表面活性剂溶液润湿行为研究进展

润湿是指溶液在固体表面的铺展过程。本文主要从溶液铺展能力、表面活性剂吸附和固体表面性质等三个方面综述了表面活性剂溶液在固体表面的润湿行为及其研究和进展。     

Influence of Nonionic Surfactant on Hydrolysis of Vinyl Sulfone Reactive Dye

Nonionic surfactants are widely used in reactive dyeing processes, and the interaction between surfactants and reactive dyes affect the hydrolytic property of reactive dyes. In this study, reactive brilliant blue KN‐R (C.I. reactive blue 19) was employed as a model dye, and fatty alcohol polyoxyethylene ether (AEO‐9) was selected as a model nonionic surfactant. The interaction was first investigated in aqueous solutions by a UV‐spectrophotometry method, then the effect of surfactant concentration on the hydrolytic behavior of KN‐R was studied using high performance liquid chromatography method. Below the critical micelle concentration, the surfactant served as dispersant; the hydrolysis of reactive dye was accelerated. However, when the concentration of surfactant was above its critical micelle concentration, the dye was solubilized into the micellar phase, which was revealed from the changes in absorbance intensity and wavelength of the maximum absorbance. This led to slowed hydrolysis of reactive dye. These findings are useful in understanding the effect of concentration of nonionic surfactant on the hydrolysis of vinyl sulfone reactive dyes.     

In‐Situ Formation of Viscoelastic Wormlike Micelles in Mixtures of Non‐Surface‐Active Compounds

Viscoelastic fluids based on surfactant self‐assembled wormlike micelles have been in focus over the past decade. In this work, we report wormlike micellar solutions formed in situ by simply mixing two non‐surface‐active compounds, N‐(3‐(dimethylamino)propyl)palmitamide (C16AMPM) and salicylic acid (HSal), without specialized organic synthesis of a surfactant. In the absence of HSal, C16AMPM is poorly soluble in pure water; after introducing HSal, C16AMPM is protonated into quaternary ammonium, behaving like a cationic surfactant with a low critical micellar concentration (0.25 mM) and a small area per molecule, which favors the formation of long cylindrical wormlike micelles. Above the overlapping concentration (~28 mM), the wormlike micelles formed entangle each other into viscoelastic networks, enhancing the viscosity by several orders of magnitude. In contrast to the worms formed by a single ultra‐long‐chain surfactant, the current system shows the advantages of a smaller flow activation energy and end‐cap energy, simpler formulation and lower cost, which make it more suitable for practical use.     

Treatment of Aqueous Ionic Surfactant Solutions by Dynamic Ultrafiltration

Abstract

This paper investigates the reduction of concentration of an ionic surfactant (sodium dodecyl benzene sulfonate) present in an aqueous solution by ultrafiltration. A dynamic filtration system consisting of a metal disk rotating near a flat circular organic membrane was used in this study. Membranes cut off tested were 10, 20, and 50 kDa. The maximum rejection rate was 92% at 10 kDa. Permeate fluxes kept increasing with transmembrane pressure until at least 1400 kPa, reaching 400 Lh^?1m^?2 at 10 kDa and 950 at 50 kDa for a rotation speed of 1000 rpm. However, raising the rotation speed above 500 rpm at 900 kPa had only a moderate effect on performance, indicating probably strong interactions between surfactant molecules and the membrane and that the permeate flux was mostly limited by pressure.     

Separation of Organic Compounds from Surfactant Solutions: A Review

Abstract

This review summarizes the recent development in separation of emulsified organic compounds from surfactant solutions for surfactant reuse and/or surfactant‐contaminant disposal. Three major principles have been employed for separating organic compounds and/or surfactants from aqueous solutions, namely, organic compound inter‐phase mass transfer, surfactant micelle removal, and manipulation of surfactant solution phase behavior. Details of these principles and their applications are discussed, with the advantages and limitations of each separation method compared. Separation based on mass transfer of the organic compounds into a secondary phase is currently more practical than the others. Finally, two major issues requiring further research are identified.     

Solubilization Behavior of Phorbol Esters from Jatropha Oil in Surfactant Micellar Solutions

Phorbol esters (PEs) are important toxic compounds found in Jatropha curcas oil and pressed seeds. These compounds are tumor promoters; thus, their removal prior to further utilization of the pressed seed is important. This work aimed to investigate the solubilization behavior of PEs and Jatropha oil in nonionic [effect of the ethylene oxide number (EON), carbon‐chain length and temperature] and anionic (NaCl addition) surfactant systems. The results reveal that an increase in the EON of the nonionic surfactant molecules, rather than an increase in the carbon‐chain length, enhances PE solubilization. The hydrophile‐lipophile balance (HLB) value was correlated with PE solubilization for nonionic surfactant solutions. The solubilization of PEs decreased slightly with increasing temperature, in contrast to solubilization of the oil. Moreover, the mole fraction of PE solubilized in the micelle decreased with increasing electrolyte concentration in anionic surfactant solutions. The solubilization behavior of PEs in both nonionic and anionic solutions indicates that PE acts more like a polar compound than a nonpolar compound. In addition, the PEs in nonionic micelles are likely located in the palisade region (i.e., between the head group and the first few carbon atoms of the tail), whereas those in anionic micelles are likely near the outer core of the head group. This finding suggests that a nonionic surfactant with a higher EON has a greater potential to extract PE from Jatropha seeds. If an anionic surfactant is combined as co‐surfactant, a small amount of electrolyte should be added to increase PE solubilization.     

Surfactant Effects on Aeration Performance of Stirred Tank Reactors

The effect of surfactants on aeration performance in stirred tank reactors (STR) at high rates of foaming is studied. The volumetric oxygen transfer coefficient (k_La) and foaming activity estimated as foaming height (H_f) were determined. Biotechnology of lipopeptide biosurfactants from aerobic organisms, e.g., Bacillus subtilis were addressed. Using model solutions of known foam‐generating properties, high‐molecular weight surfactin and low‐molecular weight sodium dodecyl sulphate (SDS), as well as impellers of different types, with flat and fluid‐foil blades, clues on the concentration dependence of STR oxygen transfer and foaming as well as options for foam reduction in the presence of biosurfactant were sought. In response to a two‐fold decrease of surface tension by surfactin, k_La values decreased up to 30 % but remained within the range expected for the mixing system in water; the experiments with SDS showing stronger dependence on surfactant concentration and surface tension. Mixing of surfactant media by a standard six‐blade disc turbine (RT) imposed rate limitations on gassing. A low‐shear impeller Narcissus (NS) could be used to avoid bulk foam outflow, while preserving k_La values that remained unchanged. The ‘power per unit volume' correlation of k_La in stirred tanks is tested in the presence of surfactin.     

Influence of Temperature on the Surface Tension of Triton Surfactant Solutions

The surface tension of different Triton surfactants (X-100, X-405, and X-705) with or without adding sodium chloride was measured in the temperature range between 20 and 40°C using the maximum bubble pressure method. Rising temperature reduced the surface tension of Triton surfactants via disrupting the H-bonds between the ethylene oxide (EO) group and water. Increasing the number of the EO groups created the steeper thermal gradient of the surface tension. The data indicated that EO-water bonds are easier to be broken by rising temperature than the water–water H-bonds, with an entropy change of −0.535 J deg⁻¹ per mole of EO. The presence of NaCl decreased the surface tension for all systems. However, NaCl produced a synergistic effect with surfactants on the surface tension.     

干涉测量法测定蔗糖溶液的扩散系数D以及表面活性剂对D值的影响

用干涉测量法测定了若干条件下蔗糖溶液的扩散系数Ｄ。并测定了表面活性剂对Ｄ值的影响。当温度为１５．５℃（室温）时，浓度为５％的蔗糖溶液的Ｄ值为４．６２×１０~（－６）ｃｍ~２／ｓ。相同条件下含有１％表面活性剂的蔗糖溶液的Ｄ值为３．７３×１０~（－６）ｃｍ~２／ｓ。结果表明表面活性剂可降低蔗糖溶液的Ｄ值。     

甜菜碱型表面活性剂的合成研究

面对日新月异的经济发展,能源需求也面临严峻的考验。在现有的能源资源中,石油是重要的品种之一,在世界各国中已然占据了特殊重要的地位。因而,为了确保主力油田在进入水驱末期以后依然可以维持稳产、高产,以包括化学剂驱油和热力采油技术等为主的三次采油技术已在各产油国中普遍采用。对国内各大油田而言,三次采油普遍采用三元复合驱技术,而其中所使用的表面活性剂严重依赖进口,在很大程度生提高了采油成本,因而实现表面活性剂的国产工业化,已经成为石油化工领域的热点问题。针对这一情况,首先合成了一种甜菜碱型两性离子表面活性剂,并对其界面张力以及乳化性能进行了测定。通过研究认为,在表面活性剂的浓度大于0.05%时,与胜利油田高温矿化度油藏原油相混合,其界面张力能够达到10-3 m N/m以下,且乳化性能良好,有较好的工业推广价值。     

论表面活性剂工业及其发展

在分析辽宁省表面活性剂工业的优势与差距的基础上,提出发展该产业的建议。     

Complexation of Surfactant/β‐Cyclodextrin to Inhibit Surfactant Adsorption onto Sand,Kaolin, and Shale for Applications in Enhanced Oil Recovery Processes. Part I: Static Adsorption Analysis

Surfactant adsorption onto solid surfaces is a major issue during surfactant flooding in enhanced oil recovery applications; it decreases the effectiveness of the chemical injection making the process uneconomical. Therefore, it was hypothesized that the adsorption of surfactant onto solid surfaces could be inhibited using a surfactant delivery system based on the complexation between the hydrophobic tail of anionic surfactants and β‐cyclodextrin (β‐CD). Proton nuclear magnetic resonance spectroscopy was used to confirm the complexation of sodium dodecyl sulfate (SDS)/β‐CD. Surface tension analysis was used to establish the stoichiometry of the complexation and the binding constant (K_a). Static adsorption testing was applied to determine the adsorption of surfactant onto different solids (sandstone, shale, and kaolinite). The release of the surfactant from the β‐CD cavity was qualitatively evaluated through bottle testing. The formation of the inclusion complex SDS/β‐CD with a 1:1 stoichiometry was confirmed. The K_a of the complexations increases as salinity and hardness concentration increases. The encapsulation of the surfactant into the β‐CD cavity decreases the adsorption of surfactant onto solid surfaces up to 79 %. Qualitative observations indicate that in the presence of solid adsorbents partially saturated with crude oil, the β‐CD cavity releases surfactant molecules, which migrate towards the oil–water interface.     

Viscoelastic properties of latex paint films in tension: Influence of the inorganic phase and surfactants

The tensile properties of latex coatings were investigated with a set of custom formulated artist-type paints at an age of 1 year. All films in the study contained a poly(methyl methacrylate-cobutyl acrylate) binder exhibiting a glass-transition at approximately 10 °C. The viscoelastic behaviour of the latex matrix is first highlighted through a series of experiments involving different strain histories and temperatures. Influence of the inorganic particle concentration and geometry is then illustrated using TiO₂ and calcined kaolin for the secondary phase. Experimental data from a wide range of conditions are summarised through master curves of secant modulus and failure strains using time–temperature superposition. The results indicate that the latex films behave in a rheologically simple manner and it is possible to predict the response outside of the experimental time-scale. An analysis by similar methods is also given for TiO₂ pigmented films with/without surfactant removed by immersion in water. Differential scanning calorimetry and atomic force microscopy were also used in conjunction with mechanical tests. The combined findings suggest that a fraction of surfactant migrates to the TiO₂ interface during film formation, where it interferes with adhesion of the acrylic matrix.     

Complexation of Surfactant/β‐Cyclodextrin to Inhibit Surfactant Adsorption onto Sand,Kaolin, and Shale for Applications in Enhanced Oil Recovery Processes. Part III: Oil Displacement Evaluation

This proof of concept research evaluates the performance of a surfactant/β‐cyclodextrin (β‐CD) inclusion complex during chemical flooding for enhanced oil recovery. It was hypothesized that the encapsulated surfactant propagates well through the porous media. Sodium dodecyl sulfate (SDS) was used to study the surfactant/β‐CD complexations. Phase behavior analysis was carried out to prepare the most favorable chemical slug formulation. A series of core flooding tests were conducted to determine the efficiency of the SDS/β‐CD inclusion complex in displacing residual oil. Surfactant flooding was conducted as tertiary oil recovery mode (after mature water flooding) by injecting 0.3 pore volume (PV) of the optimum surfactant slug that was chased by 0.3 PV of a polymer slug; followed by continuous water flooding until oil production stopped. The experimental results indicate that the encapsulated surfactant propagates well through the sandpack system and consistently produces higher incremental oil recoveries that range from 40 to 82 % over the incremental oil recovery achieved by conventional surfactant flooding.     

Surfactant concentration and morphology at the surfaces of acrylic latex films

The final outcome of surfactants during latex film formation is a topic of ongoing concern and interest. In this study of an acrylic latex containing an anionic surfactant, two notable phenomena are observed. (1) A higher surfactant concentration is present at the air surface of the latex films, regardless of the film-forming temperature and time. In some cases, surfactant is not visible in an atomic force microscope (AFM) image as a separate phase, but compositional profiles obtained with Rutherford backscattering spectrometry (RBS) reveal an enhanced concentration of surfactant over a depth from the surface that is comparable to the latex particle diameter. (2) The surfactant features that are imaged with the AFM evolve from a thin uniform layer, to a ‘finger-like' morphology, to small flat droplets, and finally to larger, hemispherical ‘blobs.' We suggest that surfactant is first deposited from the air/water interface onto the latex surface during the drying process. During this progression in the morphology of the surfactant, the ratio of the surface area-to-volume decreases. We speculate that this phenomenon is driven by a reduction in surface energy.     

Constructing Surfactant Systems with the Characteristics of Gemini and Oligomeric Surfactants Through Noncovalent Interaction

The superior physicochemical properties of gemini and oligomeric surfactants look promising in a variety of different applications. However, tedious covalent synthesis and complicated purification limit the development of these novel surfactants. Recently, it has been demonstrated as feasible to use noncovalent interactions to construct surfactant systems with the characteristics of gemini or oligomeric surfactants. This short review discusses the strategies of constructing gemini-like or oligomeric-like surfactants through noncovalent interactions by choosing proper building blocks, single-chain surfactants and gemini surfactants along with connecting molecules containing double or multiple binding sites. The current progress in this field has been summarized. This very simple and efficient way to obtain gemini and oligomeric surfactants may make a practical impact on the surfactant industry.     

表面活性剂对材料微结构与光催化性能的调控

为探讨不同性质表面活性剂对材料结构的影响,以4种常用的表面活性剂为模板,在相同的条件下制备出性能各异的铝掺杂二氧化钛（Al-TiO2）粉体材料。并对材料的微结构和组成进行了表征与分析。结果表明,表面活性剂疏水基团所含碳原子数与Al-TiO2粉体的微晶尺寸呈负相关性,与晶格应力呈正相关性。表面活性剂诱导Al3 进入TiO2晶格的质量分数越大,晶格应力越大。Al-TiO2粉体材料的可见光降解吡啶的性能主要是由表面活性剂本身特定的分子结构及其所导致的氧空位浓度大小来决定,而不是能带间隙的宽窄来决定。阴离子表面活性剂对材料的微结构有很大的调控作用,其中SDS为最大;阳离子表面活性剂CTAB次之,两性表面活性剂对材料性能的调控没有优异表现。     

Over‐expression of glycerol dehydrogenase and 1,3‐propanediol oxidoreductase in Klebsiella pneumoniae and their effects on conversion of glycerol into 1,3‐propanediol in resting cell system

BACKGROUND: Glycerol dehydrogenase [EC.1.1.1.6] and 1,3‐propanediol oxidoreductase [EC.1.1.1.202] were proved to be two of the key enzymes for glycerol conversion to 1,3‐propanediol in Klebsiella pneumoniae under anaerobic conditions. For insight into their significance on 1,3‐propanediol production under micro‐aerobic conditions, these two enzymes were over‐expressed in K. pneumoniae individually, and their effects on conversion of glycerol into 1,3‐propanediol in a resting cell system under micro‐aerobic conditions were investigated. RESULTS: In the resting cell system, over‐expression of 1,3‐propanediol oxidoreductase led to faster glycerol conversion and 1,3‐propanediol production. After a 12 h conversion process, it improved the yield of 1,3‐propanediol by 20.4% (222.1 mmol L⁻¹ versus 184.4 mmol L⁻¹) and enhanced the conversion ratio of glycerol into 1,3‐propanediol from 50.8% to 59.8% (mol mol⁻¹). Over‐expression of glycerol dehydrogenase in K. pneumoniae had no significant influence both on 1,3‐propanediol yield and on the conversion ratio of glycerol into 1,3‐propanediol in the resting cell system. CONCLUSION: The results were important for an understanding of the significance of glycerol dehydrogenase and 1,3‐propanediol oxidoreductase in 1,3‐proanediol production under micro‐aerobic conditions, and for developing better strategies to improve 1,3‐propanediol yield. Copyright © 2008 Society of Chemical Industry     

Surfactant concentration effects on the microemulsion polymerization of vinyl acetate

The polymerization of vinyl acetate in oil-in-water microemulsions stabilized with cetyltrimethylammonium bromide (CTAB) is reported here as a function of surfactant concentration. Reaction rate decreases as the CTAB/water ratio is increased in the parent microemulsions. Polymer particles in the latexes grow with conversion; they also become bigger as the initial surfactant content is increased. Number-average molar masses are smaller than those expected by termination by chain transfer to monomer, but weight-average molar masses increased as the surfactant concentration in the parent microemulsion is raised. However, the latter are much smaller than those obtained by polymerization in an emulsion stabilized with the same surfactant. Possible explanations to this unusual behavior are provided here.     

A Systematic Study of Mixed Surfactant Solutions of a Cationic Ester-Bonded Dimeric Surfactant with Cationic, Anionic and Nonionic Monomeric Surfactants in Aqueous Media

A novel cationic biodegradable dimeric (gemini) surfactant, ethane-1,2-diyl bis(N,N-dimethyl-N-hexadecylammoniumacetoxy) dichloride (16-E2-16), containing an ester-linked spacer was synthesized. Its pure and mixed micellization properties with monomeric surfactants cetyl trimethyl ammonium chloride, cetyl pyridinium chloride, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, cetyl alcohol ethoxylate (20EO) and tert-octylphenol ethoxylate (9.5EO) were investigated by surface tension measurements at 30 °C. The critical micelle concentration (CMC) of 16-E2-16 is well below that of cetyl trimethyl ammonium chloride containing the same number of carbon atoms in the hydrophobic tail per polar head. At different mole fractions of the gemini surfactant, the CMCs of the gemini-conventional binary mixtures were determined and were found to be less than the ideal CMC values in all the cases indicating synergistic interactions. Aggregation number and Stern–Volmer constant, obtained by the fluorescence quenching technique, also support the synergistic behavior of the surfactant systems.