systems (nitric or perchlorate) indicates that hydrolysis does not play a significant role in the production of PbS in fine particle form. Furthermore, the nature of tile counterion, NO[sub 3][sup [minus

  6. Effect of ionic surfactants on the phase behavior and structure of sucrose ester/water/oil systems.

    Science.gov (United States)

    Rodríguez, Carlos; Acharya, Durga P; Hinata, Shigeki; Ishitobi, Masahiko; Kunieda, Hironobu

    2003-06-15

    The phase behavior and structure of sucrose ester/water/oil systems in the presence of long-chain cosurfactant (monolaurin) and small amounts of ionic surfactants was investigated by phase study and small angle X-ray scattering. In a water/sucrose ester/monolaurin/decane system at 27 degrees C, instead of a three-phase microemulsion, lamellar liquid crystals are formed in the dilute region. Unlike other systems in the presence of alcohol as cosurfactant, the HLB composition does not change with dilution, since monolaurin adsorbs almost completely in the interface. The addition of small amounts of ionic surfactant, regardless of the counterion, increases the solubilization of water in W/O microemulsions. The solubilization on oil in O/W microemulsions is not much affected, but structuring is induced and a viscous isotropic phase is formed. At high ionic surfactant concentrations, the single-phase microemulsion disappears and liquid crystals are favored.

  7. Critical micelle concentration of surfactants in aqueous buffered and unbuffered systems

    Energy Technology Data Exchange (ETDEWEB)

    Fuguet, Elisabet [Departament de Quimica Analitica, Universitat de Barcelona, Facultat de Quimica, Marti i Franques 1-11, 08028 Barcelona (Spain); Rafols, Clara [Departament de Quimica Analitica, Universitat de Barcelona, Facultat de Quimica, Marti i Franques 1-11, 08028 Barcelona (Spain); Roses, Marti [Departament de Quimica Analitica, Universitat de Barcelona, Facultat de Quimica, Marti i Franques 1-11, 08028 Barcelona (Spain); Bosch, Elisabeth [Departament de Quimica Analitica, Universitat de Barcelona, Facultat de Quimica, Marti i Franques 1-11, 08028 Barcelona (Spain)]. E-mail: e.bosch@ub.edu

    2005-08-29

    Critical micelle concentration (CMC) of sodium dodecyl sulphate (SDS), lithium perfluorooctanesulfonate (LPFOS), hexadecyltrimethylammonium bromide (HTAB), tetradecyltrimethylammonium bromide (TTAB), and sodium cholate (SC), surfactants commonly used as pseudostationary phases in micellar electrokinetic chromatography (MEKC), have been determined by means of three different methods: MEKC, spectrophotometry, and conductometry. Determinations have been performed in water, and also in different concentrations of phosphate buffer at pH 7.0. CMC values ranging from 8.08 (water) to 1.99 (50 mM phosphate buffer) mM for SDS, from 7.16 (water) to 2,81 (30 mM phosphate buffer) mM for LPFOS, from 3.77 (water) to 1.93 (20 mM phosphate buffer) mM for TTAB, from 0.91 (water) to {approx}0.34 (20 mM phosphate buffer) for HTAB, and around 13 mM (20 mM phosphate buffer) for SC, are obtained. The effect of the electrolyte concentration on the CMC, as well as the linear relationship between the electrolyte counter-ion concentration and the CMC are discussed. This linear relationship provides an easy way for users to estimate the CMC of a MEKC system, at a given electrolyte concentration. A comparison between experimental methods, as well as a discussion about the suitability of a given method for the determination of the CMC for a given surfactant system is also provided.

  8. Osmolality of nonionic contrast media.

    Science.gov (United States)

    Miklautz, H; Fichte, K; Wegscheider, K

    1989-01-01

    Solutions of different low osmolar contrast media (CM) obviously show clinically relevant differences in the osmolality despite equal iodine concentrations and similar molecular structure. To obtain precise and comparable data, the osmolality of five batches (usually) each of contrast media, iopamidol, iohexol, iopromide, and ioxaglate-all preparations commercially available-were measured by means of the vapor pressure method. The osmolality of the solutions of sodium meglumine ioxaglate with the same iodine concentration is lower than that of the nonionic CM examined. Iopromide showed the lowest osmolality and iohexol the highest value of the nonionic preparations. The differences are statistically significant as a rule. They are attributed to a varying association and hydration of the CM molecules in the solution.

  9. Research on the Influence of the Type of Surfactant and Concentrator in Aqueous Dispersion of Pigments.

    Science.gov (United States)

    Makarewicz, Edwin; Michalik, Agnieszka

    2014-01-01

    This work reports tests performed to evaluate the stability of aqueous dispersions of inorganic oxide pigments with different specific surface areas, with the use of anionic and non-ionic surfactants and concentrators. Color mixtures of oxide compounds of blue, green, olive and brown with the unit cell spinel structure were used as pigments. The sodium salt of sulfosuccinic acid monoester, oxyethylenated nonylphenol and ethoxylated derivatives of lauryl alcohol, fatty alcohol and fatty amine were used as surfactants. The concentrators used were: poly(vinyl alcohol), the sodium salt of carboxymethyl cellulose as well as a water-based polyurethane oligomer. The highest dispersion efficiency was found for dispersed systems in which surfactant and concentrator were incorporated in the formula. The one containing the sodium salt of carboxymethyl cellulose or polyurethane oligomer with ethoxylated saturated fatty alcohol or fatty amine was found to be the most efficient. It was discovered that a higher dispersion efficiency corresponds to pigments with larger specific surface. The efficiency is also found to improve when the concentrator is an acrylic polymer or copolymer made up of two acrylic species. In this case, the concentrator interaction with the surfactant is more effective if the value of its boundary viscosity number is higher. This observation confirms the existence of interactions between macro-chains of the concentrator and surfactant molecules forming micelles with the pigment particles.

  10. Calculation of the molecular exchanging energy of binary surfactants system on the surface monolayer of aqueous solution

    Institute of Scientific and Technical Information of China (English)

    WANG ZhengWu; YI XiZhang

    2007-01-01

    By using the binary anionic/cationic surfactants system CH3(CH2)nOSO-3/CH3(CH2)nN+(CH3)3 as an example, the molecular exchanging energy (ε) of adsorption on the surface monolayer of aqueous solution has been studied. εcan be obtained with two methods. One is from the relationship between εand the molecule interaction parameter (β). This relationship is founded by considering that the adsorption of mixed surfactants on the surface monolayer of solution satisfies the dimensional crystal model condition under which β can be obtained by testing the surface tension of solution. The other is directly from the molecular structure of surfactants with the Lennard-Jones formula. The results for the studied system show that these two methods coincide well.

  11. Changes in EEG, systemic circulation and blood gas parameters following two or six aliquots of porcine surfactant.

    Science.gov (United States)

    Lundstrøm, K E; Greisen, G

    1996-06-01

    Surfactant instillation often causes transient EEG suppression, the cause remaining unknown. To compare the timing of the EEG changes with the timing of the changes in blood gases and systemic circulation we compared two administration modes: 20 preterm infants were randomly assigned to receive the initial dose of surfactant divided into two or six aliquots. Heart rate, blood pressure and transcutaneous blood gases were measured continuously, while left ventricular output was estimated intermittently. No difference in blood gas response was found between the groups, whereas the circulatory changes occurred more gradually with six aliquots. EEG suppression was similar in the two groups and not related to the circulatory or the respiratory changes. Left ventricular output increased in all patients following surfactant instillation. We conclude that the EEG suppression is not directly related to alterations in blood gases or systemic circulation.

  12. Calculation of the molecular exchanging energy of binary surfactants system on the surface monolayer of aqueous solution

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    By using the binary anionic/cationic surfactants system CH3(CH2)nOSO3/CH3(CH2)nN+(CH3)3 as an ex-ample, the molecular exchanging energy (ε) of adsorption on the surface monolayer of aqueous solu-tion has been studied. ε can be obtained with two methods. One is from the relationship between ε and the molecule interaction parameter (β). This relationship is founded by considering that the adsorption of mixed surfactants on the surface monolayer of solution satisfies the dimensional crystal model condition under which β can be obtained by testing the surface tension of solution. The other is directly from the molecular structure of surfactants with the Lennard-Jones formula. The results for the studied system show that these two methods coincide well.

  13. New perspectives on lipid and surfactant based drug delivery systems for oral delivery of poorly soluble drugs

    DEFF Research Database (Denmark)

    Müllertz, Anette; Ogbonna, Anayo; Ren, Shan

    2010-01-01

    The aim of this review is to highlight relevant considerations when implementing a rational strategy for the development of lipid and surfactant based drug delivery system and to discuss shortcomings and challenges to the current classification of these delivery systems. We also aim to offer...

  14. Interfacial properties of nonionic micellar agregates as a function of temperatures and concentrations

    CERN Document Server

    Falconi, L; Briganti, G; D'Arrigo, G; Falconi, Luca; Maccarini, Marco; Briganti, Giuseppe; Arrigo, Giovanni D'

    1998-01-01

    By means of density, dielectric spectroscopy and sound velocity measurements we perform a systematic study on the polyoxyethylene $C_{12}E_{6}$ nonionic surfactant solutions as a function of temperature and concentration. Both density and sound velocity data, at about $34^{\\circ}C$, coincide with the value obtained for pure water. Above this temperature the density is lower than the water density whereas below it is greater, the opposite happens for the compressibility. Combining results from these different techniques we tempt a very detailed description of the evolution of the micellar interfacial properties with temperature. It is well known that nonionic surfactant solutions dehydrate, growing temperature. Our results indicate that this process is associated with a continuous change in the polymer conformation and in the local density of the micellar interface.

  15. Selection of surfactant in remediation of DDT-contaminated soil by comparison of surfactant effectiveness.

    Science.gov (United States)

    Guo, Ping; Chen, Weiwei; Li, Yueming; Chen, Tao; Li, Linhui; Wang, Guanzhu

    2014-01-01

    With an aim to select the most appropriate surfactant for remediation of DDT-contaminated soil, the performance of nonionic surfactants Tween80, TX-100, and Brij35 and one anionic surfactant sodium dodecyl benzene sulfonate (SDBS) in enhancement of DDT water solubility and desorption of DDT from contaminated soil and their adsorption onto soil and ecotoxicities were investigated in this study. Tween80 had the highest solubilizing and soil-washing ability for DDT among the four experimental surfactants. The adsorption loss of surfactants onto soil followed the order of TX-100 > Tween80 > Brij35 > SDBS. The ecotoxicity of Tween80 to ryegrass (Lolium perenne L.) was lowest. The overall performance considering about the above four aspects suggested that Tween80 should be selected for the remediation of DDT-contaminated soil, because Tween80 had the greatest solubilizing and soil-washing ability for DDT, less adsorption loss onto soil, and the lowest ecotoxicity in this experiment.

  16. Perstraction of Intracellular Pigments through Submerged Fermentation of Talaromyces spp. in a Surfactant Rich Media: A Novel Approach for Enhanced Pigment Recovery

    Directory of Open Access Journals (Sweden)

    Lourdes Morales-Oyervides

    2017-06-01

    Full Text Available A high percentage of the pigments produced by Talaromyces spp. remains inside the cell, which could lead to a high product concentration inhibition. To overcome this issue an extractive fermentation process, perstraction, was suggested, which involves the extraction of the intracellular products out of the cell by using a two-phase system during the fermentation. The present work studied the effect of various surfactants on secretion of intracellular pigments produced by Talaromyces spp. in submerged fermentation. Surfactants used were: non-ionic surfactants (Tween 80, Span 20 and Triton X-100 and a polyethylene glycerol polymer 8000, at different concentrations (5, 20, 35 g/L. The highest extracellular pigment yield (16 OD500nm was reached using Triton X-100 (35 g/L, which was 44% higher than the control (no surfactant added. The effect of addition time of the selected surfactant was further studied. The highest extracellular pigment concentration (22 OD500nm was achieved when the surfactant was added at 120 h of fermentation. Kinetics of extracellular and intracellular pigments were examined. Total pigment at the end of the fermentation using Triton X-100 was 27.7% higher than the control, confirming that the use of surfactants partially alleviated the product inhibition during the pigment production culture.

  17. Interfacial properties of nonionic micellar agregates as a function of temperatures and concentrations

    OpenAIRE

    Falconi, Luca; Maccarini, Marco; Briganti, Giuseppe; D'Arrigo, Giovanni

    1998-01-01

    By means of density, dielectric spectroscopy and sound velocity measurements we perform a systematic study on the polyoxyethylene $C_{12}E_{6}$ nonionic surfactant solutions as a function of temperature and concentration. Both density and sound velocity data, at about $34^{\\circ}C$, coincide with the value obtained for pure water. Above this temperature the density is lower than the water density whereas below it is greater, the opposite happens for the compressibility. Combining results from...

  18. Formation mechanism of CdS nanoparticles with tunable luminescence via a non-ionic microemulsion route

    Energy Technology Data Exchange (ETDEWEB)

    Angelescu, Daniel G., E-mail: dangelescu@hotmail.com; Munteanu, Gabriel [Quantum Chemistry and Molecular Structure Laboratory, Romanian Academy, ' Ilie Murgulescu' Institute of Physical Chemistry (Romania); Anghel, Dan F.; Peretz, Sandu [Romanian Academy, ' Ilie Murgulescu' Institute of Physical Chemistry, Colloidal Laboratory (Romania); Maraloiu, Adrian V.; Teodorescu, Valentin S. [National Institute of Materials Physics, Institute of Atomic Physics (Romania)

    2013-01-15

    We investigated the synthesis of CdS nanoparticles via an optimized water-in-oil microemulsion route that used the non-ionic surfactant-based system H{sub 2}O-n-octane-Brij30/1-octanol. For that purpose, a microemulsion that contained Cd(II) ions ({mu}e1) and another microemulsion that contained S{sup 2-} ions ({mu}e2) were combined. To investigate the ways in which the non-ionic microemulsion characteristics controlled the size and emission properties of colloidal CdS quantum dots, {mu}e1 and {mu}e2 with tunable and robust similar structure were prepared. This requirement was fulfilled by matching the water emulsification failure boundary (wefb) of the two microemulsions and carrying out synthesis along this boundary. Dynamic light scattering and fluorescence probe techniques were used to investigate the size and interfacial organization of the microemulsion water droplets, and the CdS nanoparticles were characterized by UV-Vis and static fluorescence spectrometry, TEM and HRTEM. Nanoparticles of diameter 4.5-5.5 nm exhibiting enhanced band edge emission were produced by increasing the water content of the precursor microemulsions. The experimental results were combined with a Monte Carlo simulation approach to demonstrate that growth via coagulation of seed nuclei represented the driving mechanism for the CdS nanoparticle formation in the water-in-oil microemulsion.

  19. Surface-enhanced Raman spectroscopy of surfactants on silver electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Soncheng; Birke, R.L.; Lombardi, J.R. (City Univ. of New York, NY (USA))

    1990-03-08

    Surface-enhanced Raman spectroscopy (SERS) has been used to study different kinds of surfactants (cationic, anionic, and nonionic surfactants) adsorbed on a roughened Ag electrode. Spectral assignments are made for the SERS spectrum of cetylpyridinium chloride (CPC), and it is shown that the molecule is oriented with its pyridinium ring end-on at the electrode surface at potentials positive to the point of zero charge (pzc) on Ag.

  20. Green Cosmetic Surfactant from Rice: Characterization and Application

    OpenAIRE

    Ibrahim Hanno; Marisanna Centini; Cecilia Anselmi; Claudia Bibiani

    2015-01-01

    During recent years, microwave irradiation has been extensively used for performing green organic synthesis. The aim of this study was to synthesize, through a microwave-assisted irradiation process, a natural surfactant with O/W emulsifying properties. Our attention was focused on polyglycerol esters of fatty acids that are biocompatible and biodegradable non-ionic surfactants widely used in food and cosmetic products. The emulsifier was obtained using vegetable raw material from renewable s...

  1. A Novel Surfactant-free Microemulsion System: N,N-Dimethyl Formamide/Furaldehyde/H2O

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Generally, a microemulsion consists of oil, water, surfactant and sometimes cosurfactant. Herein, for the first time to our knowledge, a novel surfactant-free microemulsion (SFME), consisting of furaldehyde (oil phase), water and N,N-dimethyl formamide (DMF) without the amphiphilic molecular structure of traditional surfactant is re-ported. The phase behavior of the ternary system was investigated, finding that a single-phase microemulsion region and a two-phase region were formed. The electrical conductivity measurement was employed to investigate the sin-gle-phase microemulsion region. On the basis of the percolation theory, the single-phase microemulsion region was identified to consist of three different microregions: furaldehyde-in-water (O/W), bicontinuous region and water-in-furaldehyde (W/O), which were further proved by freeze-fracture transmission electron microscopy (FF-TEM) observations. The diameter of the microemulsion spherical droplets is in the range of 40-70 nm.

  2. The effect of selected surfactants on the structure of a bicellar system (DMPC/DHPC) studied by SAXS

    Science.gov (United States)

    Kozak, Maciej; Domka, Ludwik; Jurga, Stefan

    2007-11-01

    The stabilizing or disturbing effect of different surfactants on the bicellar phase of phospholipids significantly depends on their type. The effect of different surfactants on the bicellar structure made of a mixture of phospholipids 1,2-dimyristoyl-sn-glycero-3-phosphocholine and 1,2-dihexanoyl-sn-glycero-3-phospho-choline (DMPC/DHPC) has been studied by the small angle scattering of synchrotron radiation. The study has been performed for three surfactants: dodecyldimethyl-(hexyloxymethyl)ammonium chloride, n-undecylammonium chloride and t-octylphenoxypolyethoxyethanol (Triton X-100) introduced into a bicellar solution of DMPC/DHPC (2.8:1). The bicellar phase has been disturbed in the shortest time in the presence of dodecyldimethyl-(hexyloxymethyl)ammonium chloride in this system a transition from the bicellar to lamellar structure has been directly visible. The changes have been less pronounced in the presence of undecylammonium chloride and practically not noted in the presence of Triton X-100.

  3. A study of the distribution of polymer/surfactant coacervate between solution and foam in archetypal shampoo systems.

    Science.gov (United States)

    Wilgus, Leigh Ann; Davis, Kathleen; Labeaud, Lauren; Gandolfi, Lisa; Lochhead, Robert Y

    2011-01-01

    The research reported here attempted to answer the question, "is the foam important in delivering coacervates from shampoos." In order to answer this question, we have measured the amount of polymer in the foam and in the liquid phases of several cationic polymer/anionic surfactant systems by gravimetry and by FTIR techniques. In all cases studied, we discovered that the concentration of solids and, especially the polymer, in the liquid phase and in the foam phase were essentially the same. We conclude that the foam is unlikely to be an important factor in the topical delivery of polymer/surfactant coacervates.

  4. Fusion of Nonionic Vesicles

    DEFF Research Database (Denmark)

    Bulut, Sanja; Oskolkova, M. Z.; Schweins, R.

    2010-01-01

    We present an experimental study of vesicle fusion using light and neutron scattering to monitor fusion events. Vesicles are reproducibly formed with an extrusion procedure using an single amphiphile triethylene glycol mono-n-decyl ether in water. They show long-term stability for temperatures...... around 20 C, but at temperatures above 26 C we observe an increase in the scattered intensity due to fusion. The system is unusually well suited for the study of basic mechanisms of vesicle fusion. The vesicles are flexible with a bending rigidity of only a few k(H)T. The monolayer spontaneous curvature...

  5. Novel Highly Flexible Wormlike Micelles Formed by Cetylpyridinium Chloride and Trioxyethylene Monododecyl Ether Surfactants

    Directory of Open Access Journals (Sweden)

    Firoz Kapadia

    2014-06-01

    Full Text Available The impact of small nonionic hydrophobic molecule, trioxyethylene monododecyl ether (C12EO3, on the viscoelastic properties of aqueous solutions of cetylpyridinium chloride (CPC is studied. As the C12EO3 concentration increases, the viscosity passes through a maximum. Dynamic rheological measurements revealed a comprehensive picture of how C12EO3 affects the different length scales in the entangled wormlike micelles. Increase in the viscosity can normally be caused by insertion of amphiphilic C12EO3 molecules into the cationic surfactant (CPC layer, or micellar swelling, caused by solubilization of very hydrophobic molecules in the micellar core. The partial phase behavior and rheology of this mixed surfactant systems is studied.

  6. EFFECT OF SURFACTANTS ON Ni-TiN NANOCOMPOSITE COATINGS PREPARED BY ULTRASONIC ELECTRODEPOSITION

    Institute of Scientific and Technical Information of China (English)

    XIA Fafeng; JIA Zhenyuan; WU Menghua; LI Zhi

    2008-01-01

    Ni-TiN nanocomposite coatings were prepared by ultrasonic electrodeposition, and the effects of the surfactants on the coatings were investigated and the microstructure and micro rigidity of the coatings were characterized. Samples were also submitted to corrosion tests in 3% NaCl solution. The results showed that the surfactants had great effects on Ni-TiN nanocomposite coatings. The composite coatings prepared by ultrasonic electrodeposition with the surfactants were better than that of the coatings prepared without surfactants. The favorable properties of Ni-TiN nanocomposite coatings were prepared with the mixing of the non-ion and positive ion surfactants. The concentration of the mixing was 80 mg/L, and the ratio of the non-ion and positive ion surfactants was 1: 2.

  7. Self-assembled systems of water soluble metal 8-hydroxyquinolates with surfactants and conjugated polyelectrolytes

    DEFF Research Database (Denmark)

    Burrows, Hugh D.; Costa, Telma; Luisa Ramos, M.

    2016-01-01

    We have studied the interaction of 8-hydroxyquinoline-5-sulfonate (8-HQS) with the metal ions Al(III) and Zn(II) in aqueous solution in the presence of tetraalkylammonium surfactants using UV/vis absorption, fluorescence, NMR spectroscopy and electrical conductivity measurements, complemented by ...... assembly between the conjugated polyelectrolyte and the metal/8-HQS complex, as demonstrated by electronic energy transfer. The potential of these systems in sensing, light harvesting, and electron injection/transport layers in organic semiconductor devices is discussed....... by DFT calculations and molecular dynamics (MD) simulations. Under appropriate conditions, complexes between 8-HQS and metal ions form rapidly, and have similar electronic, spectroscopic and photophysical properties to the corresponding metal quinolates, such as Alq3. These interact with the cationic...

  8. Capillary electrophoresis investigation on equilibrium between polymer-related and surfactant-related species in aqueous polymer-surfactant solutions.

    Science.gov (United States)

    Wu, Yefan; Chen, Miaomiao; Fang, Yun; Zhu, Meng

    2017-03-17

    It was inferred from aqueous solution behavior of nonionic polymers and anionic surfactants that the formation of charged polymer-bound surfactant micelle above critical aggregation concentration (cac) and the formation of free surfactant micelle beyond polymer saturation point (psp), but there was still a lack of direct experimental evidence for the considered equilibrium chemical species. Three modes of capillary electrophoresis are applied in this paper to study the complexation between nonionic polymers, polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG), and sodium dodecylbenzenesulfonate (SDBS) by successfully distinguishing the imaginary charged polymer-bound SDBS micelle from nonionic polymer and SDBS molecule. Perhaps even more important, it is the action of SDBS as both a main surfactant and a UV probe that makes the free surfactant micelle emerged in electropherogram beyond psp, and thus makes it possible for the first time to provide the equilibrium relationship of the polymer-related and the surfactant-related species in the concentration regions divided into by cac and psp. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Interactions of Proline in Non-aqueous Anionic, Cationic and Nonionic Surfactants at Different Temperatures%不同温度下脯氨酸在非水阴离子、阳离子及非离子型表面活性剂中的作用

    Institute of Scientific and Technical Information of China (English)

    ALI Anwar; SHAHJAHAN

    2008-01-01

    Density and viscosity data of proline (Pro) in sodium dodecyl sulfate/cetyltrimethylammonium bromide/poly (oxyethylene) isooctyl phenyl ether in formamide were measured at 298.15, 303.15, 308.15, and 313.15K and 0.1MPa. The density data were utilized to evaluate standard partial molar volumes (φ0V) and partial molar isobaric expansibility (φ0E). The viscosity data were used to evaluate A-and B-coefficients, free energy of activation of viscous flow (⊿μ0*1) and (⊿μ0*2), per mole of solvent and solute respectively, enthalpy (⊿H*) and entropy (⊿S*) of activation of viscous flow. The results obtained were utilized in the qualitative elucidation of the Pro-surfactant/formamide and Pro-Pro interactions in the present systems.

  10. Identification of co-existing cationic surfactants with preliminary separation on silica HPTLC plates using mixed aqueous sodium chloride-ethanol as eluent

    Directory of Open Access Journals (Sweden)

    Ali Mohammad

    2015-12-01

    Full Text Available A new high-performance thin-layer chromatographic system comprising of silica gel 60 HPTLC plates as stationary phase and ethanol-5% aqueous sodium chloride (8:2 as mobile phase has been identified as most suitable for separation of quaternary mixture of cationic surfactants. Separation efficacy of developed method has been established by obtaining well-resolved densitogram of separated spots. To check the versatility, effects of presence of metal cations, inorganic anions, amino acids, vitamins and non-ionic surfactants as impurities were also examined. The chromatographic parameters like ΔRF, separation factor (α, resolution (RS and limit of detection were also calculated. The proposed method is applicable for the identification of surfactants in eye drops and Colgate Plax mouthwash.

  11. Dependence of the solubility of atmospheric oxygen in weakly alkaline aqueous solutions on surfactant concentration

    Science.gov (United States)

    Chistyakova, G. V.; Koksharov, S. A.; Vladimirova, T. V.

    2012-11-01

    The solubility of atmospheric oxygen in solutions of surfactants of different natures at 293 K and pH 8 is determined by gas chromatography. It is found that additives of nonionic surfactants decrease the oxygen content in the solution in the premicellar region and increase its solubility in the micellar region. It is shown that, for anionic surfactants, a decrease in the solubility of O2 is observed over the entire concentration range.

  12. Effect of low concentrations of synthetic surfactants on polycyclic aromatic hydrocarbons (PAH) biodegradation

    OpenAIRE

    A. C. Rodrigues; Nogueira, R; Melo, L. F.; A. G. Brito

    2013-01-01

    The present study is focused on the effect of synthetic surfactants, at low concentration, on the kinetics of polycyclic aromatic hydrocarbons (PAH) biodegradation by Pseudomonas putida ATCC 17514 and addresses the specific issue of the effect of the surfactant on bacterial adhesion to PAH, which is believed to be an important mechanism for the uptake of hydrophobic compounds. For that purpose, three surfactants were tested, namely, the nonionic Tween 20, the anionic sodium dodecyl sulphate (...

  13. Modification of the activity of an a-amylase from Bacillus licheniformis by several surfactants

    OpenAIRE

    2006-01-01

    The influence of different commercial surfactants on the enzymatic activity of a commercial ??-amylase from Bacillus licheniformis (Termamyl 300 L) has been studied. As non-ionic surfactants, alkyl polyglycosides (Glucopon?? 215, Glucopon?? 600 and Glucopon?? 650) were studied, as were fatty alcohol ethoxylates (Findet 1214N/23 and Findet 10/15), and nonyl phenol ethoxylate (Findet 9Q/21.5NF). Also, an anionic surfactant, linear alkyl benzene sulfonate (LAS) was assayed. In general, none of t...

  14. Influence of metacide - surfactant complexes on agricultural crops

    Directory of Open Access Journals (Sweden)

    Orynkul Esimova

    2014-12-01

    Full Text Available The complexes based on surfactants and polyhexamethyleneguanidine hydrochloride (metacide are important for agriculture. This paper considers compositions of known bactericidal metacide with different surfactants: anionic surfactant sodium dodecylsulphate (DDSNa and nonionic surfactant Tween 80 (monooleate of oxyethylenated anhydrosorbitols. The effect of individual components and associates of metacide and surfactants on productivity and infection of cereals was studied. According to the study, the highest productivity and infection rate were shown by the associate of metacide and Tween-80. At concentration of Tween-80 in aqueous solution equal to 0.001% in combination with metacide, efficiency was 98% at 0% infection. The surface tension and the wetting of metacide, DDSNa, Tween-80, and associates of metacide with surfactants were studied. In comparison with individual components, metacide-DDSNa and metacide-Tween-80 associates have higher surface activity.

  15. Surfactants in the environment.

    Science.gov (United States)

    Ivanković, Tomislav; Hrenović, Jasna

    2010-03-01

    Surfactants are a diverse group of chemicals that are best known for their wide use in detergents and other cleaning products. After use, residual surfactants are discharged into sewage systems or directly into surface waters, and most of them end up dispersed in different environmental compartments such as soil, water or sediment. The toxic effects of surfactants on various aquatic organisms are well known. In general, surfactants are present in the environment at levels below toxicity and in Croatia below the national limit. Most surfactants are readily biodegradable and their amount is greatly reduced with secondary treatment in wastewater treatment plants. The highest concern is the release of untreated wastewater or wastewater that has undergone primary treatment alone. The discharge of wastewater polluted with massive quantities of surfactants could have serious effects on the ecosystem. Future studies of surfactant toxicities and biodegradation are necessary to withdraw highly toxic and non-biodegradable compounds from commercial use and replace them with more environmentally friendly ones.

  16. Study of drug supersaturation for rational early formulation screening of surfactant/co-solvent drug delivery systems.

    Science.gov (United States)

    Stillhart, Cordula; Cavegn, Martin; Kuentz, Martin

    2013-02-01

    To advance in vitro screening of surfactant/co-solvent formulations in early development by considering drug supersaturation and the mechanism of solubilization upon aqueous dilution. Two surfactant/co-solvent model systems were studied at practically relevant aqueous dilution ratios. Precipitation of the model drug fenofibrate was characterized by focused beam reflectance measurement, X-ray diffraction, and Raman spectroscopy. We calculated drug supersaturation in diluted systems and introduced a theoretical model to study the role of excipient interaction in the process of drug solubilization. Finally, vehicle phase changes upon dilution were examined using dynamic light scattering and ultrasound analysis. Phase changes occurred at low dilution levels, while more extensive dilution barely led to further structural changes. In undiluted formulations, ethanol-surfactant domains were responsible for fenofibrate solubilization. In dispersed formulations, however, the co-solvent partitioned out of the surfactant microstructure, leading to drug solubilization by independent micellization and co-solvency. This loss of excipient interaction caused formulation-specific supersaturation, which was indicative for the risk of drug precipitation. Experimental protocols of in vitro formulation screening should include both low and high dilution levels of physiological relevance. The study of excipient interaction and estimation of supersaturation allows the identification of formulations that are prone to drug precipitation. © 2012 The Authors. JPP © 2012. Royal Pharmaceutical Society.

  17. Inhibition of lipase-catalyzed hydrolysis of emulsified triglyceride oils by low-molecular weight surfactants under simulated gastrointestinal conditions.

    Science.gov (United States)

    Li, Yan; McClements, David Julian

    2011-10-01

    The effect of low-molecular weight surfactants on the digestibility of lipids in protein-stabilized corn oil-in-water emulsions was studied using an in vitro digestion model. The impact of non-ionic (Tween 20, Tween 80, Brij35), anionic (SDS), and cationic (DTAB) surfactants on the rate and extent of lipid digestion was studied. All surfactants were found to inhibit lipid digestion at sufficiently high concentrations, with half-maximal inhibitory concentrations (IC50) of 1.2% for Tween 20, 0.7% for Tween 80, 2.8% for Brij35, 1.1% for SDS, and 1.4% for DTAB. The effectiveness of the surfactants at inhibiting lipid digestion was therefore not strongly correlated to the electrical characteristics of the surfactant head group, since the IC50 increased in the following order: Tween 80>SDS>Tween 20>DTAB>Brij35. The ability of these low-molecular weight surfactants to inhibit lipid digestion was attributed to a number of potential mechanisms: (i) prevention of lipase/co-lipase adsorption to the oil-water interface; (ii) formation of interfacial complexes; (iii) direct interaction and inactivation of lipase/co-lipase. Interestingly, DTAB increased the rate and extent of lipid digestion when present at relatively low concentrations. This may have been because this cationic surfactant facilitated the adsorption of lipase to the droplet surfaces through electrostatic attraction, or it bound directly to the lipase molecule thereby changing its structure and activity. A number of the surfactants themselves were found to be susceptible to enzyme digestion by pancreatic enzymes in the absence of lipids: Tween 20, Tween 80, Brij35, and DTAB. This work has important implications for the development of emulsion-based delivery systems for food and pharmaceutical applications.

  18. pH-switchable structural evolution in aqueous surfactant-aromatic dibasic acid system.

    Science.gov (United States)

    Rose J, Linet; Tata, B V R; Aswal, V K; Hassan, P A; Talmon, Yeshayahu; Sreejith, Lisa

    2015-01-01

    Structural transitions triggered by pH in an aqueous micellar system comprising of a cationic surfactant (cetylpyridinium chloride) and an aromatic dibasic acid (phthalic acid) was investigated. Reversible switching between liquid-like and gel-like states was exhibited by the system on adjusting the solution pH. Self-assembled structures, responsible for the changes in flow properties were identified using rheology, light scattering techniques and cryogenic Transmission Electron Microscopy (cryo-TEM). High-viscosity, shear-thinning behavior and Maxwell-type dynamic rheology shown by the system at certain pH values suggested the growth of spheroidal/short cylindrical micelles into long and entangled structures. Light scattering profiles also supported the notion of pH-induced microstructural transitions in the solution. Cryo-TEM images confirmed the presence of spheroidal/short cylindrical micelles in the low-viscosity sample whereas very long and entangled thread-like micelles in the peak viscosity sample. pH-dependent changes in the micellar binding ability of phthalic acid is proposed as the key factor regulating the morphological transformations and related flow properties of the system.

  19. Tuning of protein-surfactant interaction to modify the resultant structure.

    Science.gov (United States)

    Mehan, Sumit; Aswal, Vinod K; Kohlbrecher, Joachim

    2015-09-01

    Small-angle neutron scattering and dynamic light scattering studies have been carried out to examine the interaction of bovine serum albumin (BSA) protein with different surfactants under varying solution conditions. We show that the interaction of anionic BSA protein (pH7) with surfactant and the resultant structure are strongly modified by the charge head group of the surfactant, ionic strength of the solution, and mixed surfactants. The protein-surfactant interaction is maximum when two components are oppositely charged, followed by components being similarly charged through the site-specific binding, and no interaction in the case of a nonionic surfactant. This interaction of protein with ionic surfactants is characterized by the fractal structure representing a bead-necklace structure of micellelike clusters adsorbed along the unfolded protein chain. The interaction is enhanced with ionic strength only in the case of site-specific binding of an anionic surfactant with an anionic protein, whereas it is almost unchanged for other complexes of cationic and nonionic surfactants with anionic proteins. Interestingly, the interaction of BSA protein with ionic surfactants is significantly suppressed in the presence of nonionic surfactant. These results with mixed surfactants thus can be used to fold back the unfolded protein as well as to prevent surfactant-induced protein unfolding. For different solution conditions, the results are interpreted in terms of a change in fractal dimension, the overall size of the protein-surfactant complex, and the number of micelles attached to the protein. The interplay of electrostatic and hydrophobic interactions is found to govern the resultant structure of complexes.

  20. Medidas de tensão superficial pelo método de contagem de gotas: descrição do método e experimentos com tensoativos não-iônicos etoxilados Surface tension measurement by drop counting method: method description and experiments with etoxilated non-ionic surfactants

    Directory of Open Access Journals (Sweden)

    Érico Teixeira Neto

    2009-01-01

    Full Text Available Surface tension knowledge of surfactants aqueous solutions is important during amphiphilic molecule manufacturing and new product development, as feedback information to handle synthesis parameters to target performance. Drop counting method is an interesting simplification of drop weight method for surface tension measurements. A simple laboratory measurement device, with capability for temperature control, was assembled to allow investigation of ethoxylated surfactants. The implementation of the method was preceded by a detailed investigation of two factors that may affect the measured surface tension: drop formation velocity and surfactant ethoxylation degree. The limitations of the method are discussed on this basis.

  1. The selective partitioning of the oligomers of polyethoxylated surfactant mixtures between interface and oil and water bulk phases.

    Science.gov (United States)

    Graciaa, Alain; Andérez, José; Bracho, Carlos; Lachaise, Jean; Salager, Jean-Louis; Tolosa, Laura; Ysambertt, Fredy

    2006-11-16

    Because their affinities for the oil and water phases vary considerably with the number of ethylene oxide units in their hydrophilic group, the ethoxylated nonionic species occurring in commercial products tend to behave in a non-collective way, with the low ethoxylation oligomers partitioning mostly in the oil phase. This results in a surfactant mixture at the interface which is more hydrophilic than the one which was introduced in the system in the first place. The pseudophase model is used to study the partitioning in Winsor III type systems, and to estimate the deviation of the interfacial mixture composition from the overall one. New results indicate that the selective partitioning into the oil phase increases when the oil phase becomes aromatic, when the total surfactant concentration decreases and when the water-to-oil ratio decreases.

  2. The effects of pH and surfactants on the absorption and fluorescence properties of ochratoxin A and zearalenone.

    Science.gov (United States)

    Li, Taihua; Kim, Bo Bae; Ha, Tae Hwan; Shin, Yong-Beom; Kim, Min-Gon

    2015-11-01

    The pH and surfactant dependencies of the absorption and fluorescence properties of ochratoxin A (OTA) and zearalenone (ZEN), the main mycotoxins found as contaminants in foods and feeds, were evaluated. Three surfactants with different ionic properties were investigated, namely sodium dodecyl sulfate (SDS, anionic), Tween 20 (nonionic) and hexadecyltrimethylammonium bromide (CTAB, cationic). The results show that the effects of pH on the absorption wavelength maxima and fluorescence efficiencies of the mycotoxins, which are a consequence of the presence of acidic phenol and/or carboxyl containing fluorophores, are dependent on the ionic nature of the added surfactants. Specifically, the fluorescence responses to pH changes of OTA and ZEN are similar in the presence or absence of Tween 20 and SDS. By contrast, the pH-dependent fluorescence properties of these mycotoxins are altered when CTAB is present in the solutions. Moreover, unlike OTA, ZEN in aqueous solution displays almost no fluorescence. However, fluorescence enhancement takes place when surfactants are present in aqueous solutions of this mycotoxin. The results of this study demonstrate that the different microenvironments, present in the organized micellar systems created by the individual surfactants, can be potentially employed to modulate the sensitivities and selectivities of the fluorescence detection of OTA or ZEN. Copyright © 2015 John Wiley & Sons, Ltd.

  3. Synthesis of nonionic-anionic colloidal systems based on alkaline and ammonium β-nonylphenol polyethyleneoxy (n = 3-20) propionates/dodecylbenzenesulfonates with prospects for food hygiene

    Science.gov (United States)

    2012-01-01

    Background The main objective of this work was to obtain a binary system of surface-active components (nonionic soap – alkaline and/or ammonium dodecylbenzenesulfonate) with potential competences in food hygiene, by accessing a scheme of classical reactions (cyanoethylation, total acid hydrolysis and stoichiometric neutralization with inorganic alkaline and/or organic ammonium bases) adapted to heterogeneously polyethoxylated nonylphenols (n = 3-20). In the processing system mentioned, dodecylbenzenesulfonic acid, initially the acid catalyst for the exhaustive hydrolysis of β-nonylphenolpolyethyleneoxy (n = 3-20) propionitriles, becomes together with the nonionic soap formed the second surface-active component of the binary system. Results In the reaction scheme adopted the influence of the main operating (duration, temperature, molar ratio of reagents) and structural parameters (degree of oligomerization of the polyoxyethylene chain) on the processing yields for the synthetic steps was followed. The favorable role of the polyoxyethylene chain size is remarked, through its specific conformation and its alkaline cations sequestration competences on the yields of cyanoethylation, but also the beneficial influence of phase-transfer catalysts in the total acid hydrolysis step. The chemical stability of dodecylbenzenesulfonic acid (DBSH) at the temperature and strongly acidic pH of the reaction environment is confirmed. The controlled change of the amount of DBSH in the final binary system will later confer it potential colloidal competences in food hygiene receipts. Conclusions The preliminary synthetic tests performed confirmed the prospect of obtaining a broad range of useful colloidal competences in various food hygiene scenarios. PMID:22958389

  4. Synthesis of nonionic-anionic colloidal systems based on alkaline and ammonium β-nonylphenol polyethyleneoxy (n = 3-20 propionates/dodecylbenzenesulfonates with prospects for food hygiene

    Directory of Open Access Journals (Sweden)

    Jianu Calin

    2012-09-01

    Full Text Available Abstract Background The main objective of this work was to obtain a binary system of surface-active components (nonionic soap – alkaline and/or ammonium dodecylbenzenesulfonate with potential competences in food hygiene, by accessing a scheme of classical reactions (cyanoethylation, total acid hydrolysis and stoichiometric neutralization with inorganic alkaline and/or organic ammonium bases adapted to heterogeneously polyethoxylated nonylphenols (n = 3-20. In the processing system mentioned, dodecylbenzenesulfonic acid, initially the acid catalyst for the exhaustive hydrolysis of β-nonylphenolpolyethyleneoxy (n = 3-20 propionitriles, becomes together with the nonionic soap formed the second surface-active component of the binary system. Results In the reaction scheme adopted the influence of the main operating (duration, temperature, molar ratio of reagents and structural parameters (degree of oligomerization of the polyoxyethylene chain on the processing yields for the synthetic steps was followed. The favorable role of the polyoxyethylene chain size is remarked, through its specific conformation and its alkaline cations sequestration competences on the yields of cyanoethylation, but also the beneficial influence of phase-transfer catalysts in the total acid hydrolysis step. The chemical stability of dodecylbenzenesulfonic acid (DBSH at the temperature and strongly acidic pH of the reaction environment is confirmed. The controlled change of the amount of DBSH in the final binary system will later confer it potential colloidal competences in food hygiene receipts. Conclusions The preliminary synthetic tests performed confirmed the prospect of obtaining a broad range of useful colloidal competences in various food hygiene scenarios.

  5. Emulsion of aqueous-based nonspherical droplets in aqueous solutions by single-chain surfactants: templated assembly by nonamphiphilic lyotropic liquid crystals in water.

    Science.gov (United States)

    Varghese, Nisha; Shetye, Gauri S; Bandyopadhyay, Debjyoti; Gobalasingham, Nemal; Seo, JinAm; Wang, Jo-Han; Theiler, Barbara; Luk, Yan-Yeung

    2012-07-24

    Single-chain surfactants usually emulsify and stabilize oily substances into droplets in an aqueous solution. Here, we report a coassembly system, in which single types of anionic or non-ionic surfactants emulsify a class of water-soluble nonamphiphilic organic salts with fused aromatic rings in aqueous solutions. The nonamphiphilic organic salts are in turn promoted to form droplets of water-based liquid crystals (chromonic liquid crystals) encapsulated by single-chain surfactants. The droplets, stabilized against coalescence by encapsulated in a layer (or layers) of single chain surfactants, are of both nonspherical tactoid (elongated ellipsoid with pointy ends) and spherical shapes. The tactoids have an average long axis of ∼9 μm and a short axis of ∼3.5 μm with the liquid crystal aligning parallel to the droplet surface. The spherical droplets are 5-10 μm in diameter and have the liquid crystal aligning perpendicular to the droplet surface and a point defect in the center. Cationic and zwitterionic surfactants studied in this work did not promote the organic salt to form droplets. These results illustrate the complex interplay of self-association and thermodynamic incompatibility of molecules in water, which can cause new assembly behavior, including potential formation of vesicles or other assemblies, from surfactants that usually form only micelles. These unprecedented tactoidal shaped droplets also provide potential for the fabrication of new soft organic microcapsules.

  6. Alcohol--Induced Polyelectrolyte-Surfactant Complex Coacervate Systems: Characterization and Applications in Enzyme and Protein Extraction

    Science.gov (United States)

    Nejati Moshtaghin, Mahboubeh

    The focus of this thesis is to achieve a better understanding of the newly discovered surfactant-polyelectrolyte complex coacervate (SPCC) systems induced by fluoroalcohol/acid as well as short chain aliphatic alcohol; and to elucidate their applications in extraction and enrichment of proteins and enzyme. We have discovered that fluoroalcohols and --acids induce complex coacervation and phase separation in the aqueous mixtures of oppositely charged anionic polyelectrolytes; specifically, sodium salts of polyacrylic acid and polymethacrylic acid and cationic surfactant (cetyltrimethylammonium bromide, CTAB) over a broad range of concentrations of mole fractions of the oppositely charged amphiphiles. Accordingly, these new classes of coacervators will significantly broaden the scope and facilitate engineering of new coacervate phases. Toward these goals, we have inspected the formation of surfactant-polyelectrolyte complex coacervates in the presence of fluoroalcohols namely hexafluoroisopropanol (HFIP) and Trifluoroethanol (TFE). Furthermore, the extent of coacervation as a function of concentrations the system components, and charge ratios of the oppositely charged amphiphiles has been investigated. Polyelectrolytes are considered to be milder reagents, as compared to surfactants, regarding proteins denaturation. This highlights the importance of a detailed investigation of the efficiency of our coacervate systems for extraction and preconcentration of proteins and enzymes, especially, when the biological activity of the extracted proteins needs to be maintained based on the objectives mentioned above, the results of the investigations have been organized in four chapters. In Chapter II, the phase behavior of the FA-SPCC will be investigated. The objective is to examine the phase behavior and phase properties with respect to the extent of coacervation in different solution conditions. In particular, the effects of different solution variables such as concentration

  7. Experimental study of surfactant transfer in fluid systems in microgravity conditions

    Science.gov (United States)

    Kostarev, K. G.; Levtov, V. L.; Romanov, V. V.; Shmyrov, A. V.; Viviani, A.

    2010-02-01

    The paper presents the results of the space experiment studying the process of surfactant dissolution from a binary fluid drop in microgravity conditions. The experiment was performed during the flight of the space satellite "Foton M-3" in September 2007. Investigation of the surfactant diffusion was made using a new original setup based on the interferometric method. The experimental cuvette represented a thin Hele-Shaw cell filled with water, which surrounded a drop in the form of a short liquid cylinder with a free lateral surface. The drop consisted of a binary mixture, in which one of the components was the surfactant easily dissolved in water. The use of interferometry made it possible to visualize and investigate evolution of the surfactant distributions and the flow structures in the drop and the surrounding liquid. The characteristic stages of the dissolution process were identified, and the rate of the concentration front propagation was defined. It was shown that in microgravity conditions the process of surfactant diffusion through the interface did not initiate an intensive solutal Marangoni convection as contrasted to the case of terrestrial simulation. The observed phenomenon has its origins in the long-lived fields of surfactant concentration formed near the interface due to the absence of the gravitational mechanisms of motion and large characteristic time of admixture diffusion which is hundreds of times longer than the time of thermal diffusion.

  8. Bio-inspired pulmonary surfactant-modified nanogels: A promising siRNA delivery system.

    Science.gov (United States)

    De Backer, Lynn; Braeckmans, Kevin; Stuart, Marc C A; Demeester, Jo; De Smedt, Stefaan C; Raemdonck, Koen

    2015-05-28

    Inhalation therapy with small interfering RNA (siRNA) is a promising approach in the treatment of pulmonary disorders. However, clinical translation is severely limited by the lack of suitable delivery platforms. In this study, we aim to address this limitation by designing a novel bioinspired hybrid nanoparticle with a core-shell nanoarchitecture, consisting of a siRNA-loaded dextran nanogel (siNG) core and a pulmonary surfactant (Curosurf®) outer shell. The decoration of siNGs with a surfactant shell enhances the colloidal stability and prevents siRNA release in the presence of competing polyanions, which are abundantly present in biofluids. Additionally, the impact of the surfactant shell on the biological efficacy of the siNGs is determined in lung cancer cells. The presence of the surfactants substantially reduces the cellular uptake of siNGs. Remarkably, the lowered intracellular dose does not impede the gene silencing effect, suggesting a crucial role of the pulmonary surfactant in the intracellular processing of the nanoparticles. In order to surmount the observed reduction in cellular dose, folate is incorporated as a targeting ligand in the pulmonary surfactant shell to incite receptor-mediated endocytosis. The latter substantially enhances both cellular uptake and gene silencing potential, achieving efficient knockdown at siRNA concentrations in the low nanomolar range.

  9. Surfactant effects on alpha factors in full-scale wastewater aeration systems.

    Science.gov (United States)

    Rosso, D; Larson, L E; Stenstrom, M K

    2006-01-01

    Aeration is an essential process in the majority of wastewater treatment processes, and accounts for the largest fraction of plant energy costs. Aeration systems can achieve wastewater oxygenation by shearing the surface (surface aerators) or releasing bubbles at the bottom of the tank (coarse- or fine-bubble aerators). Surfactants accumulate on gas-liquid interfaces and reduce mass transfer rates. This reduction in general is larger for fine-bubble aerators. This study was conducted to evaluate mass transfer effects on the characterization and specification of aeration systems in clean and process water conditions. Tests at different interfacial turbulence regimes were analysed, showing higher gas transfer depression for lower turbulence regimes. Higher turbulence regimes can offset contamination effects, at the expense of operating efficiency. This phenomenon is characteristic of surface aerators and coarse bubble diffusers and is here discussed. The results explain the variability of alpha factors measured at small scale, due to uncontrolled energy density. Results are also reported in dimensionless empirical correlations that describe mass transfer as a function of physiochemical and geometrical characteristics of the aeration process.

  10. A study of surfactant interaction in cement-based systems and the role of the surfactant in frost protection

    Science.gov (United States)

    Tunstall, Lori Elizabeth

    Air voids are deliberately introduced into concrete to provide resistance against frost damage. However, our ability to control air distribution in both traditional and nontraditional concrete is hindered by the limited amount of research available on air-entraining agent (AEA) interaction with both the solid and solution components of these systems. This thesis seeks to contribute to the information gap in several ways. Using tensiometry, we are able to quantify the adsorption capacity of cement, fly ash, and fly ash carbon for four commercial AEAs. These results indicate that fly ash interference with air entrainment is due to adsorption onto the glassy particles tucked inside carbon, rather than adsorption onto the carbon itself. Again using tensiometry, we show that two of the AEA show a stronger tendency to micellize and to interact with calcium ions than the others, which seems to be linked to the freezing behavior in mortars, since mortars made with these AEA require smaller dosages to achieve similar levels of protection. We evaluate the frost resistance of cement and cement/fly ash mortars by measuring the strain in the body as it is cooled and reheated. All of the mortars show some expansion at temperatures ≥ -42 °C. Many of the cement mortars are able to maintain net compression during this expansion, but none of the fly ash mortars maintain net compression once expansion begins. Frost resistance improves with an increase in AEA dosage, but no correlation is seen between frost resistance and the air void system. Thus, another factor must contribute to frost resistance, which we propose is the microstructure of the shell around the air void. The strain behavior is attributed to ice growth surrounding the void, which can plug the pores in the shell and reduce or eliminate the negative pore pressure induced by the ice inside the air void; the expansion would then result from the unopposed crystallization pressure, but this must be verified by future work

  11. Unique Phase Behaviors in the Gemini Surfactant/EAN Binary System: The Role of the Hydroxyl Group.

    Science.gov (United States)

    Li, Qintang; Wang, Xudong; Yue, Xiu; Chen, Xiao

    2015-12-22

    The hydroxyl group in the spacer of a cationic Gemini surfactant (12-3OH-12) caused dramatic changes of the phase behaviors in a protic ionic liquid (EAN). Here, the effects of the hydroxyl group on micellization and lyotropic liquid crystal formation were investigated through the surface tension, small-angle X-ray scattering, polarized optical microscopy, and rheological measurements. With the hydroxyl group in the spacer, the critical micellization concentration of 12-3OH-12 was found to be lower than that of the homologue without hydroxyl (12-3-12) and the 12-3OH-12 molecules packed more densely at the air/EAN interface. It was then interesting to observe a coexistence of two separated phases at wide concentration and temperature ranges in this 12-3OH-12/EAN system. Such a micellar phase separation was rarely observed in the ionic surfactant binary system. With the increase of surfactant concentration, the reverse hexagonal and bicontinuous cubic phases appeared in sequence, whereas only a reverse hexagonal phase was found in 12-3-12/EAN system. But, the hexagonal phases formed with 12-3OH-12 exhibited lower viscoelasticity and thermostability than those observed in 12-3-12/EAN system. Such unique changes in phase behaviors of 12-3OH-12 were ascribed to their enhanced solvophilic interactions of 12-3OH-12 and relatively weak solvophobic interactions in EAN.

  12. Thermodynamics on the micellization of CPC/TX-100 mixed surfactant system in aqueous solutions of KCI

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yung Cheol [Health and Environmental Research Institute, Daegu (Korea, Republic of); Lee, Byung Hwan [Korea University of Technology and Education, Chonan (Korea, Republic of)

    2005-10-15

    The Critical Micelle Concentration (CMC) of the mixed surfactant system of CetylPyridinium Chloride (CPC) with Triton X-100 (TX-100) in aqueous solutions of KCI were determined by using the UV absorbance method from 15 .deg. C to 35 .deg. C. Thermodynamic parameters ({delta} G{sup o}{sub m}, {delta} H{sup o}{sub m}, and {delta} S{sup o}{sub m}), associated with the micelle formation of CPC/TX-100 mixed surfactant system, have been estimated from the temperature dependence of CMC values. The calculated values of {delta} G{sup o}{sub m} are all negative but the values of {delta} S{sup o}{sub m} are positive in the whole measured temperature region. On the other hand, the values of {delta} H{sup o}{sub m} are positive or negative, depending on the measured temperature.

  13. Hydrogen sulfide induces systemic tolerance to salinity and non-ionic osmotic stress in strawberry plants through modification of reactive species biosynthesis and transcriptional regulation of multiple defence pathways.

    Science.gov (United States)

    Christou, Anastasis; Manganaris, George A; Papadopoulos, Ioannis; Fotopoulos, Vasileios

    2013-04-01

    Hydrogen sulfide (H2S) has been recently found to act as a potent priming agent. This study explored the hypothesis that hydroponic pretreatment of strawberry (Fragaria × ananassa cv. Camarosa) roots with a H2S donor, sodium hydrosulfide (NaHS; 100 μM for 48 h), could induce long-lasting priming effects and tolerance to subsequent exposure to 100mM NaCI or 10% (w/v) PEG-6000 for 7 d. Hydrogen sulfide pretreatment of roots resulted in increased leaf chlorophyll fluorescence, stomatal conductance and leaf relative water content as well as lower lipid peroxidation levels in comparison with plants directly subjected to salt and non-ionic osmotic stress, thus suggesting a systemic mitigating effect of H2S pretreatment to cellular damage derived from abiotic stress factors. In addition, root pretreatment with NaHS resulted in the minimization of oxidative and nitrosative stress in strawberry plants, manifested via lower levels of synthesis of NO and H(2)O(2) in leaves and the maintenance of high ascorbate and glutathione redox states, following subsequent salt and non-ionic osmotic stresses. Quantitative real-time RT-PCR gene expression analysis of key antioxidant (cAPX, CAT, MnSOD, GR), ascorbate and glutathione biosynthesis (GCS, GDH, GS), transcription factor (DREB), and salt overly sensitive (SOS) pathway (SOS2-like, SOS3-like, SOS4) genes suggests that H2S plays a pivotal role in the coordinated regulation of multiple transcriptional pathways. The ameliorative effects of H2S were more pronounced in strawberry plants subjected to both stress conditions immediately after NaHS root pretreatment, rather than in plants subjected to stress conditions 3 d after root pretreatment. Overall, H2S-pretreated plants managed to overcome the deleterious effects of salt and non-ionic osmotic stress by controlling oxidative and nitrosative cellular damage through increased performance of antioxidant mechanisms and the coordinated regulation of the SOS pathway, thus proposing a

  14. Switchable Surfactants

    National Research Council Canada - National Science Library

    Yingxin Liu; Philip G. Jessop; Michael Cunningham; Charles A. Eckert; Charles L. Liotta

    2006-01-01

    .... We report that long-chain alkyl amidine compounds can be reversibly transformed into charged surfactants by exposure to an atmosphere of carbon dioxide, thereby stabilizing water/alkane emulsions...

  15. Enhancing plant-microbe associated bioremediation of phenanthrene and pyrene contaminated soil by SDBS-Tween 80 mixed surfactants.

    Science.gov (United States)

    Ni, Hewei; Zhou, Wenjun; Zhu, Lizhong

    2014-05-01

    The use of surfactants to enhance plant-microbe associated dissipation in soils contaminated with polycyclic aromatic hydrocarbons (PAHs) is a promising bioremediation technology. This comparative study was conducted on the effects of plant-microbe treatment on the removal of phenanthrene and pyrene from contaminated soil, in the presence of low concentration single anionic, nonionic and anionic-nonionic mixed surfactants. Sodium dodecyl benzene sulfonate (SDBS) and Tween 80 were chosen as representative anionic and nonionic surfactants, respectively. We found that mixed surfactants with concentrations less than 150 mg/kg were more effective in promoting plant-microbe associated bioremediation than the same amount of single surfactants. Only about (m/m) of mixed surfactants was needed to remove the same amount of phenanthrene and pyrene from either the planted or unplanted soils, when compared to Tween 80. Mixed surfactants (Tween 80. These results may be explained by the lower sorption loss and reduced interfacial tension of mixed surfactants relative to Tween 80, which enhanced the bioavailability of PAHs in soil and the microbial degradation efficiency. The higher remediation efficiency of low dosage SDBS-Tween 80 mixed surfactants thus advanced the technology of surfactant-enhanced plant-microbe associated bioremediation.

  16. Bending elasticity of charged surfactant layers: the effect of mixing.

    Science.gov (United States)

    Bergström, L Magnus

    2006-08-01

    Expressions have been derived from which the spontaneous curvature (H(0)), bending rigidity (k(c)), and saddle-splay constant (k(c)) of mixed monolayers and bilayers may be calculated from molecular and solution properties as well as experimentally available quantities such as the macroscopic hydrophobic-hydrophilic interfacial tension. Three different cases of binary surfactant mixtures have been treated in detail: (i) mixtures of an ionic and a nonionic surfactant, (ii) mixtures of two oppositely charged surfactants, and (iii) mixtures of two ionic surfactants with identical headgroups but different tail volumes. It is demonstrated that k(c)H(0), k(c), and k(c) for mixtures of surfactants with flexible tails may be subdivided into one contribution that is due to bending properties of an infinitely thin surface as calculated from the Poisson-Boltzmann mean field theory and one contribution appearing as a result of the surfactant film having a finite thickness with the surface of charge located somewhat outside the hydrophobic-hydrophilic interface. As a matter of fact, the picture becomes completely different as finite layer thickness effects are taken into account, and as a result, the spontaneous curvature is extensively lowered whereas the bending rigidity is raised. Furthermore, an additional contribution to k(c) is present for surfactant mixtures but is absent for k(c)H(0) and k(c). This contribution appears as a consequence of the minimization of the free energy with respect to the composition of a surfactant layer that is open in the thermodynamic sense and must always be negative (i.e., k(c) is generally found to be brought down by the process of mixing two or more surfactants). The magnitude of the reduction of k(c) increases with increasing asymmetry between two surfactants with respect to headgroup charge number and tail volume. As a consequence, the bending rigidity assumes the lowest values for layers formed in mixtures of two oppositely charged

  17. Treatment of Produced Waters Using a Surfactant Modified Zeolite/Vapor Phase Bioreactor System

    Energy Technology Data Exchange (ETDEWEB)

    Lynn E. Katz; Kerry A. Kinney; R. S. Bowman; E. J. Sullivan

    2004-03-11

    This report summarizes work of this project from October 2003 through March 2004. The major focus of the research was to further investigate BTEX removal from produced water, to quantify metal ion removal from produced water, and to evaluate a lab-scale vapor phase bioreactor (VPB) for BTEX destruction in off-gases produced during SMZ regeneration. Batch equilibrium sorption studies were conducted to evaluate the effect of semi-volatile organic compounds commonly found in produced water on the sorption of benzene, toluene, ethylbenzene, and xylene (BTEX) onto surfactant-modified zeolite (SMZ) and to examine selected metal ion sorption onto SMZ. The sorption of polar semi-volatile organic compounds and metals commonly found in produced water onto SMZ was also investigated. Batch experiments were performed in a synthetic saline solution that mimicked water from a produced water collection facility in Wyoming. Results indicated that increasing concentrations of semi-volatile organic compounds increased BTEX sorption. The sorption of phenol compounds could be described by linear isotherms, but the linear partitioning coefficients decreased with increasing pH, especially above the pKa's of the compounds. Linear correlations relating partitioning coefficients of phenol compounds with their respective solubilities and octanol-water partitioning coefficients were developed for data collected at pH 7.2. The sorption of chromate, selenate, and barium in synthetic produced water were also described by Langmuir isotherms. Experiments conducted with a lab-scale vapor phase bioreactor (VPB) packed with foam indicated that this system could achieve high BTEX removal efficiencies once the nutrient delivery system was optimized. The xylene isomers and benzene were found to require the greatest biofilter bed depth for removal. This result suggested that these VOCs would ultimately control the size of the biofilter required for the produced water application. The biofilter

  18. BINDING ISOTHERMS SURFACTANT-PROTEINS

    Directory of Open Access Journals (Sweden)

    Elena Irina Moater

    2011-12-01

    Full Text Available The interactions between surfactants and proteins shows some similarities with interactions between surfactants and polymers, but the hydrophobic amphoteric nature of proteins and their secondary and tertiary structure components make them different from conventional polymer systems. Many studies from the past about surfactant - proteins bonding used the dialysis techniques. Other techniques used to determine the binding isotherm, included ultrafiltration, ultracentrifugation, potentiometry, ion-selective electrode method and surface tension. High affinity isotherms which are typical of an anionic surfactant - protein bonding, exhibit an initial increase steep followed by a slow growth region and then a vertical growth above a certain concentration. This isotherm is typical of ionic surfactant to protein binding. Often the high affinity initial bond appears at very low concentrations of surfactant and therefore in some protein-surfactant systems, the exact shape of the isotherm in this region may be missing. The surfactant - protein binding is influenced by a number of variables such as the nature and chain length of surfactant, pH, ionic strength, temperature, nature of this protein and additives.

  19. Detergent extraction of herpes simplex virus type 1 glycoprotein D by zwitterionic and non-ionic detergents and purification by ion-exchange high-performance liquid chromatography

    NARCIS (Netherlands)

    Welling-Wester, S; Feijlbrief, M; Koedijk, DGAM; Welling, GW

    1998-01-01

    Detergents (surfactants) are the key reagents in the extraction and purification of integral membrane proteins. Zwitterionic and non-ionic detergents were used for the extraction of recombinant glycoprotein D (gD-1) of herpes simplex virus type 1 (HSV-1) from insect cells infected with recombinant b

  20. Micellar electrokinetic chromatography of aromatic anions and non-ionic aromatic compounds with stepwise changes of the concentration of cetyltrimethylammonium chloride.

    Science.gov (United States)

    Esaka, Yukihiro; Kobayashi, Miki; Murakami, Hiroya; Uno, Bunji

    2012-05-04

    Micellar electrokinetic chromatography in which the concentration of cetyltrimetylammmonium chloride (CTAC) was sequentially changed in the separation system was investigated using 10 aromatic anions and 11 non-ionic aromatic compounds as model analytes. All separations were performed in the absence of electroosmotic flow (EOF), and thus, analytes were detected in the order of their strength of interaction with micelles in the system. In isocratic elutions without EOF, the model analytes could be separated better with lower concentrations of CTAC but migration times of the analytes possessing relatively higher polarities increased markedly, and thus, long analysis times were required. Therefore, we attempted to increase the concentration of CTAC during a single measurement to reduce the analysis time without hindering the resultant separation of analytes obtained with lower concentrations. Briefly, the present surfactant stepwise elution can be performed by a sequential increase in CTAC concentrations of the running solution in the anodic reservoir from 30 to 50mM for the anions and from 20 to 50 mM for the non-ionic compounds. Additionally, to perform expected gradient separations with good reproducibility, each running solution with a different CTAC concentration was treated with tetraethylammmonium chloride as an additive to adjust electric conductivities of each running solution to be equal. Under this condition, CTAC micelles of each zone of different CTAC concentrations would migrate with practically the same velocity. Consequently, by the present stepwise method, both the 10 anionic analytes and the 11 non-ionic analytes were well separated within reasonable periods which corresponded approximately to two-third and less than half of those by the isocratic elutions, respectively.

  1. Influence of surfactants in forced dynamic dewetting.

    Science.gov (United States)

    Henrich, Franziska; Fell, Daniela; Truszkowska, Dorota; Weirich, Marcel; Anyfantakis, Manos; Nguyen, Thi-Huong; Wagner, Manfred; Auernhammer, Günter K; Butt, Hans-Jürgen

    2016-09-20

    In this work we show that the forced dynamic dewetting of surfactant solutions depends sensitively on the surfactant concentration. To measure this effect, a hydrophobic rotating cylinder was horizontally half immersed in aqueous surfactant solutions. Dynamic contact angles were measured optically by extrapolating the contour of the meniscus to the contact line. Anionic (sodium 1-decanesulfonate, S-1DeS), cationic (cetyl trimethylammonium bromide, CTAB) and nonionic surfactants (C4E1, C8E3 and C12E5) with critical micelle concentrations (CMCs) spanning four orders of magnitude were used. The receding contact angle in water decreased with increasing velocity. This decrease was strongly enhanced when adding surfactant, even at surfactant concentrations of 10% of the critical micelle concentration. Plots of the receding contact angle-versus-velocity almost superimpose when being plotted at the same relative concentration (concentration/CMC). Thus the rescaled concentration is the dominating property for dynamic dewetting. The charge of the surfactants did not play a role, thus excluding electrostatic effects. The change in contact angle can be interpreted by local surface tension gradients, i.e. Marangoni stresses, close to the three-phase contact line. The decrease of dynamic contact angles with velocity follows two regimes. Despite the existence of Marangoni stresses close to the contact line, for a dewetting velocity above 1-10 mm s(-1) the hydrodynamic theory is able to describe the experimental results for all surfactant concentrations. At slower velocities an additional steep decrease of the contact angle with velocity was observed. Particle tracking velocimetry showed that the flow profiles do not differ with and without surfactant on a scales >100 μm.

  2. Surfactant-assisted sol-gel synthesis of forsterite nanoparticles as a novel drug delivery system.

    Science.gov (United States)

    Hassanzadeh-Tabrizi, S A; Bigham, Ashkan; Rafienia, Mohammad

    2016-01-01

    In the present study, forsterite nanoparticles were synthesized via surfactant-assisted sol-gel method using cetyltrimethyl ammonium bromide (CTAB) as a surfactant. The effects of CTAB contents and heat treatment on the textural properties and drug release from nanoparticles were investigated. The synthesized powders were studied by X-ray diffraction, Fourier transform infrared spectra, Brunauer-Emmett-Teller surface area analysis and transmission electron microscope images. Mg2SiO4 materials demonstrated mesoporous characteristics and large specific surface area ranging from 159 to 30 m(2)/g. The TEM results showed that forsterite nanorods had diameters about 4 nm and lengths ranging from 10 to 60 nm. It was found that the samples with 6g CTAB show slower drug release rate than the other specimens, which is due to smaller pore size. This study revealed that the drug delivery of forsterite can be tailored by changing the amount of surfactant.

  3. Study on the Formation of Urea or Salt Induced Vesicles in Built-system Surfactant

    Institute of Scientific and Technical Information of China (English)

    Chang Gang HU; Hui XIE; Gan Zuo LI; Ya AN; Zhong Ni WANG; Xiao Yi ZHANG; Jing Ping TIAN

    2005-01-01

    The spontaneous formation of vesicles in the aqueous of cationic surfactant phosphate(PTA) and anionic surfactant sodium dodecyl sulfate (SDS) at certain mixing ratios have obtained1.The addition of urea or NaI will expand the range of spontaneous vesicle formation. The fact is demonstrated by negative-staining transmission electron microscope(TEM) and dynamic light scattering(DLS) methods. The phenomenon especially in the part of urea is reported by us at first.Mechanism of urea/NaI-induced vesicles formation is discussed from the viewpoint of the molecular geometry packing parameter f, conformation and interaction.

  4. Partitioning behavior of an acid-cleavable, 1,3-dioxolane alkyl ethoxylate, surfactant in single and binary surfactant mixtures for 2- and 3-phase microemulsion systems according to ethoxylate head group size

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Del Rio, Javier A [ORNL; Hayes, Douglas G [ORNL; Urban, Volker S [ORNL

    2010-01-01

    Partition coefficients for a pH-degradable 1,3-dioxolane alkyl ethoxylate surfactant, 4-CH{sub 3}O (CH{sub 2}CH{sub 2}O){sub 5.6}-CH{sub 2}, 2,2-(CH{sub 2}){sub 12}CH{sub 3}, 2-(CH{sub 2}) CH{sub 3}, 1,3-dioxolane or ''cyclic ketal'' surfactant, CK-2,13-E{sub 5.6,ave}, between isooctane- and water-rich phases of 2- and 3-phase microemulsion systems (K{sub n}) were determined as functions of the ethoxylate size, n, and temperature for the neat surfactant and its binary surfactant mixtures, to understand the partitioning of alkyl ethoxylates possessing a broad distribution of ethoxylate size and to determine conditions required for formation of 3-phase microemulsion systems at an optimal temperature where phase separation occurs rapidly, important for protein purification via proteins selective partitioning to the middle phase, driven by affinity to the second surfactant of the binary mixture. A semi-empirical thermodynamic mathematical model described the partitioning data well, provided optimal temperature values consistent with phase diagrams and theory, and demonstrated that the tail region of CK-2,13-E{sub 5.6,ave} is more polar than the hydrophobes of fatty alcohol ethoxylates. The addition of Aerosol-OT (AOT) removed the temperature sensitivity of CK-2,13-E{sub 5.6,ave}s partitioning, producing 3-phase microemulsion systems between 20 C and 40 C. Analysis of the bottom phases of the 2- and 3-phase microemulsion systems formed by CK-2,13-E{sub 5.6,ave} via small-angle neutron scattering demonstrated the presence of spherical, monodisperse oil-in-water microemulsions.

  5. Surfactant media for constant-current coulometry. Application for the determination of antioxidants in pharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Ziyatdinova, Guzel, E-mail: Ziyatdinovag@mail.ru [Analytical Chemistry Department, A.M. Butlerov Institute of Chemistry, Kazan (Volga Region) Federal University, Kremlyevskaya, 18, Kazan 420008 (Russian Federation); Ziganshina, Endzhe; Budnikov, Herman [Analytical Chemistry Department, A.M. Butlerov Institute of Chemistry, Kazan (Volga Region) Federal University, Kremlyevskaya, 18, Kazan 420008 (Russian Federation)

    2012-09-26

    Highlights: Black-Right-Pointing-Pointer Applicability of surfactants in constant-current coulometry is shown for the first time. Black-Right-Pointing-Pointer Reactions of antioxidants with electrogenerated titrants in surfactant media are investigated. Black-Right-Pointing-Pointer Water insoluble antioxidants can be determined in water media with addition of surfactants. Black-Right-Pointing-Pointer Coulometric determination of antioxidants in pharmaceutical dosage forms using surfactants media is developed. - Abstract: Effect of surfactant presence on electrochemical generation of titrants has been evaluated and discussed for the first time. Cationic (1-dodecylpyridinium and cetylpyridinium bromide), anionic (sodium dodecyl sulfate) and nonionic (Triton X100 and Brij{sup Registered-Sign} 35) surfactants as well as nonionic high molecular weight polymer (PEG 4000) do not react with the electrogenerated bromine, iodine and hexacyanoferrate(III) ions. The electrogenerated chlorine chemically interact with Triton X100 and Brij{sup Registered-Sign} 35. The allowable range of surfactants concentrations providing 100% current yield has been found. Chain-breaking low molecular weight antioxidants (ascorbic acid, rutin, {alpha}-tocopherol and retinol) were determined by reaction with the electrogenerated titrants in surfactant media. Nonionic and cationic surfactants can be used for the determination of antioxidants by reaction with the electrogenerated halogens. On contrary, cationic surfactants gives significantly overstated results of antioxidants determination with electrogenerated hexacyanoferrate(III) ions. The use of surfactants in coulometry of {alpha}-tocopherol and retinol provides their solubilization and allows to perform titration in water media. Simple, express and reliable coulometric approach for determination of {alpha}-tocopherol, rutin and ascorbic acid in pharmaceuticals using surfactant media has been developed. The relative standard deviation of the

  6. Synergistic effect of low-frequency ultrasound and surfactants on skin permeability.

    Science.gov (United States)

    Tezel, Ahmet; Sens, Ashley; Tuchscherer, Joe; Mitragotri, Samir

    2002-01-01

    Low-frequency ultrasound (20 kHz) and surfactants have been individually shown to enhance transdermal drug transport. In this study, we investigated the synergistic effect of ultrasound and surfactants on transdermal drug delivery. Surfactants with different head group chemistries including anionic, cationic, and nonionic with varying tail lengths (8-16-carbon atoms) were studied. We found that surfactants possessing anionic and cationic head groups were more potent than those possessing nonionic head groups in increasing skin conductivity in the presence of ultrasound. Furthermore, for surfactants possessing the same head group, those with a 14-carbon tail length were found to be most effective in enhancing skin permeability. The data presented in this report show that ultrasound and surfactants synergistically enhance skin permeability. Two mechanisms are shown to play a role in this synergistic effect. First, ultrasound enhances surfactant delivery (enhanced delivery) into the skin and, second, ultrasound disperses surfactant (enhanced dispersion) within the skin. In general, surfactants that are potent enhancers by themselves are potent enhancers in the presence of ultrasound as well. We performed imaging experiments to assess the effect of ultrasound on delivery of a model permeant, sulforhodamine B, into the skin. These experiments show that ultrasound enhances surfactant delivery and dispersion in the skin.

  7. Changes of respiratory system mechanics in ventilated lungs of preterm infants with two different schedules of surfactant treatment.

    Science.gov (United States)

    de Winter, J P; Merth, I T; van Bel, F; Egberts, J; Brand, R; Quanjer, P H

    1994-05-01

    We investigated the time course of changes in the static respiratory system compliance and resistance in relationship to surfactant administration by means of single-breath and multiple-occlusion techniques. The study comprised 12 infants receiving a high-dose schedule (200 mg/kg, maximum 600 mg/kg) and 13 infants receiving a low-dose schedule (100 mg/kg, maximum 300 mg/kg) of porcine surfactant. Eight healthy preterm infants served as a comparison group. Respiratory mechanics were studied before and at 1.5, 8, and 72 h after surfactant administration. Results were related to changes in gas transfer, including an estimate of venous admixture. Static compliance improved after surfactant instillation, and changes were similar in the two treatment groups during the first eight h (0.8 In.(hour + 1) mL.kPa-1). The compliance values remained below the values of the healthy comparison group during the whole study period, but resistance remained at the same level. There was a considerable delay in changes of respiratory mechanics in relationship to the rapid fall of the venous admixture, from 27 to 19%, and the rapid increase of the transcutaneous oxygen pressure/fraction of inspired oxygen ratio from 13 to 27 kPa within the hour. There were no clues that short-term changes in compliance were masked by breathing at a higher and flatter portion of the pressure-volume curve. Both treatment schedules resulted in a similar improvement of compliance within 72 h and the two groups benefited similarly in terms of venous admixture.

  8. BEHAVIOR OF SURFACTANT MIXTURE AT SOLID/LIQUID AND OIL/LIQUID INTERFACE IN CHEMICAL FLOODING SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Prof. P. Somasundaran

    2002-03-01

    The aim of the project is to develop and evaluate efficient novel surfactant mixtures for enhanced oil recovery. Preliminary ultra-filtration tests suggest that two kinds of micelles may exist in binary surfactant mixtures at different concentrations. Due to the important role played in interfacial processes by micelles as determined by their structures, focus of the current work is on the delineation of the relationship between such aggregate structures and chemical compositions of the surfactants. A novel analytical centrifuge application is explored to generate information on structures of different surfactants aggregates. In this report, optical systems, typical output of the analytical ultracentrifuge results and four basic experiments are discussed. Initial sedimentation velocity investigations were conducted using nonyl phenol ethoxylated decyl ether (NP-10) to choose the best analytical protocol, calculate the partial specific volume and obtain information on sedimentation coefficient, aggregation mass of micelles. The partial specific volume was calculated to be 0.920. Four softwares: Optima{trademark} XL-A/XL-I data analysis software, DCDT+, Svedberg and SEDFIT, were compared for the analysis of sedimentation velocity experimental data. The sedimentation coefficient and aggregation number of NP-10 micelles obtained using the first three softwares at 25 C are 209, 127, and 111, respectively. The last one is closest to the result from Light Scattering. The reason for the differences in numbers obtained using the three softwares is discussed. Based on these tests, Svedberg and SEDFIT analysis are chosen for further studies. This approach using the analytical ultracentrifugation offers an unprecedented opportunity now to obtain important information on mixed micelles and their role in interfacial processes.

  9. Selection and evaluation of adsorbents for the removal of anionic surfactants from laundry rinsing water

    OpenAIRE

    2007-01-01

    Low-cost adsorbents were tested to remove anionic surfactants from laundry rinsing water to allow re-use of water. Adsorbents were selected corresponding to the different surfactant adsorption mechanisms. Equilibrium adsorption studies of linear alkyl benzene sulfonate (LAS) show that ionic interaction results in a high maximum adsorption capacity on positively charged adsorbents of 0.6–1.7 g LAS/g. Non-ionic interactions, such as hydrophobic interactions of LAS with non-ionic resins or activ...

  10. TREATMENT OF PRODUCED WATERS USING A SURFACTANT MODIFIED ZEOLITE/VAPOR PHASE BIOREACTOR SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Lynn E. Katz; Kerry A. Kinney; R.S. Bowman; E.J. Sullivan

    2003-04-01

    Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. It is by some estimates the largest single waste stream in the country, aside from nonhazardous industrial wastes. Characteristics of produced water include high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component, and chemicals added during the oil-production process. While most of the produced water is disposed via reinjection, some of them must be treated to remove organic constituents before the water is discharged. Current treatment options are successful in reducing the organic content; however, they cannot always meet the levels of current or proposed regulations for discharged water. Therefore, an efficient, cost-effective treatment technology is needed. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. In addition, the low cost of natural zeolites makes their use attractive in water-treatment applications. Our previous DOE research work (DE-AC26-99BC15221) demonstrated that SMZ could successfully remove BTEX compounds from the produced water. In addition, SMZ could be regenerated through a simple air sparging process. The primary goal of this project is to develop a robust SMZ/VPB treatment system to efficiently remove the organic constituents from produced water in a cost-effective manner. This report summarizes work of this project from October 2002 to March 2003. In this starting stage of this study, we have continued our investigation of SMZ regeneration from our previous DOE project. Two saturation/stripping cycles have been completed for SMZ columns saturated with BTEX compounds. Preliminary results suggest that BTEX sorption actually increases with the number of saturation/regeneration cycles. Furthermore, the experimental vapor phase bioreactors for this project have been designed and are

  11. [Acute toxicity of different type pesticide surfactants to Daphnia magna].

    Science.gov (United States)

    Li, Xiu-huan; Li, Hua; Chen, Cheng-yu; Li, Jian-tao; Liu, Feng

    2013-08-01

    By using the standard test methods in Experimental Guideline for Environmental Safety Evaluation of Chemical Pesticide to aquatic organisms, a comparative study was conducted on the acute toxicity of 39 nonionic, 6 anionic, and 3 cationic surfactants to Daphnia magna. The acute toxicity of three cationic surfactants 1427, 1227 and C8-10 to D. magna belonged to virulent level, and the toxicity of 1427 was the highest, with the EC50 value being 0.97 x 10(-2) mg x L(-1). The acute toxicity of nonionic surfactants polyoxyethylene ether castor oil EL, Tween, and Span emulsifiers belonged to low level, but the toxicity of alkylphenol polyoxyethylene ether and fatty alcohol polyoxyethylene ether surfactants was relatively high, of which, AEO-7 and AEO-5 displayed high toxicity, with the EC50 value being 0.82 and 0.97 mg x L(-1), respectively. In these surfactants, the more liposolubility, the higher the toxicity was. Most of the anionic surfactants were medium in toxicity, but the acute toxicity of NNO belonged to high toxicity, with the EC50 value being 0.17 mg x L(-1).

  12. Use of a surfactant coacervate phase to extract trichloroethylene from water

    Energy Technology Data Exchange (ETDEWEB)

    Kimchuwanit, W.W.; Scamehorn, J.F.; Osuwan, S. [Univ. of Oklahoma, Norman, OK (United States)] [and others

    1996-10-01

    At temperatures above the cloud point, aqueous nonionic surfactant solutions can separate into two phases: a surfactant-rich coacervate phase and a surfactant-dilute phase. Since the coacervate phase can be a concentrated micellar solution, organic solute tends to concentrate in the coacervate due to solubilization. In this study, up to 90% of trichloroethylene was shown to be extracted into the coacervate phase in one stage. Increasing temperature, surfactant concentration, and added NaCl concentration all improved the fraction of TCE extracted.

  13. Study on aqueous two-phase systems of the mixture SDS/CTAB surfactants

    Institute of Scientific and Technical Information of China (English)

    LI Ying; CHEN Yah-ming; ZHAO Kong-shuang; Takumi HIKIDA

    2004-01-01

    The phenomenon of two dilute aqueous phases composed of sodium dodecylsulfate (SDS) and cetyltrimethyl ammonium bromide(CTAB) was investigated under various conditions such as concentrations and molarratios of the two surfactants, the addition of sodium chloride and temperature. Vesicles formation was found in theboth phases by TEM image.

  14. Re-entrant phase behavior of a concentrated anionic surfactant system with strongly binding counterions.

    Science.gov (United States)

    Ghosh, Sajal Kumar; Rathee, Vikram; Krishnaswamy, Rema; Raghunathan, V A; Soo