石油磺酸盐结构与界面活性关系研究

对25个不同来源及批次的石油磺酸盐样品进行界面张力测试、质谱分析,研究了其结构与界面活性之间的相互关系.实验结果表明:高碳链C17~C25磺酸盐含量的高低对界面活性具有最主要的影响,含量较高则界面活性较优.另外当样品所含组分的分子量在200~800范围内均匀分布时,相对丰度最大的分子离子峰聚集在479(C23苯磺酸盐)附近的样品界面活性则较优.     

重烷基苯磺酸盐的界面性质和驱油机理

重烷基苯磺酸盐是在三次采油中广泛采用的表面活性剂之一，但重烷基苯原料组成复杂导致最终磺化产物的驱油效果差异很大.实验通过柱层析的方法将重烷基苯分离成6个族组分，并对其中的二烷基苯、单烷基苯和二烷基茚萘满、烷基萘、多苯烷进行磺化，中和提纯后对各磺酸盐进行界面张力测定.通过对比不同矿化度下界面张力以及各组分复配后的界面张力，对原油等效烷烃数(EACN)以及各组分碳数最低值(nmin)测定，得出各组分之间协同效应的规律和复配机理，从而阐明了重烷基苯磺酸盐的驱油机理.通过研究十二烷基苯磺酸钠(LAS)与各组分之间的复配作用对上述规律和机理进行了进一步验证.     

阴阳离子表面活性剂体系超低油水界面张力的应用

通过阴阳离子表面活性剂复配,在实际油水体系中获得了超低界面张力.通过在阴离子表面活性剂分子结构中加入乙氧基(EO)链段,以及采用阴阳离子加非离子型表面活性剂的三组分策略,有效解决了混合表面活性剂在水溶液中溶解度问题.进而研究了阳离子表面活性剂结构、非离子表面活性剂结构、三者组分配比、表面活性剂总浓度等因素对油水界面张力的影响,从而在胜利油田多个实际油水体系中获得了较大比例范围和较低浓度区域的油水超低界面张力,部分体系甚至达到了10-4 mN·m-1.由于阴阳离子表面活性剂间强烈的静电吸引作用,相关体系具有很好的抗吸附能力.经过石英砂48 h吸附后,体系仍然具有很好的超低界面张力.     

油、水和混合表面活性剂"混相体系"的超低界面张力

本文考察了几种表面活性剂的复配体系,结果表明：油水两相极易混合（“混相”）的体系,界面张力必定超低。进而又了盐浓度及温度对体系界面张力的影响,油一水界面张力超低时,体系存在特殊的液晶结构,利用形成超低界面张力和混相体系的分散及稳定,从实验结果看,液晶更可能分散于体相中。含非离子的复配体系,存在相反转温度（ＰＩＴ）,且在相反转温度时界面张力出现最低值。     

系列烷基苯磺酸盐对烷烃的动态界面张力研究

从表面活性剂分子量、表面活性剂浓度、电解质浓度、烷烃碳数等方面考察了系列烷基苯磺酸盐异构体纯化合物的油水动态界面张力行为.研究表明,表面活性剂分子量增大和电解质浓度增加使界面张力动态变化减慢,达到平衡所需时间延长;表面活性剂浓度增加和烷烃碳数增加使界面张力动态变化加快,达到平衡所需时间减少.     

不同体系中油酸甲酯与烷基苯磺酸盐协同效应研究

研究了表面活性剂/盐/模拟油体系与表面活性剂/碱/模拟油体系中油酸甲酯与表面活性剂协同效应机理.结果表明两种体系中协同效应机理不同.在盐体系中,油酸甲酯主要通过改变油相的等效烷烃碳数(EACN) 影响表面活性剂在油水相分配.而碱体系中,油酸甲酯影响表面活性剂在油水相分配从而影响界面张力；另一方面,油酸甲酯吸附在界面上顶替表面活性剂分子影响界面张力.对于不同结构表面活性剂,两种作用竞争的结果不同.     

餐厨废油制备的生物基两性表面活性剂的油水界面性能

以餐厨废油制备了生物基两性表面活性剂,应用界面张力和动态光散射方法,研究了该生物基两性表面活性剂体系的油水界面性能及在溶液中的聚集行为。 在无外加碱条件下,由餐厨废油制备的表面活性剂表现出良好的界面性能,在50~70 ℃以及pH值为7~12的条件下,均可以将油水界面张力降至超低值(<10^-3 mN/m),在不同的油藏模拟地层水中均保持较好的界面活性;分别在50、-20和4 ℃下保存,其界面活性均未受到明显影响。 在水溶液中形成的聚集体的平均流体力学半径为10~30 nm,无机盐离子的加入可使聚集体的粒径上升。 基于其优良的界面性质和可再生来源,由餐厨废油制备的生物基两性表面活性剂在三次采油方面具有重要的应用价值。     

ASP复合驱油体系瞬时界面张力的研究

以胜利油田孤岛试验区原油为油相,用正交试验筛选了碱/天然混合羧酸盐/聚合物驱油体系,讨论了各组分对ASP复合驱油体系油水瞬时界面张力的影响,并探讨了各组分间的相互作用机理及其在油水界面的吸附机理。     

羟基取代的烷基苯磺酸盐在水/气和水/癸烷界面的结构特点（摘要）

驱油表面活性剂的分子设计是一项重要的研究课题.设计新型高效的驱油表面活性剂关键的问题在于如何洞察表面活性剂的结构和功能的关系.长线性烷基苯磺酸盐是一类非常流行的表面活性剂,广泛应用于工业和日常生活中.关于烷基苯磺酸盐的结构和功能研究已有大量的实验和理论工作报道.近来,结合分子设计的思想,实验上合成了新型的羟基取代的烷基苯磺酸盐表面活性剂,并研究了这类新型表面活性剂动态的界面行为.我们从理论上利用分子动力学模拟的方法研究了羟基取代的烷基苯磺酸盐单分子层在水/气和水/癸烷界面的结构特点.从液体密度剖面图、氢键、表面活性剂聚集结构和有序参数等方面,详细报道了2-羟基-3-癸基-5-辛基苯磺酸钠这种新型阴离子表面活性剂的界面特征.模拟结果表明随着表面活性剂分子数目的增加,每个表面活性剂在单分子层上形成分子内氢键的平均数目将下降,但形成分子内氢键的结构仍处于主导地位;烷基尾链的疏水部分,尤其是苯环3号位上取代的癸基随着表面活性剂覆盖度增大,向界面外延伸并且更加有序;二维径向分布函数描绘了表面活性剂聚集结构的特点并暗示了癸烷相将影响表面活性剂疏水部分的取向;表面活性剂分子容易形成长程氢键结构.我们的模拟结果是对实验研究的一个重要补充.此外,模拟中我们利用gromacs和ffamber程序,使用了全原子模型,这将为模拟烷基苯磺酸盐表面活性剂的界面行为提供新的方案.     

系列烷基苯磺酸盐对烷烃的动态界面性能研究

从表面活性剂分子量、表面活性剂浓度、电解质浓度、 烷烃碳数等方面考察了系列烷基苯磺酸盐异构体纯化合物的油水动态界面张力行为。研究表明,表面活性剂分子量越大和电解质浓度增加使界面张力动态变化越慢,达到平衡所需时间越长;表面活性剂浓度增加和烷烃碳数增加使界面张力动态变化加快,达到平衡所需时间减少。     

Surfactants Synthesis Using Petroleum Fractions and Crude Oil: Application in Microemulsion Formulation

Surfactant synthesis was realized from Algerian crude oil and petroleum fractions. To predict the composition (wt%) in paraffins, naphtenes, and aromatics, the crude oil and petroleum fractions were first characterized using the n-d-PA empirical method of Robert. The characterization showed a good level in aromatics compounds which give high yield in the sulfonation reaction by oleum. The synthesized surfactants were characterized by spectroscopic techniques (UV, FTIR) and by critical micelle concentration (CMC), Krafft temperature, solubility (in aqueous and in salt solution), molecular weight, and matter actives (%) measurements. The formulation of microemulsion using synthesized surfactant from plat format petroleum fraction showed a Winsor III type system. The effect of salinity demonstrates the existence of an optimal value of NaCl concentration for which the interfacial tension takes the lowered value (10^?4 mN/m). Viscosity measurements confirm that the formulated microemulsion has a Newtonian behavior.     

Aqueous surfactant solutions which exhibit ultra-low tensions at the oil-water interface

Ultra-low values of the tension at an oil-aqueous electrolyte solution interface can be developed by the addition of water-soluble surfactants of the petroleum sulfonate type. Interfacial tensions in the range of 10⁻³ dyne/cm or lower are readily achieved with surfactant concentrations of the order of 0.1 wt%. For a given oil and aqueous solution, the minimum interfacial tension resulting from the addition of a petroleum sulfonate depends markedly on the average equivalent weight of the sulfonate. Sulfonates having average equivalent weights higher and lower than a previously determined optimum weight, when mixed so as to yield this particular average weight, will also produce ultra-low interfacial tensions. For a given oil, additional control of this unusual type of interfacial activity is accomplished by adjustment of the electrolyte concentration of the aqueous phase.     

电喷雾质谱法分析三次采油用石油磺酸盐

采用电喷雾质谱法测定了胜利油田三次采油用石油磺酸盐样品的分子量分布范围在200～600,数均分子量为488,重均分子量为534.鉴别出烷基苯磺酸盐、烷基萘磺酸盐、烷基茚满磺酸盐等为胜利油田磺酸盐的主要组分.同时对来自胜利、大庆、克拉玛依和玉门4个不同油田的石油磺酸盐进行区别分析.     

石油磺酸盐体系中相微乳液研究

宽分子量分布的石油磺酸盐在低浓度时有正丁醇、正构烷烃、盐存在的情况下能成中相微乳液。研究了盐浓度、烷烃种类、醇浓度对该体系中相微乳液的形成及特性影响,得到中相微乳液的特性参数;最佳含盐量Ｓ＾＊、增溶参数σ、盐宽△Ｓ、界面张力γ等,并从理论上进行了探讨。采用模拟驱油装置测定了体系的驱油效率,对优化驱油体系设计具有重要意义。     

Adsorption kinetics of asphaltenes at the oil-water interface and nanoaggregation in the bulk

Asphaltenes constitute high molecular weight constituents of crude oils that are insoluble in n-heptane and soluble in toluene. They contribute to the stabilization of the water-in-oil emulsions formed during crude oil recovery and hinder drop-drop coalescence. As a result, asphaltenes unfavorably impact water-oil separation processes and consequently oil production rates. In view of this there is a need to better understand the physicochemical effects of asphaltenes at water-oil interfaces. This study elucidates aspects of these effects based on new data on the interfacial tension in such systems from pendant drop experiments, supported by results from nuclear magnetic resonance (NMR) and dynamic light scattering (DLS) studies. The pendant drop experiments using different asphaltene concentrations (mass fractions) and solvent viscosities indicate that the interfacial tension reduction kinetics at short times are controlled by bulk diffusion of the fraction of asphaltenes present as monomer. At low mass fractions much of the asphaltenes appear to be present as monomers, but at mass fractions greater than about 80 ppm they appear to aggregate into larger structures, a finding consistent with the NMR and DLS results. At longer times interfacial tension reduction kinetics are slower and no longer diffusion controlled. To investigate the controlling mechanisms at this later stage the pendant drop experiment was made to function in a fashion similar to a Langmuir trough with interfacial tension being measured during expansion of a droplet aged in various conditions. The interfacial tension was observed to depend on surface coverage and not on time. All observations indicate the later stage transition is to an adsorption barrier-controlled regime rather than to a conformational relaxation regime.     

阴离子表面活性剂在水/正烷烃界面的分子动力学模拟(英文)

利用分子动力学模拟方法研究了阴离子表面活性剂在水/正烷烃(壬烷,癸烷和十一碳烷)界面的结构和动力学特点.十六烷基苯磺酸钠作为研究对象,其中苯磺酸基团在十六碳烷的第4号碳原子上,记作4-C16.分析了不同油相和特定盐度条件下正烷烃-表面活性剂-水体系的界面特点(如密度剖面图、界面张力和径向分布函数).模拟结果表明平衡模型体系展现了一个很好的水/正烷烃界面.当加氯化钠到水溶液中,正烷烃-表面活性剂-水体系的界面张力有微小的变化,有趣的是表面活性剂二面角的反式结构分数的变化联系着界面张力的微小变化.可见,表面活性剂在界面处的结构对降低界面张力起到重要的作用.此外,还发现表面活性剂的极性头与钠离子和水分子存在较强的相互作用.     

The array and interfacial activity of sodium dodecyl benzene sulfonate and sodium oleate at the oil/water interface

There is a close correlation between the interfacial activity and the adsorption of the surfactant at the interface, but the detailed molecular standard information was scarce. The interfacial activity of two traditional anionic surfactants sodium dodecyl benzene sulfonate (SDBS) and sodium oleate (OAS) were studied by experimental and computer simulation methods. With the spinning drop method and the suspension drop method, the interfacial tension of oil/aqueous surfactant systems was measured, and the influence of surfactant concentration and salinity on the interfacial tension was investigated. The dissipative particle dynamics (DPD) method was used to simulate the adsorption of SDBS and OAS at the oil/water interface. It was shown that it is beneficial to decrease interfacial tension if the hydrophobic chains of the surfactant and the oil have similar structure. The accession of inorganic salts causes surfactant molecules to form more compact and ordered arrangements and helps to decrease the interfacial tension. There is an osculation relation between interfacial density and interfacial activity. The interfacial density calculated by molecular simulation is an effective parameter to exhibit the interfacial activity.     

支状嵌段聚醚的界面聚集行为及对原油乳状液的破乳作用

合成了三种不同聚氧丙烯/聚氧乙烯(PPO/PEO)比例的含苯环支状嵌段聚醚, 通过界面张力、界面流变、表面压以及对原油乳状液的破乳脱水效果的测定, 考察了其界面聚集行为和破乳作用对PEO含量和分子量的依赖性, 并且对比研究了三种支状聚醚分子交联前后的破乳性能. 结果表明, PEO含量高且分子量大者,其单分子界面占据面积大, 在油/水界面达到吸附平衡的时间短, 其油/水界面扩张模量及扩张弹性均高于PEO含量较少者. 但是对原油乳状液的破乳脱水效果则是PEO含量居中的聚醚最好. 温度影响和交联与否的研究表明, 交联并不能提高分子量较大的聚醚对原油乳状液的破乳效果, 温度对聚醚分子交联前后的破乳效果有不同的影响规律. 本研究可为原油集输过程中化学品的选择与应用提供一定的依据.     

Studies of Synergism/Antagonism in Sodium Alkyl Benzene Sulfonate/Methyl Oleate Model Oil Systems

Experimental studies are conducted in order to elucidate the mechanisms responsible for synergism/antagonism for lowering interfacial tension in alkyl benzene sulfonate/brine/methyl oleate model oil and alkyl benzene sulfonate/alkali/methyl oleate model oil systems. We found that different mechanisms exist in above two systems. In alkyl benzene sulfonate/brine/methyl oleate model oil systems, methyl oleate influences the partition of added surfactants between oil and aqueous phase by changing equivalent alkane carbon number (EACN) value of model oil. In alkyl benzene sulfonate/alkali/methyl oleate model oil systems, methyl oleate in oil phase has two functions: on the one hand, it influences the partition of surfactant between oil and aqueous phase; on the other hand, it directly affects IFT by displacing surfactant molecule or forming mixed film with surfactant molecule at the interface.