bluuebunny/crossref_metadata_2025 huggingface dataset:
Solubilization of PCBs by Surfactant Solution: Minimization of Partitioning Loss of Surfactant
Authors: Müllerová M. , Šváb M. , Vysopalová Z. , Nováková T.
Published: December 2013

Studies of solubilization of organic contaminants by surfactants are complicated by the fact that the effective surfactant concentration is decreased by partitioning into the organic phase. This paper introduces an experimental setup for surfactant solubilization where the partitioning loss of surfactants is minimized. Using this setup, two anionic (sodium dodecyl sulphate and Spolapon AOS 146) and one nonionic surfactant (Novanik 0633 A) were compared. When comparing solubilization efficacies expressed as multiples of the critical micelle concentration, the two anionic surfactants were able to solubilize a higher amount of polychlorinated biphenyls. For lower surfactant concentrations, solubilization efficacies were similar for all surfactants. However, it is necessary to take into account that the critical micelle concentration of the nonionic surfactant is considerably lower.
Highly Concentrated Cocamidopropyl Betaine – The Latest Developments for Improved Sustainability and Enhanced Skin Care
Authors: Herrwerth S. , Leidreiter H. , Wenk H. H. , Farwick M. , Ulrich-Brehm I. , Grüning B.
Published: December 2013

Today Cocamidopropyl Betaine (CAPB) is the most important secondary surfactant used in personal care and household products. Even the most modern CAPB-types still contain more water than active matter. Water which needs to be heated in the manufacturing process, which needs to be transported, and needs to be stored in storage tanks. The high water content not only contributes to the cost of production and logistics, but is also not favorable with respect to sustainability. Continuous research in the field of betaines has lead to another break-through in CAPB quality with a product containing approximately 47% active matter and less than 43% water. Thus, savings in energy consumption and shipping volume of more than 36% can be achieved as compared to the common 30% CAPB quality. The typically desired surfactant properties, the positive effects on foam and rheology could be maintained. Moreover, further improvements in quality and even additional skin care effects such as enhanced skin moisturization could be achieved.
N,N-bis-(2-Hydroxyethyl) Oleamide: Synthesis, Kinetic Study and Yield Optimization
Authors: Edrissi M. , Falamaki C. , Moradi F.
Published: December 2013

N,N-bis-(2-hydroxyethyl)oleamide (NHEO) was synthesized using oleic acid and diethanolamine in 1:1 molar ratio using orthophosphoric acid as catalyst. The reaction kinetics at 140°C has been evaluated. The latter follows a first order reaction rate which is in accordance with the reaction mechanism proposed. Yield optimization has been performed implementing an L4 Taguchi orthogonal array. The chemical analysis, rheological behavior and stabilizing ability of the product for metal and metal oxide slurries has been investigated.
Adsorption of CTAB on Zeolite A Detected by Surfactant Ion-selective Electrode
Authors: Luo Y.-Y. , Du Z.-P. , Lu Y.-H. , Liu B.-X.
Published: December 2013

Adsorption of cationic surfactant, cetyltrimethylammonium bromide (CTAB) on zeolite A has been investigated using surfactant-selective electrode technique. The electrode consisted of a polyvinyl chloride (PVC) membrane based on neutral ion-pair carrier complex of cetyltrimethylammonium tetraphenylborate (CTA+TPB−). Adsorbance of CTAB on zeolite A was calculated from the potential and concentration response characteristics of the surfactant-selective electrode to get the surfactant adsorption isotherms. Adsorption isotherm of CTAB was S-shaped. The adsorbance was related to pH and electrolyte in the surfactant solutions.
Removal of Brilliant Blue R from Aqueous Solutions on Activated Carbon Produced from Carbonaceous Substrate
Authors: Alam S. , Ahmad M. , Bangash F. K.
Published: December 2013

Adsorption of brilliant blue R on activated carbon produced from the wood of Paulownia Tomentosa was investigated. Samples characterization by XRD, SEM, EDS and FTIR showed that the oxygen containing surface functional groups (carboxyls, lactones or phenols and ethers) were present on the surface which were eliminated at 800°C. Activation at 800°C, resulted in the opening of porous structure thereby increasing the adsorption capacity. Relatively high amounts of carbon with respect to oxygen were found in the samples with the rise in activation temperature. The adsorption kinetic at 10 and 45°C showed that the first order, Bangham and parabolic diffusion models are applied to the data. The rate constant increased with the rise in temperature of adsorption/activation. Thermodynamic properties (ΔE≠, ΔH≠, ΔS≠ and ΔGo) for the adsorption process were calculated. Positive values of ΔH≠ showed that the adsorption of brilliant blue R is endothermic. Negative values of ΔS≠ reflected the decrease in the disorder of the system at the solid-solution interface during adsorption. The Gibbs free energy, which is the driving force for adsorption is negative indicating spontaneous adsorption. Freundlich and Langmuir models described the equilibrium adsorption data and Thomas model was used for the column study.
Characterization of Commercial Polysorbates Using Different Chromatographic Techniques
Authors: Abrar S. , Trathnigg B.
Published: December 2013

Polysorbates – which are commercially available under the name Tween – are complex mixtures of different functionalities. Molar mass distribution and chemical composition of various Tween samples (20, 40, 60 and 65) were determined using size exclusion chromatography (SEC) with dual detection. A separation of different functionalities was achieved using liquid chromatography under critical conditions (LCCC) on typical reversed phase columns with methanol – water and acetone – water as mobile phase. The size of the hydrophilic part was determined after microwave-assisted methanolysis, which allowed also the identification of the fatty acids bound to the hydrophilic core.
Synergism in Mixed Anionic–Amphoteric Surfactant Solutions: Influence of Anionic Surfactant Chain Length
Authors: Abdel-Rahem R.
Published: December 2013

The influence of chain length on the composition of mixed micelles in binary mixtures of N,N-dimethyldodecylamine oxide (DDAO) and sodium decyl-, sodium dodecyl- and sodium tetradecylsulfate (abbreviated as SDeS, SDS and STS, respectively) has been determined at 30°C. From the surface tension measurements, the critical micelle concentration (cmc) data were measured as a function of mixing composition. Cmc-values were then analyzed according to regular solution model. The composition of mixed micelles, the interaction parameter (β) and the activity coefficients were evaluated from the regular solution model for the all anionic-amphoteric mixed systems. The interaction parameter values indicated a synergistic interaction between DDAO and the three anionic surfactants at all mole fractions to be due to an overall attractive interaction in the mixed micelles. The strength of the interaction between the amphoteric surfactant and the sodium alkyl sulfate in three mixed systems obeys the following order: SDeS/DDAO > SDS/DDAO > STS/DDAO suggesting that the decrease in the length of anionic surfactant alkyl chain results in a stronger interaction with DDAO. On the other hand, the viscosity data reveals a viscosity increasing trend of STS/DDAO > SDS/DDAO > SDeS/DDAO.
Synthesis, Structural Properties and Applications of Gemini Surfactants: A Review
Authors: Tyagi P. , Tyagi R.
Published: December 2013

Gemini surfactants are most exciting new types of surfactants. They have two hydrophilic head groups and two hydrophobic groups in a molecule separated by a spacer group. Nowadays different types of geminis have been synthesized. Geminis show some characteristic features like low cmc, high surface activity, high solubility in water, good foaming and wetting properties, as well as low Krafft temperature. Geminis imply low eye and skin irritation. These surfactants are widely used as antifoaming and antimicrobial agents. This review paper deals with synthesis, properties and applications of various gemini surfactants.
Analysis of Surfactants by Thin-Layer Chromatography: A Review
Authors: Bhawani S. A. , Sulaiman O. , Hashim R. , Ibrahim M. N. Mohamad
Published: December 2013

Thin-layer chromatographic analysis of surfactants is presented in this review. Various chromatographic systems useful for the identification, separation and quantification of surfactants are reported. New approaches in thin-layer chromatography enable analysts to separate and determine surfactants in complex mixtures (in various environmental samples). Thin-layer chromatographic methods are mainly used for the separation of surfactants either in the separation of different classes or separation of different groups within the same class.
Studies on Acoustic and Thermodynamic Behaviour of Terbium Laurate and Myristate in Mixed Organic Solvents
Authors: Kishore K. , Upadhyaya S. K.
Published: December 2013

Ultrasonic measurements were made on terbium laurate and myristate in 60/40 benzene-methanol mixture (v/v), to determine the critical micellar concentration (CMC), ultrasonic velocity and other acoustic parameters. The results confirm that there is a significant interaction between the soap and solvent molecules. The critical micellar concentration and thermodynamic parameters for dissociation and micellization process for terbium laurate and myristate in a mixture of 60/40 benzene-methanol (v/v) at different temperature were evaluated from conductivity measurements. The results showed that these soaps behave as weak electrolytes in dilute solutions.
Adsorption and Desorption of Ionic Surfactants
Authors: Pušić T. , Grancarić A. M. , Tarbuk A. , Šauperl O. , Soljačić I.
Published: December 2013

Surfactants as organic compounds are widely used in the processes of textile finishing and care with regard to different variations and specific hydrophilic/hydrophobic character. Specific behaviour of these compounds is partly based on the adsorption process. In this study the adsorption and desorption of ionic surfactants have been studied upon the influence of fibre composition and surfactant ionogenity as well as variation of hydrophobic chain length and hydrophilic group in the molecule. Textile fibres were characterized through electrokinetic potential, sorption characteristics and swelling capacity expressed by moisture regain and water retention value (WRV). Different types of cationic and anionic surfactants were adsorbed on cotton, wool, polyester and polypropylene fibres at 20°C during 60 minutes. The quantity of adsorbed surfactants on textile fibres was determined by potentiometric titration. The textile fibres were centrifuged afterwards and the amount of surfactants was determined in the centrifugate, respectively. Drying followed at 60°C. The desorption of surfactants was performed at 20°C during 30 minutes. The results showed a correlation between amount of adsorbed, desorbed and residual surfactants and swelling capacity expressed through WRV.
Alkyl Polyglycoside-Sorbitan Ester Formulations for Improved Oil Recovery
Authors: Wu Y. , Iglauer S. , Shuler P. , Tang Y. , Goddard W. A.
Published: December 2013

We measured interfacial tensions (IFT) of aqueous alkyl polyglucoside (APG) systems formulated with sorbitan ester-type cosurfactants against n-octane. The study focused on low to ultra-low IFT systems which are relevant for enhanced oil recovery (EOR). In addition, we measured equilibrium adsorption concentrations of these surfactants and cosurfactants onto kaolinite clay, commonly found in oil reservoirs. We present one surfactant EOR laboratory flood experiment with one selected APG-sorbitan ester formulation with which we recovered 94% of initial oil in place (IOIP).
Dynamics of Formation of Vesicles Studied by Highly Time-resolved Stopped-flow Experiments
Authors: Barth A. , Grillo I. , Gradzielski M.
Published: December 2013

Phase behaviour and static structure of surfactant systems have been studied in much detail, but this applies much less so to their dynamic properties. Structural transitions in amphiphilic systems can be triggered by mixing different amphiphiles. Employing the stopped-flow technique we have studied the kinetics of formation of multilamellar vesicles starting from a micellar solution and a microemulsion containing a semipolar oil. This process has been investigated for various starting conditions and as a function of the charging of the amphiphilic system. The formation process is the faster the closer the starting solution is in composition to the final state and can be slowed down by the presence of ionic surfactant.
Comparison of Standards for Testing Electrical Dishwashers or Dishwashing Detergents
Authors: Brückner A.-K. , Stamminger R. , Bornkessel S.
Published: December 2013

This study presents an overview of four international test standards for domestic dishwashers or dishwashing detergents: the European (EN 50242), the North American (AHAM), the Australian (AS/NZS) and IKW standard. All four standards were used to test five different dishwashers and two kinds of dishwashing detergents under standardised laboratory conditions to see if they deliver comparable results. Furthermore the practicability and selectivity of the different soiling and evaluation procedures were assessed. Additionally to a general comparison of the four standards, the focus lay on the soil egg yolk. The study shows that the general ranking between the dishwashers is similar, but the cleaning results of the individual soils and the performance levels differ a lot. Only the IKW soils are suitable to make a clear distinction between the detergents. Whereas the machines can be – more or less – distinguished with all standards except AS/NZS standard. Possible reasons for the varying results can be found in the different amounts of soil, the preparation methods or the cleaning performance evaluation, which shows the importance of designing accurate testing procedures for dishwashing.
Manual Dishwashing – How can it be Optimized?
Authors: Fuss N. , Stamminger R.
Published: December 2013

The focus of this paper is to show an approach on how to optimize manual dishwashing. After presenting the method developed for simulating a repeatable manual dishwashing process, the report shows the results of the experimental study exploring the main impact factors for the optimization of the water consumption by applying a mathematical regression model. These experiments demonstrate that the water changes in the main washing bath and the water changes in the rinsing bath are significantly affecting the cleaning performance of the dishes. Concentration of cleanser is found to have a negative quadratic effect, and the interaction effect of the number of water changes in the rinsing bath with the amount of detergent (respectively Concentration of cleanser) is found to be significant. As an explanation of this behaviour, it is suspected that soil particles are transferred through foam residuals, which are not washed off in the rinsing bath. Because of several restrictions, such as having limited statistics and having excluded possible impact factors, the developed model aims at depicting tendencies of the impact factor effects and may not be generalized.
Cleaning Effect of Household Laundry Detergents at Low Temperatures
Authors: Laitala K. , Jensen H. Mollan
Published: December 2013

Lowering the washing temperature of laundry has environmental benefits, but consumers are reluctant to decrease the temperature in fear of not getting clean textiles. The objective of this study was to test eight leading laundry detergents for low temperature washing at 30°C and at 40°C. The cleaning effect was tested by measuring the reflection values of pre-soiled swatches after wash based on standard EN 60456. The results show that the difference in reflection value was on average only 1.9% higher at 40°C than at 30°C, indicating very small difference in cleaning effect. Most differences between temperatures could be seen in liquid detergents for white textiles, and least in powder detergents for coloured textiles. This confirms that modern detergents are suitable for wash at 30°C, and the soil removal will in most cases be satisfactory for household use instead of the more common wash at 40°C.
Bicontinuous Microemulsion as Reaction Medium for ω-Transaminase Catalysed Biotransformations
Authors: Laupheimer M. , Engelskirchen S. , Tauber K. , Kroutil W. , Stubenrauch C.
Published: December 2013

Due to their high enantioselectivity biotransformations, i.e. enzyme-catalysed conversion of organic compounds, are extremely attractive reactions. However, a limiting factor for choosing substrates is the enzyme-substrate incompatibility. This occurs when a hydrophilic enzyme which naturally resides in the aqueous cell cytoplasm is supposed to convert a hydrophobic substrate. In this context bicontinuous microemulsions appear to be a beneficial reaction medium for biotransformations, particularly due to their large interfacial area between a hydrophilic and a hydrophobic compound. As a “proof of concept” we performed ω-transaminase (EC 2.6.1.18) catalysed model reactions in a bicontinuous microemulsion of the type phosphate buffer/NaCl – n-octane – pentaethylene glycol monodecyl ether.
Viscosity and Percolative Phenomena in AOT based Microemulsions
Authors: Cid A. , Gómez-Díaz D. , Mejuto J. C. , Navaza J. M.
Published: December 2013

Present work includes experimental studies related to the viscosimetric behaviour of microemulsions that consist of three compounds: isooctane (organic phase), water (aqueous phase) and Aerosol OT (surfactant). The effect of the microemulsion composition, based on the ω parameter value, and the effect caused by the temperature have been analysed in this work. In relation to the influence of temperature and the use of microemulsions in different processes, one important characteristic of this kind of systems (the percolation phenomenon) must be taken into account in the discussion of the experimental results.
Synthesis and Properties of Lactobionamide-Based Polysiloxane Surfactant
Authors: Wang L. , Zhang D.-L. , Du Z.-P. , Wang G.-Y. , Wang S.-J. , Cao Y.
Published: December 2013

A lactobionamide-based polysiloxane surfactant (LBPS) with well-defined structure was prepared via a two-step method. Structure characterization of the LBPS was performed by Fourier Transform Infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H NMR). Surface activity and aggregation behavior in aqueous solution of the LBPS were investigated by surface tension measurements, dynamic light scattering (DLS) and negative-stain transmission electron microscopy (TEM). The results show that the critical micelle concentration (CMC) and surface tension (γCMC) at the CMC in aqueous solution of the LBPS are 7.7 mg · L−1and 27.5 mN · m−1, respectively, and the surfactants can self-assemble into spherical micelles with diameters in the range from 30 to 250 nm.
Structural Elucidation and Surfactant Properties of Rhamnolipids Synthesized by Pseudomonas aeruginosa (ATCC 10145) on Sweet Water as Carbon Source and Stabilization Effect on Foam Produced by Sodium Lauryl Sulfate
Authors: Wadekar S. D. , Patil S. V. , Kale S. B. , Lali A. M. , Bhowmick D. N. , Pratap A. P.
Published: December 2013

The interest in biosurfactant has increased considerably due to their large potential for industrial applications. Rhamnolipid is the simplest class of biosurfactants with well defined structure. The main obstacle in commercialization of biosurfactant especially rhamnolipids is the higher cost of the production that can be reduced by use of inexpensive carbon substrates like glycerol that is readily available from commercial fat-splitting process in the form of sweet water (up to 20% w/v) at very low cost. The composition and structure of various components in crude rhamnolipids synthesized by of Pseudomonas aeruginosa (ATCC 10145) on sweet water, were determined using TLC, HPLC and LC\MS. The crude product showed two distinct components having structure Rha2C10C10 and Rha2C10C12 at 85.45 wt.% and 14.55 wt.% respectively. The Rha2C10C10 was more efficient and effective in surface tension reduction up to 23.5 mN/m than other components. Crude rhamnolipids showed better emulsifying power than its individual components. The crude rhamnolipids showed better foam stability than sodium lauryl sulfate (SLS) at lower concentrations (0.05 to 0.002% w/v). It also enhanced and stabilized the foam produced by SLS at 0.01 to 0.025% of rhamnolipids.
Experimental Study of Surfactant Retention on Kaolinite Clay
Authors: Wu Y. , Iglauer S. , Shuler P. , Tang Y. , Goddard W. A.
Published: December 2013

We measured equilibrium surfactant retention on kaolinite clay for a large array of surfactants. We demonstrate that the mass balance measurements we used are a rapid way to screen surfactants in terms of their potential to be used in enhanced oil recovery applications. Surfactant classes investigated include: alkyl(aryl) sulfonates, ethylene oxide-propylene oxide copolymers, ethoxylated alkylphenols, alkyl polyglucosides, sorbitan ester ethoxylates, alkyl alcohol propoxylated sulfate sodium salts, gemini surfactants, sulfosuccinates and organo silicone-ethylene oxide-propylene oxide terpolymers. We identified several surfactants which had zero retention under the test conditions and which may therefore be suitable as enhanced oil recovery chemicals in surfactant flooding schemes. We discuss surfactant retention mechanisms on kaolinite clay and analyze surfactant structure-retention relationships for several surfactant classes.
Resource Saving by Training – How much can be Saved in Manual Dishwashing?
Authors: Fuss N. , Stamminger R.
Published: December 2013

Automatic dishwashing has been optimised in manifold ways during the last decades. But it is also necessary to optimise manual dishwashing, because almost every household still washes up at least a few items by hand. A procedure based on an experimental multi-factorial laboratory study was developed to wash up a specified number of dishes with good cleanliness and an optimum water consumption as results. This procedure was then translated into generalised dishwashing tips – called Best Practice Tips. These tips were used to run two comparative consumer laboratory studies: the first part of each study investigated the everyday dishwashing behaviour and resource consumption of consumers. The second part studied the behaviour and the resource consumption after a training on the Best Practice Tips. The comparison showed that with a larger number of dishes, relevant amounts of resources of energy and water can be saved, whereas with a smaller number of dishes, no significant reduction was found. This is possibly due to a different optimum for washing up only a few items.
Effect of Some Non Functional Surfactants and Electrolytes on the Hexavalent Chromium Reduction by Glycerol: A Mechanistic Study
Authors: Basu A. , Ghosh S. K. , Saha R. , Nandi R. , Ghosh T. , Saha B.
Published: December 2013

Hexavalent chromium is a widespread environmental contaminant and a known human carcinogen. Kinetics of reduction of hexavalent chromium by bio-molecule glycerol in micellar media have been studied spectrophotometrically. The cytoplasmic reduction of hexavalent chromium to trivalent chromium occurs in micro-heterogeneous systems. In vitro, the micelles are considered to mimic the cellular membranes. The electron transfer processes occurring in the micellar systems is considered as model to obtain insight into the electron transport process prevailing in biological systems. Micellar media is also a probe to establish the mechanistic paths of reduction of hexavalent chromium to trivalent chromium. Effects of electrolytes common to biological system are studied to establish the proposed reaction mechanism strongly.
Artificial Intelligence for Electrical Percolation of AOT-based Microemulsions Prediction
Authors: Cid A. , Astray G. , Manso J. A. , Mejuto J. C. , Moldes O. A.
Published: December 2013

Different Artificial Neural Network architectures have been assayed to predict percolation temperature of AOT/i-C8/H2O microemulsions. A Perceptron Multilayer Artificial Neural Network with five entrance variables (W value of the microemulsions, additive concentration, molecular weight of the additive, atomic radii and ionic radii of the salt components) was used. Best ANN architecture was formed by five input neurons, two middle layers (with eleven and seven neurons respectively) and one output neuron. Root Mean Square Errors (RMSEs) are 0.18°C (R = 0.9994) for the training set and 0.64°C (R = 0.9789) for the prediction set.
Study of Interfacial Tension in an Acid-Free Oil/Alkali/Surfactant System
Authors: Liu B. X. , Hou J. R. , Wang Y. , Tang H. J. , Lv Z. B.
Published: December 2013

Experimental studies have been conducted to explore the interfacial tensions in an acid-free oil/alkali/surfactant system, and sodium hydroxide is used as the alkali chemical. The influences of salt and alkali on the interfacial activity of oil/surfactant systems were studied by the measurement of interfacial tensions and partition coefficients. The results showed that in an appropriate concentration range, an ultra-low interfacial tension could be obtained in the acid-free oil/alkali/surfactant system, and compared with the salt; the function of alkali for lowering interfacial tensions and improving partition coefficients is more significant.
Reduction of Methylene Blue by Ascorbic Acid: Kinetic and Thermodynamic Aspects
Authors: El-Aila H. J.
Published: December 2013

This article reports the reduction of methylene blue (MB) by ascorbic acid (H2As) in basic aqueous and micellar solutions. Ascorbate ion (As2–) is found to be an effective reducing agent for the decolorization of methylene blue under ambient condition. Effects of salting-in and salting-out agents have been investigated for real-time application in the reduction process. The salting-in agent urea has been found to uniquely enhance the rate of the reduction of MB by As2– in the presence of micelles. Detailed kinetic and thermodynamic aspects have been considered to realize the interaction between methylene blue and ascorbate ion. Kinetic studies revealed that the reaction follows pseudo first order reaction kinetics.
Synthesis and Properties of a New Tetrasiloxane-tailed Dicephalic Surfactant
Authors: Zhang Dianlong , Wang Changhong , Wang Guoyong
Published: December 2013

A new tetrasiloxane-tailed dicephalic surfactant was synthesized. The structures of intermediate and product were confirmed by infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy. Surface activity and wetting ability of the surfactant were also investigated. The results show that the prepared surfactant exhibited excellent surface activity reducing the equilibrium surface tension of water to a minimum value of approximate 21.8 mN · m−1.
Lyotropic Liquid Crystals Formed in Brij35/Copolymer/Water System
Authors: Wang Zhongni , Liu Feng , Zhang Tandong , Wei Xilian , Zhou Wu , Tang Xiaolu
Published: December 2013

Phase diagram of poly (ethylene oxide)-poly (propylene oxide)-poly (ethylene oxide) copolymer (AL-64) and nonionic surfactant dodecyl polyoxyethylene (23) ether (Brij 35) aqueous solutions has been determined at 25°C using the titration method. Hexagonal, cubic and two lamellar liquid crystalline phases were found and characterized by use of polar optical microscopy and small-angle X-ray scattering (SAXS) techniques. Dynamic rheological measurements were further performed on the found liquid crystals. It has been shown that the cubic and lamellar phases exhibit elastic properties, while the hexagonal phase presents viscoelastic properties. At the constant water content, with increase in the concentration of the copolymer AL-64, the rheological G′ and G″ moduli, the critical shear stress and the network strength of the hexagonal liquid crystals get decreased. The two lamellar phases exhibit clearly different rheological properties, and the lamellar phase lies in Brij35 rich side possess stronger network strength than the hexagonal phase, through the rheological data analyses.
Investigations in the Stranski-Laboratorium of the TU Berlin – Physical Chemistry of Colloidal Systems – Going Towards Complexity and Functionality
Authors: Altin Burcu , Barth Anina , Bressel Katharina , Chiappisi Leonardo , Dürr Max , Dzionara Michaela , Elgammal Mahmoud , Fliegner Daniela , Ganas Caroline , Gupta Sakshi , Hedicke Gabriele , Heunemann Peggy , Hoffmann Ingo , Joksimovic Rastko , Kaur Ravneet , Klee Andreas , Liu Hsin-yi , Lutzki Jana , de Molina Paula Malo , Medebach Martin , Michel Raphael , Muthig Michael , Nguyen-Kim Viet , Oppel Claudia , Prévost Sylvain , Popig Jens , Riemer Sven , Sperling Marcel , Strassnick René , Zhang Lin , Gradzielski Michael
Published: December 2013

The research topics of our group are in general from the field of physical chemistry of colloidal systems. Within this rather wide layout a large variety of quite different questions and systems are tackled, where the common bridging factor is the aim of understanding the properties of colloidal systems based on their mesoscopic structure and dynamics, which in turn are controlled by their molecular composition. With such an enhanced understanding of the correlation between mesoscopic structure and the macroscopic properties the goal then is to employ this knowledge in order to formulate increasingly complex colloidal system with correspondingly more variable and interesting functionalities. From this general context of investigations, some representative systems and questions that have been studied in recent time by us are covered in this text.

They comprise the phase behaviour and the structures formed in solutions of surfactants and amphiphilic copolymers. Once these static properties are known, we also have a high interest in the dynamic properties and the kinetics of morphological transitions as they are observed under non-equilibrium conditions, since they are frequently encountered in applications. A key property of amphiphilic molecules is their ability to solubilise sparingly soluble compounds thereby forming microemulsions or nanoemulsions, where the ability to form such systems depends strongly on the molecular architecture of the amphiphiles. By turning to polymeric amphiphiles the concept of surfactants and their architecture can be extended largely towards more versatile structures, more complex self-assembly and much larger length and time scales. Another direction is the surfactant assisted formation of nanoparticles or mesoporous inorganic materials. By combining copolymers with other polymers, copolymers, colloids, or surfactants – for instance via electrostatically driven co-assembly – one may then form increasingly complex colloidal aggregates. By doing so one is able to control rheological properties or develop complex delivery systems, whose properties can be tailor-made by appropriate choice of the molecular build-up. This striving towards well controlled complexity achieved by means of self- and co-assembly then leads to increasingly more functional systems and is the key direction for future research activities in our group.
Study of Micelle Properties and Thermodynamics of Micellization of the Benzethonium Chloride
Authors: Oremusová Jarmila , Vitková Zuzana , Vitko Anton
Published: December 2013

The self-association of benzethonium chloride (BZCl) in aqueous solution has been analyzed as a function of temperature. The critical micelle concentration (CMC.), the degree of counterion binding (β) and thermodynamic parameters of micellization (molar Gibbs energy, enthalpy and entropy of micellization) were determined using six experimental methods (conductometry, potentiometry, UV spectrophotometry, spectrofluorimetry, NMR and densitometry) within the temperature range 20–50°C. All methods used gave very similar values for CMC. Changes in the thermodynamic parameters on micellization were determined by applying a mass action model.
Synthesis and Properties of Sodium Mono-alkylamide Maleate Surfactants
Authors: Han Fu , Xu Bao-cai , Qu Zhi-qiang , Zhou Ya-wen , Zhang Gui-ju
Published: December 2013

The synthesis of a series of sodium mono-alkylamide maleate surfactants was described, and the surface activity properties of the surfactants were studied. The mono-alkylamide maleic acids were synthesized by amidation using primary aliphatic amine (lauryl, myristyl, cetyl) and maleic anhydride as starting material. They were structurally characterized by IR, 1H-NMR and MS. The sodium mono-alkylamide maleate surfactants were prepared by neutralization of the precursor mono-alkylamide maleic acids with sodium hydroxide. They reduced the surface tension of water to 32–34 mN · m–1 at concentration levels of 10–4–10–3 mol · L–1.
Troubles with the Solution: Fabric Softeners and Odour Properties
Authors: Laitala Kirsi , Kjeldsberg Marit , Klepp Ingun Grimstad
Published: December 2013

Fabric softeners are mainly used to reduce roughness and static electricity of textiles, as well as adding a scent to them. In this paper we study how fabric softeners are related to odour properties on clothing. We combine a Norwegian consumer survey with a sensory test on odour development on four different materials used in sports clothing. Samples went through several cycles of use with sweating, washing, and airing and the odour was evaluated at 11 stages. Washing was performed either with or without a fragrance-free domestic rinse cycle softener. Sensory test showed that use of softener increased odour on polyester garments. Survey results showed that a larger number of respondents who used softeners experienced problematic odours in laundry compared to those who did not use softeners.
Removal of Synthetic Organic Foulants by Granular Activated Carbon Filters and Ultrafiltration Membrane
Authors: Zahoor Muhammad
Published: December 2013

In this study granular activated carbon (GAC) was used as pretreatment for foul control in ultrafiltration (UF) membrane process. First the adsorptive parameters for phenol, chlorophenol, nitrophenol and hydroquinone on GAC were determined. The equilibrium data fits well to Langmuir adsorption isotherm rather than Freundlich model. Breakthrough curves were obtained from fixed bed experiments and column parameter were calculated from it. GAC filters were then used in combination with UF membrane system. The percent retentions of the four organic substances under study were determined and the declines in flux were observed. The problems associated with powdered activated carbon like cake formation over membrane surface, long back wash time and blackening of pipes were not observed for GAC.
Immobilized Micro-Organism in Mesoporous Activated Carbon for Treatment of Tannery Waste Water
Authors: Sekaran Ganesan , Karthikeyan S. , Mandal Asit Baran , Gupta Vinod Kumar
Published: December 2013

Chemo-Autotrophic Activated Carbon Oxidation (CAACO) system was used for the treatment of tannery waste water. It employs activated carbon-immobilised sulphate reducing bacteria for the removal of dissolved organics in wastewater under oxidizing environment. The wastewater characteristics such as COD (1689 mg/L), BOD (377 mg/L), sulphate (915 mg/L) and sulphide (184 mg/L) were applied at an hydraulic loading rate of 0.7376 m3/m3/day and surface loading rate of 0.2438 m3/m2/day to CAACO reactor at 30°C and at atmospheric pressure. The removal of COD, BOD, sulphide and sulphate was 87%, 96%, 100% and 40% respectively after 2 hours of oxidation. The oxidation of dissolved organics in wastewater was accomplished by passing air at flow rate 3 L/min and at pressure 0.5 kg/cm2through CAACO reactor. The effect of variables COD loading, O2/COD, O2/(COD-BODL), COD/S2–, (COD-BODL)/S2– and [(COD-BODL)i–(COD-BODL)e]/S2– on rate and percentage removal of COD from tannery wastewater was determined.
Kinetic Studies of Glutamic Acid Oxidation by Hexavalent Chromium in Presence of Surfactants
Authors: Basu Ankita , Ghosh Sumanta Kr. , Saha Rumpa , Ghosh Aniruddha , Ghosh Tuhin , Mukherjee Kakali , Bhattacharyya Subhendu Sekhar , Saha Bidyut
Published: December 2013

Hexavalent chromium is a widespread environmental contaminant and a known human carcinogen. It is a very important to remove toxic Cr(VI) from industrial waste water. In human body Cr(VI) is reduced to Cr(III). Effective bio-molecule present in body contains a number of different functional groups. Kinetics of reduction of Cr(VI) by an important amino acid, glutamic acid in micellar media have been studied spectrophotometrically. Micellar media is a testing enviroment to establish the mechanistic paths of reduction of Cr(VI) to Cr(III). The catalyst and suitable surfactants enhance the reduction of Cr(VI).
Synthesis and Surface Properties of CO2H Type Gemini Surfactant Having Semifluoroalkyl Group as Hydrophobic Group
Authors: Kawase Tokuzo , Ankyu Tomoyuki , Oida Tatsuo
Published: December 2013

Novel CO2H type gemini surfactants having semifluoroalkyl group (Rf-(CH2)n-: Rf = C4F9, C6F13, C8F17 and n = 2, 3) as hydrophobic group were successfully synthesized and their surface properties were studied. (Perfluoroalkyl)ethylmalonic esters were synthesized by the reaction of malonic ester with Rf(CH2)2I using NaH as base in THF/DMF. (Perfluoroalkyl)propylmalonic esters were synthesized from allylmalonic ester, namely by the radical addition of Rf-I using AIBN as initiator, and reduction with Zn/AcOH. Those fluoroalkylated malonic esters were connected using Br(CH2)sBr (s = 3, 4) to give dimeric tetraesters. Then, tetraesters were hydrolyzed using KOH/EtOH followed by decarboxylation in AcOH to afford CO2H type gemini surfactants. To study their surface properties, both surface tension-concentration and surface pressure-area isotherms were measured. As expected, COOH geminis showed one order of magnitude lower critical micellar concentrations (CMC) than that of conventional 1+1 type surfactant. In the surface pressure-area measurements, as length of fluoroalkyl increased, lift-off area (AL) decreased, monolayers were clearly formed upon compression and the limited areas (A∞) for C6F13 and C8F17 were smaller than twice of that of C8F17(CH2)2COOH. Especially, COOH geminis having Rf = C8F17 and -(CH2)3- spacer showed the formation of solid phase monolayers, and the planar five membered ring-like structure was proposed.
Synthesis and Performance of Polyoxy-ethylene Ester Quaternary Ammonium Salt
Authors: Sun Yong-Qiang , Li Wen-Jing , Wang Wan-Xu , Li Qiu-Xiao , Hreczuch Wieslaw , Sulek Wlodzimierz
Published: December 2013

A novel polyether esterquat (EQDMS-3EO) was obtained by ethoxylation followed by quaternization of an ester-amine. Its structure and performance were examined. The softening, antistatic, rewettability properties and fabric whiteness impact were determined and compared to conventional esterquat compounds, known from the art in the field. The results showed that antistatic and rewettability properties of the EO-modified EQDMS-3EO were better than those of the conventional counterparts, and its softening property was comparable or better. As a result, EQDMS-3EO is a new softener with superior properties.
The PVP/VI Copolymer Dye Transfer Inhibition Agent During the Washing of the Polyester Fabric
Authors: Carrión-Fité Francisco J.
Published: December 2013

The objective of this research was to study the effect of the copolymer polyvinylpyrrolidone/vinylimidazole (PVP/VI) for use as a dye transfer inhibitor (DTI) during the washing of dyed polyester fabric, depending on the detergent components. The DTI was used to find its efficiency during repeated washings of polyester fabric dyed with disperse dyes. At the same time, its efficiency was tested for preventing dye migration to other fabrics, such as polyester, cellulose diacetate, acrylic, polyamide, cotton and wool. The influence of anionic (SDBS) and non-ionic (alkyl ethoxylates with 6 EO-groups) surfactants in different proportions and with zeolite as a builder and the aforementioned DTI was tested. Results of CIELAB colour differences were obtained for the dyed and undyed polyester fabrics after five washings.
Biodegradation of Alcohol Ethoxylates by Bacterial Consortium from Industrial Wastewater
Authors: Nowicka Dorota , Budnik Irena , Zembrzuska Joanna
Published: December 2013

Industrial waste water, can contain pollutions such as inorganic water-insoluble substances (in particular sewage from electroplating). In nature, the microorganisms play a special role in maintaining life on earth. The decomposition of organic compounds into simple minerals is the main link in the circulation of biogenic elements, especially carbon, nitrogen, phosphorus, sulfur and other. The aim of the study was to evaluate the biodegradability of a model nonionic surfactant and identification of metabolites generated in the process of biodegradation using microbial consortium originating from electroplating wastewater. Tested model nonionic surfactant C12E10 is a mixture of polydisperse homologues of C12Ex, C14Ex and C16Ex series. Alcohol ethoxylates were isolated by liquid-liquid extraction (LLE) using chloroform. Aliquot of the extract was evaporated and reconstituted in the mobile phase for further LC-MS analysis.
The Effect of Electrolytes on the Interaction of C. I. Reactive Orange 16-Tetradecyltrimethylammonium Bromide
Authors: Akbaş Halide , Taner Tanzer
Published: December 2013

The aim of this study is to investigate the interaction of a cationic surfactant tetradecyltrimethyl ammonium bromide (TTAB) on the electronic absorption spectra of azo dye Reactive Orange 16 (RO16) and to observe the effects of the kind and concentration of electrolytes on these interactions by means of UV-Vis spectroscopy in submicellar and micellar concentration range at a certain temperature (303 K). TTAB affects the electronic absorption spectra of dye solution that is dye-surfactant interaction results into formation of complex and therefore, a decrease in maximum absorption spectra (1.577 at 494 nm). The electrolyte anions cause an increase on the absorbance of TTAB–RO16 ion-pair complex in the following order: Br– > Cl– > SO42– > NO3– > CN– and also for cations; Na+ > K+ > NH4+ > Mg2+. The increase or decrease on absorption spectra of RO16-TTAB solution depends on concentration range of the electrolyte added.
Study of Surface Active Characteristics of Developed Detergent for Fur Treatment
Authors: Lutfullina Gulnaz Gusmanovna , Abdullin Ildar Shaukatovich , Bujanova Anna Gennadievna
Published: December 2013

The physicochemical and colloid-chemical characteristics of a developed detergent were studied. Due to synergism of surfactants of different nature the wetting and emulsifying ability as Well as the detergency of the developed detergent are very high.
Washing Wool with Surfactants and a Non-toxic Solvent Microemulsion: Influence of Water Hardness
Authors: Carrión-Fité Francisco J.
Published: December 2013

In this work, detersive power (soil removal) was studied after washing a soiled wool fabric with addition of a non-toxic solvent microemulsion to conventional washing detergent formulations with the aim of improving the performance of the conventional washing. The non-toxic solvent used was dimethyl sulfoxide micro-dispersed with an amphoteric surfactant as emulsifier. The fabric was washed with biodegradable non-ionic surfactants such as an alcohol ethoxylate (AE) with 7 m E. O. and an alkyl polyglucoside with 1.4 glucoside groups (APG). The fabric used was EMPA 107 wool (soiled with standard impurities). The non-ionic surfactants were used separately and in mixture in varying proportions for the washes. Given the large amount of impurities in the wool fabric, sodium carbonate and sodium chloride were used to attain a suitable pH to avoid damaging the wool. The fabric was washed at low temperature with water of different hardness (20 °hf, 30 °hf and 40 °hf). In addition, the sequestering agent DTPMP was used to obtain an improvement of detersive power at the hardness of 40 °hf.
Stabilization of Foam Produced by Sodium Lauryl Sulphate with Mannosylerythritol Lipids Synthesized on Soybean Oil and Sucrose byPseudozyma antarctica(ATCC 32657)
Authors: Bhangale Akash , Patil Sachin , Wadekar Sushant , Kale Sandeep , Lali Arvind , Bhowmick Diptinarayan , Pratap Amit
Published: December 2013

Biosurfactants are gaining importance due their large potential for industrial applications and their eco-friendly nature. The properties of biosurfactants can vary with their structure which is dependent upon strain, cultivation conditions and carbon source. A mannosylerythritol lipid (MEL) is one of the simplest biosurfactants with a well-defined structure produced by Pseudozyma antarctica (ATCC 32657). The study includes the surfactant properties of MEL produced on soybean oil with sucrose as substrate. MEL showed surface activity at very low concentrations. The various properties were explained on the basis of the structural similarity between MEL and Gemini surfactant. The performance properties of SLS like foaming, emulsification and wetting were improved when SLS was partially substituted (5–20 %) by MEL. Based on the study, MEL can be used in various cosmetic products like shaving creams, skin creams and lotions, where MEL will not only enhance foaming property but also provide moisturizing and healing properties on skin.
Predicting Critical Micelle Concentration Values of Non-Ionic Surfactants by Using Artificial Neural Networks
Authors: Astray Gonzalo , Iglesias-Otero Manuel A. , Moldes Oscar A. , Mejuto Juan C.
Published: December 2013

Critical Micelle Concentration is a fundamental property on studying behaviour of surfactants. In general terms it depends on temperature, pressure and on the existence and concentration of other surface-active substances and electrolytes. In this work it is presented a model based on Artificial Neural Networks to obtain predictive values of Critical Micelle Concentration (CMC) of some non-ionic surfactants. ANN model works using topological descriptors of the molecules involved together with already known CMC values and provides predictive values for new cases. It is proposed a specific architecture for ANN consisting of an input layer with seven neurons, one intermediate layer with fourteen neurons and one neuron in the output layer. This ANN model seems to be a good method for forecast CMC.
Research the Oil Displacing Performance of Dodecyl Polyoxyethylene Ether Sulfonates at Difficult Conditions
Authors: Chen Lifeng , Zhang Xingkai
Published: December 2013

This paper evaluated the oil displacing performance of novel surfactants called dodecyl polyoxyethylene ethers sulfonates (AESO) at high-temperature, high-salinity and low-permeability reservoir conditions. We found that AESO-9 and AESO-12 with better thermal stability could create ultra-low interfacial tension (IFT) at high-temperature and high-salinity conditions, and the IFT was largely independent of both temperature and salinity. Compared to AES-12, temperature and salinity had much less effect on the emulsification property of AESO-12. The dynamic equilibrium adsorption capacity of AESO-12 was only 0.09 mg/g sand at 90 °C. The incremental recovery by only using AESO-12 could attain 8.81 % at difficult conditions. When the core permeability decreased to 2.67 × 10−3 μm2, the incremental recovery by using the composite oil displacement agents based on AESO-12 could still attain 10.98 % at the temperature of 90 °C and the salinity of 60 g/L. In brief, AESO-12 exhibits excellent oil-displacement capacity at high-temperature, high-salinity and low-permeability reservoir conditions.