脂肪酸甲酯磺酸钠与改性木质素磺酸钠的复配及其物化性能的研究

木质素磺酸盐(LS)是制浆造纸的副产物,属于高分子表面活性剂。实验通过复配的方法,研究了脂肪酸甲酯磺酸钠(MES)与改性木质素磺酸钠(GLS)复配后的表面张力以及CMC的变化;同时,通过测定乳化性能、钙皂分散力以及泡沫的性能,来进一步阐明复配体系物化性能的变化规律。研究结果表明,复配体系的水溶液表现出更低的CMC以及表面张力。同时,随着复配体系中改性木质素磺酸钠比例的增加,复配体系的乳化力升高,表现出协同效果;复配体系的起泡力几乎不受改性木质素磺酸钠的影响,但消泡速度加快。     

水性硬脂酸的制备及性能

采用相反转技术,通过氨化改性自乳化和外加表面活性剂的途径对硬脂酸进行了水性化,发现采用外加表面活性剂的途径能得到稳定性更好的水性硬脂酸。研究了表面活性剂种类、用量和油水比对水性硬脂酸体系的稳定性、黏度以及平均粒径的影响。结果表明,当采用十二烷基二苯醚二磺酸钠(SDD)/平平加(PER)复合表面活性剂,且m(PER)∶m(SDD)=2、搅拌速率为11 000 r/m in时,可得到平均粒径为10~20μm的稳定的水性硬脂酸;改变复合表面活性剂的用量,可有效地控制体系的稳定性、黏度及平均粒径。硬脂酸质量分数在12%以下时,所得产品的黏度较低;超过15%后,体系黏度急剧增加。     

油水界面上阴/阳离子型复配表面活性剂体系的分子动力学模拟

采油过程中阴/阳离子型表面活性剂复配使用可显著增强驱油效果,对其微观机理的深入研究有助于驱油用表面活性剂的结构优化设计及使用。采用分子动力学方法研究了不同摩尔比的阴离子表面活性剂聚醚羧酸钠(PECNa)和阳离子表面活性剂十八烷基三甲基氯化铵(OTAC)复配体系在油水界面上的分子行为和物理性质。结果表明,复配体系比单种表面活性剂体系更有利于降低油水界面张力。不同复配比体系中,两种表面活性剂头基相反电荷间的吸引作用使表面活性剂之间对各自反离子的静电吸引作用减弱,且等摩尔比体系尤为明显。阴离子表面活性剂的亲水头基对阳离子表面活性剂亲水头基形成的水化层内水分子的结构取向无显著影响,反之亦然。通过调节两种离子型表面活性剂的复配比例,可调整油水界面吸附层微观结构,有望降低油水界面张力,提高采收率。     

改变碱型对复配表面活性剂三元体系界面张力的影响

在复配表面活性剂(重烷基苯磺酸盐与石油磺酸盐比例为1:3)条件下,用强碱、弱碱、盐、以及三者之间复配后配制三元体系进行界面活性研究,通过对复配表面活性剂的弱碱三元体系在低碱低表面活性剂浓度下的界面张力扫描,绘制界面活性图,研究复配条件下强碱、弱碱、盐对三元复合体系界面张力的影响。     

低渗透油藏阴离子/非离子表面活性剂复配机理研究

针对低渗透油藏注水开发采收率低的问题,进行了阴非复配表面活性剂的筛选与评价研究。通过对界面张力及乳化性能的测定,确定十二烷基苯基磺酸盐(SDBS)与脂肪醇聚氧乙烯醚(AEO-9)进行复配,具有良好的表面活性剂性能。通过阴非复配体系的特点、相渗曲线分析以及岩心驱替实验,发现SDBS/AEO-9阴非复配体系具有降低注入压力、提高最终采收率的能力,能够很好的应用于低渗透油藏。确定当表面活性剂浓度为0.5%时,该表面活性剂复配体系能够降低界面张力至10-3m N·m-1,可提高采收率5.41%。     

超低界面张力阴离子复合型驱油体系性能研究

采用旋转滴法分别测定了两种单一阴离子型表面活性剂体系和阴/阴离子复配型表面活性剂体系的油水界面张力,讨论了在50℃下表面活性剂的浓度、矿化度对油水界面张力的影响以及复配体系的最佳复配质量比,以此提高原油的采收率,评价了复配型体系表面活性剂的性能。结果表明,50℃、矿化度为3×104mg/L时将这两种阴离子表面活性剂以1∶1的质量比复配后,可以使油水界面张力值降至10-5m N/m,最终筛选出性能优越的超低界面张力驱油体系WY-2,同时此复配体系具有较好的稳定性和良好的乳化能力。     

超低界面张力阴离子复合型驱油体系性能研究

采用旋转滴法分别测定了两种单一阴离子型表面活性剂体系和阴/阴离子复配型表面活性剂体系的油水界面张力,讨论了在50℃下表面活性剂的浓度、矿化度对油水界面张力的影响以及复配体系的最佳复配质量比,以此提高原油的采收率,评价了复配型体系表面活性剂的性能。结果表明,50℃、矿化度为3×104mg/L时将这两种阴离子表面活性剂以1∶1的质量比复配后,可以使油水界面张力值降至10-5m N/m,最终筛选出性能优越的超低界面张力驱油体系WY-2,同时此复配体系具有较好的稳定性和良好的乳化能力。     

阴阳离子复配体系的表面活性及应用性能

研究了2种具有不同EO加合数的阴离子表面活性剂壬基酚聚氧乙烯醚丙基磺酸钠[NPSO-n(n=5,8)]与阳离子表面活性剂十二烷基二甲基苄基氯化铵(1227)复配体系的表面活性和应用性能、混合吸附层和混合胶束的组成及相互作用参数(βs和βm)。结果表明:复配体系的临界胶束浓度(cmc)较单一组分低得多,并随1227摩尔分数的增加而降低,当1227的摩尔分数达0.5时,cmc最低,比单一表面活性剂的cmc低2个数量级;并且混合胶束和混合吸附层中的分子相互作用较强,混合胶束和混合吸附层中阴阳离子表面活性剂的摩尔比接近1∶1;2种复配体系均具有比单一阴离子表面活性剂更好的泡沫、润湿和乳化性能。     

复配表面活性剂-模拟油-水体系的界面张力研究

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 m N/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C15EC-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 m N/m。     

表面活性剂三元复配技术用于稠油降黏的研究

针对辽河油田超稠油开采过程中的难降黏问题,根据乳化降黏机理,在表面活性剂单剂及阴-非离子表面活性剂二元复配降黏体系研究的基础上,探究阴离子表面活性剂十二烷基磺酸钠(SDS)和非离子型OP-10、吐温-80三元复配体系对稠油降黏率、乳化率及乳液稳定性的影响。结果表明,阴-非离子表面活性剂三元复配体系对稠油的降黏及乳化效果,比二元复配体系的降黏及乳化效果差。因此,在采油生产中,通过增加表面活性剂的种类以提高稠油降黏效果的方法并不合适,应根据稠油类型和表面活性剂降黏的实验数据,正确选择表面活性剂的复配体系。     

Entry in emulsion polymerization using a mixture of sodium polystyrene sulfonate and sodium dodecyl sulfate as the surfactant

A mixture of sodium polystyrene sulfonate (NaPSS) and anionic surfactant, sodium dodecyl sulfate (SDS), was used as the emulsifier in the emulsion polymerization of styrene at 60 °C. The latexes prepared were stable, bearing the better resistance to the addition of electrolyte, and have the larger values in particle size and the higher polymerization rates than those counterparts prepared using SDS only. The NaPSS was prepared by a series of process: a concentrated cyclohexane solution of an anionically polymerized polystyrene (PS) was sulfonated with sulfuric acid at 80 °C, and then neutralized and purified through dialysis. The data of average polymer number per particle (n_p) were found useful in investigating the surfactant content effect on the entry of radicals into particles, where the latex particle size plays an important role.     

Effect of mixing protocol on formation of fine emulsions

Emulsions are usually stabilised with a mixture of surfactants with different hydrophilicity. The initial partitioning of surfactants between the dispersed phase and continuous phase, and how these phases are brought into contact, can significantly affect the emulsification processes. Dynamic-phase behaviour maps were prepared to allow for a systematic investigation of the effects of emulsification routes on emulsion properties. Six semibatch modes of additions with constant surfactant concentration across the routes were selected. For a target cyclohexane-in-water emulsion using a pair of polyoxyethylene nonylphenyl ether surfactants with a specified HLB and water volume fraction, fine droplets could form only if water dissolving the water-soluble surfactant was added to the oil dissolving the oil-soluble surfactant. This route allowed the transitional inversion to occur and as a result fine droplets were formed due to an ultra-low interfacial tension. The addition of water dissolving the water-soluble surfactant to oil dissolving the oil-soluble surfactant, direct emulsification method, produced by far large droplets because of a rather high interfacial tension. In a series of experiment, the semibatch direct and phase-inversion emulsification method, were assimilated in situ. The impeller location was used as a variable that controls which phase is added as the dispersed phase. The location of impeller in relation to the interface did not affect the emulsion drop size at a high agitation rate, but it did at a low agitation rate. Under low agitation speed and when the impeller was placed in the oil phase, the oil layer progressively, but slowly, dragged the water phase and eventually inverted to an oil-in-water emulsion, indicating that transitional-phase inversion has locally occurred in the oil layer. At a high agitation speed the mechanical energy provided by the impeller homogenised the emulsion instantaneously and did not allow the optimum formulation and the associated ultra-low interfacial tension to be reached regardless of location of the impeller. A high impeller speed increased drop size by transforming the transition inversion mechanism to a catastrophic mechanism under which the size of drops is mainly determined by the mechanical energy provided. This paper aims to show how some of the complexities involved in emulsification processes can be explained by consulting with dynamic-phase maps.     

Polystyrene ionomer aqueous dispersion. I. Process and mechanism of the phase inversion of emulsification

Aqueous dispersions of lightly sulfonated polystyrene (SPS) that was neutralized by ammonia liquor were prepared. The variations of the conductivity and viscosity of SPS ionomer solution during the emulsification process and the effect of ionic contents on the phase inversion in the emulsification process were studied. The turning points in conductivity curve and the maximum viscosity were considered as the characters of phase inversion in the process of emulsification. The mechanism of phase inversion was inferred. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1671–1675, 1998     

Production of colloidally stable latices from low molecular weight ethylene–propylene–diene copolymers

The best impact modifiers for coatings and engineering plastics include fixed morphology core-shell particles. For the present work, ethylene–propylene copolymers (EPM) and ethylene–propylene–diene copolymers (EPDM) were chosen, for their good resistance to stringent conditions, like UV-irradiation or high temperatures, to prepare the core of the desired particles.

The solution-emulsification technique was used to produce artificial latices based on low molecular weight EPM and EPDM materials. Conventional emulsification techniques as well as ‘miniemulsification’ methods have been investigated. In both cases, a larger volume of polymer is reduced into smaller sub-units using the mechanical energy of comminution techniques, i.e. an Ultra-Turrax^® and a homogenizer operating at a pressure of 300 bar and with a shear rate of approximately 3.2×10⁷ s⁻¹. The difference between conventional emulsification and miniemulsification resides in the stabilizing system. For the conventional emulsification method, an equimolar mixture of anionic (sodium dodecyl benzene sulfonate, SDBS) and nonionic (polyoxyethylene (100) stearyl ether, Brij 700) surfactants was found to be the optimal surfactant system. For the miniemulsification method, a combination of SDBS as surfactant and hexadecane or cetyl alcohol as costabilizer was the most suitable system. Both conventional emulsification and miniemulsification lead to latices with monomodal particle size distributions and volume-average diameters ranging from 300 to 400 nm, determined with light scattering techniques. The low molecular weight elastomers, exhibiting viscosities lower than 1 Pa s at 20 °C, were easily emulsified without addition of organic solvent.     

无机盐对乳状液稳定性和转相的影响

在进行化学驱油尤其是表面活性剂驱油的过程中,油藏地层水中含有的无机盐离子会对表面活性剂的乳化等性能产生影响。使用0.4%（质量分数）的十二烷基苯磺酸钠（SDBS）作为乳化剂与原油制备了水包油型乳状液,通过向SDBS溶液中加入不同浓度的共13种无机盐,考察了这些无机盐对水包油型乳状液稳定性和转相的影响。实验结果表明：钠盐和钾盐均存在最佳盐质量浓度,在此质量浓度下乳状液稳定性增强,没有引发乳状液转相;二价和三价无机盐不利于乳状液的稳定,其引发乳状液发生转相的能力依次为氧化铝＞氯化铁＞氯化钡＞氯化锶＞氯化钙＞氯化镁;处于最佳盐质量浓度时,弱碱性钠盐可与SDBS产生协同效应,有利于乳状液的稳定。     

Surfactant effect on production of monodispersed microspheres by microchannel emulsification method

Super-monodispersed oil-in-water (O/W) microspheres (MS) were produced using a microchannel (MC) emulsification technique. To investigate the effect of the surfactant on the behavior of the O/W-MS formation, the MS size and its distribution, various surfactants were used for the MC emulsification process. An MC plate with 8.9 μm equivalent diameter was employed. It was found that the super-monodispersed O/W-MS production depends on the type of surfactant used. When nonionic and anionic surfactants were used, supermonodispersed O/W-MS were produced, and the average droplet diameter was about 30 μm with a standard deviation less than 1 μm. For cationic surfactants, the super-monodispersed O/W-MS production was not successful, especially for the case where hydrophobic surfactant was dissolved in the oil phase. The results indicated that it is very important to maintain the hydrophilicity of the MC surface during the MC emulsification process. It is considered that the hydrophilic group of the anionic and nonionic surfactant was repulsed from the negatively charged MC surface so that the hydrophilicity of the MC surface was maintained. Otherwise, adsorption of the positively charged group of the cationic surfactant occurred on the MC surface which improved wetting of the MC surface and deteriorated the MC emulsification process. The analysis was supported by contact angle measurement.     

Preparation and characterization of monoclinic sulfur nanoparticles by water-in-oil microemulsions technique

Nanosized monoclinic sulfur particles have been successfully prepared via the chemical reaction between sodium polysulfide and hydrochloric acid in a reverse microemulsions system, with theolin, butanol, and a mixture of Span80 and Tween80 (weight ratio 8 : 1) as the oil phase, co-surfactant and surfactant, respectively. Transparent microemulsions were obtained by mixing the oil phase, surfactant, co-surfactant, and the aqueous phase in appropriate proportion using an emulsification machine at the room temperature. The resulting sulfur nanoparticles were characterized by dynamic light scattering (DLS), X-ray diffraction (XRD), infrared spectroscopy (IR) and transmission electron microscopy (TEM).     

系列烷基糖苷硫酸酯盐的性能研究

对实验室自制的系列烷基糖苷硫酸酯盐（APGS）表面活性剂的表面性能和应用性能进行了测定，并对其构效关系进行了研究。结果表明，系列烷基糖苷硫酸酯盐是烷基糖苷的衍生物，是一类性能优良的阴离子表面活性剂，具有优异的泡沫、润湿能力，良好的乳化、分散能力，还具有良好的抗硬水能力，具有广泛的开发应用前景。     

Microemulsion phase behavior of anionic-cationic surfactant mixtures: Effect of tail branching

This research evaluated middle-phase microemulsion formation by varying the mole ratio of anionic and cationic surfactants in mixtures with four different oils (trichloroethylene, n-hexane, limonene, and n-hexadecane). Mixtures of a double-tailed anionic surfactant (sodium dihexyl sulfosuccinate, SDHS) and an unbalanced-tail (i.e., doubletailed with tails of different length) cationic surfactant (benzethonium chloride, BCl) were able to form microemulsions without alcohol addition. The amount of NaCl required to form the middle-phase microemulsion decreased dramatically as an equimolar anionic-cationic surfactant mixture was approached. Although the mixture of anionic and cationic surfactants demonstrated a higher critical microemulsion concentration (cμc) compared to the anionic surfactant alone, the Winsor Type IV single-phase microemulsion started at lower surfactant concentrations for the anionic-cationic mixture than for the anionic surfactant alone. Under optimum middlephase microemulsion conditions, mixed anionic-cationic surfactant systems solubilized more oil than the anionic surfactant alone. Pretreatment detergency studies were conducted to test the capacity of these mixed surfactant systems to remove oil form fabrics. It was found that anionic-rich mixed surfactant formulations yielded the largest oil removal, followed by cationic-rich systems.     

Use of surfactants and blends to remove DDT from contaminated soils

Removal of dichloro‐diphenyl‐trichloroethane (DDT) from soils using surfactant‐enhanced solubilisation was studied both in batch and continuous flow arrangements to determine if there were advantages to using a combination of non‐ionic (Tween and Brij) and anionic surfactants. It was observed that the presence of the anionic surfactant sodium dodecyl benzene sulphonate improved the DDT removal efficiency, but had a potentially negative effect on flow rates in column leaching experiments at concentrations over 0.1%. The potential for re‐use of the surfactant mixture was studied and demonstrated by removing DDT and its metabolites from the surfactant solution using activated carbon. © 2011 Canadian Society for Chemical Engineering