连接基对双子表面活性剂2C_(12)H_(25)C_nAm表/界面性质的影响

通过三步反应合成出一系列不同碳原子数连接基阴离子双子表面活性剂(N,N′-双十二烷基-双羧丙酰基-烷撑二胺(2C12H25CnAm,n=2,3,4)。三种表面活性剂都具有低临界胶束浓度,且都能高效地降低表面张力。通过pC20,CMC/C20,pC30,CMC/C30参数分析了它们的吸附和胶束化行为。表面活性剂CMC值随连接基长度的增加先减小再增大,在n=3时达到最小2.17×10-5 mol/L;界面张力值随着连接基长度的增加而减小,最小可达到1.87mN/m。     

The effect of cationic surfactant additives on flow properties of crude oil

Pretreatment of the crude oil with flow improver or pour point depressants has received the greatest acceptance due to its simplicity and economy. Three cationic surfactants Bola form based on urea were prepared by quaternization reaction with alkyl dihalides of different chain length (hexayl, decyl-, and dodecyl-dibromide). The prepared compounds (U6, U10, and U12) were evaluated as surface active agents as well as pour point depressant for crude oil compared to monosurfactant (U12a) corresponding to (U12). The surface parameters of each synthesized surfactant were calculated from their surface tension profile including the critical micelle concentration, maximum surface excess (Γ_max), and the minimum surface area (A_min). The free energies of micellization (ΔG°_mic) and adsorption (ΔG°_ads) were also calculated. Its pour point and viscosity decreased significantly after adding surfactants. FTIR studies of crude-surfactant mixture showed remarkable decrease in concentration of viscosity enhancing groups such as alkanes, alcoholic, and acidic groups, indicating the effectiveness of both the surfactants.     

Synthesis and evaluation of some derivatives of polysiloxanes

Silicone surfactants have been widely used in our daily life and many industrial fields on the basis of their unusual properties. Only in the past decades has the use of silicone as a hydrophobic building block for the preparation of surfactants become common. The recent trend to combine silicone, polyoxyalkylene and carbohydrate moieties in the same molecule has resulted in a plethora of new compounds with new properties.In this article, we report the preparation of a series of “glycopolysiloxanes” surfactants with different molecular weights. They were structurally characterized by IR, ¹H NMR and MS.Specifically, the critical micelle concentration (cmc), effectiveness of surface tension reduction (π_cmc), maximum surface excess (Γ_max), minimum surface area (A_min) and standard free energies of micellization (ΔG°_mic) and adsorption (ΔG°_ads) have been determined from aqueous surface tension measurements using Du-Nouy Tensiometer (KRUSS K6 type 4851) with a platinum ring. All the surfactants have good surface properties and have low cmc.The bacteriostatic power of these polymers was tested and compared under the same conditions in aqueous solution against common strains of Gram positive bacteria and strains of Gram negative bacteria.     

季铵盐型Gemini 表面活性剂水溶液的表面和油-水界面特性

 用 DCAT-21型表面张力及接触角仪测定了不同结构的季铵盐型 Gemini 表面活性剂 C_n-s-C_n·2Br 溶液的表面张力和界面张力变化,为选择一种较好的表面活性剂作为驱油剂提供基础。结果表明,烷基链长n 均为12时,随联接基团数s 的增加,季铵盐型 Gemini 表面活性剂降低表面和界面张力能力减小。s 相同时,随着烷基链长n 增加,Gemini 表面活性剂的临界胶束浓度（CMC）减小。加入无机盐可以进一步降低 Gemini 表面活性剂的 CMC 值。季铵盐型 Gemini 表面活性剂的 CMC 值较类似结构的单链单头普通表面活性剂的 CMC 值低,且达到最低界面张力时的浓度比单链单头普通表面活性剂低2个数量级。Gemini表面活性剂的高表面活性主要由其特殊的分子结构所决定。     

Physicochemical Properties of Aryl Oleate Surfactants in Aqueous Solution

Sodium and potassium aryl oleates, containing different aromatic rings on the straight aliphatic chain, were synthesized. Their surface properties at 25°C, surface tensions at CMC, γ_cmc, surface excess concentration, Γ_m, the area per surfactant molecule at the air/water interface at surface saturation, A_m, efficiency in surface tension reduction, pC₂₀, effectiveness in surface tension reduction, ∏_cmc, as well as standard free energies of adsorption, Δ G_ads°, and of micellization, Δ G_mic°, were determined. The CMCs and γ_cmcs of these surfactants increased with the increase of the size of aromatic ring from phenyl to a-methylnaphthyl. Introduction of aromatic rings to the alkyl chain decreased the efficiency and effectiveness in reducing water surface tension. The results indicated that the size of lipophilic group was important in effecting the interfacial surface area occupied by the surfactant molecules.     

Effect of chemical structure on the cloud point of some new non-ionic surfactants based on bisphenol in relation to their surface active properties

A series of non-ionic surfactants were prepared from bisphenol derived from acetone (A), acetophenone (AC) and cyclohexanone (CH). The prepared bisphenols were ethoxylated at different degrees of ethylene oxide (27, 35, 43). The ethoxylated bisphenols were non-esterified by fatty acids; decanoic, lauric, myristic, palmitic, stearic, oleic, linoloic and linolinic. Some surface active properties for these surfactants were measured and calculated such as, surface tension [γ], critical micelle concentration [CMC], minimum area per molecule [A_min], surface excess [C_max], free energy of micellization and adsorption [ΔG_mic] and [ΔG_ads]. At a certain temperature, the cloud point was measured for these surfactants. From the obtained data it was found that; the cloud point is very sensitive to the increase of the alkyl chain length, content of ethylene oxide and degree of unsaturation. The core of bisphenol affected the cloud point sharply and they are ranked regarding bisphenol structure as BA > BCH > BAC. By inspection of the surface active properties of these surfactants, a good relation was obtained with their cloud points. The data were discussed on the light of their chemical structures.     

The Preparation and Characterization of Some Novel Quaternary Iminium Salts Based on Schiff-base as a Corrosion Inhibitor

Abstract

Novel quaternary iminium compounds, namely, N-(4-methoxybenzylidene)-N-benzyldodecyliminium chloride (I_a), N-(4-methoxybenzylidene)-N-benzylhexadecyl iminium chloride (I_b), N-(4-methoxybenzylidene)-N-benzyloctadecyliminium chloride (I_c), and N-benzylidene-N-benzyldodecyliminium chloride, were prepared. The surface properties such as surface and interfacial tension, foaming, and emulsifying power of these surfactants were investigated. The surface parameters including critical micelle concentration (CMC), maximum surface excess (Γ_max), minimum surface area (A_min), efficiency (PC₂₀), and effectiveness (π_CMC) were calculated. Free energy of micellization (ΔG°_mic) and adsorption (ΔG°_ads) were calculated.     

阴-非离子型Gemini表面活性剂的胶束化热力学性能

采用表面张力法研究了9种阴-非离子型Gemini表面活性剂在水溶液中胶束化的热力学性质,并考察了温度与分子结构对胶束化的影响。实验结果表明,阴-非离子型Gemini表面活性剂在水溶液中胶束化是一个自发过程,主要来自熵驱动,温度升高不利于胶束化,且标准熵变对标准吉布斯自由能变的贡献有下降趋势,标准焓变对标准吉布斯自由能变的贡献有增大趋势;阴-非离子型Gemini表面活性剂在水溶液中胶束化存在焓熵补偿现象,焓熵补偿温度均在(307±2)K范围内,基本不随阴-非离子型Gemini表面活性剂的分子结构的改变而变化,随联接链增长或氧乙烯结构单元数目的增加,形成胶束的能力与稳定性均提高,随温度的升高,形成胶束的能力与稳定性均下降;临界胶束浓度的对数与联接链长度呈线性关系。     

Thermophysical interface properties of crude oil and aqueous solution containing sulfate anions: experimental and modeling approaches

Abstract

Sulfate anion is well-known for being one of the most active agents to be injected into the oil reservoirs and being capable of not only altering the interfacial properties of crude oil but also enhancing the water solution properties in oil recovery. In the current study, the effects of temperature and pressure were studied on interfacial tension (IFT) as well as the adsorption behavior of two different solutions containing sulfate anion using experimental measurements and modeling approaches. Although it was expected that IFT values of the studied systems might decrease as temperature increased due to the improvement in the molecule mobility and solubility of crude oil in water, which consequently might lead to the reduction in its free energy, the reverse trend was observed. The measured dynamic IFT values and adsorption behavior revealed that surface excess concentration of natural surfactants (Г_NS) can be considered as the most effective parameter on interpreting IFT behavior as a function of temperature.     

Anionic cocogem surfactants containing propyl-2-ol groups: Synthesis,surface properties and antibacterial activity against SRB bacteria

Cocogem surfactants are synthesized based on the neutralization reaction of higher monocarboxylic acids (octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, heptadecanoic acid, octadecanoic acid) and 2:1 mol of N,N'-bis(propyl-2-ol)ethylenediamine). Krafft temperatures of these surfactants and colloidal chemical properties of their aqueous solutions were determined by using tensiometric and conductometric measurements. Surface activity parameters of cocogem surfactants, critical micelle concentration (CMC), counter-ion binding degree (β), the surface tension reduction effectiveness (π_CMC), excess concentration of surface (Γ_max), as well as area per molecule at the interface (A_min), Gibbs free energy (ΔG_ad and ΔG_mic) values of adsorption and micellar formation processes are calculated. The size of the aggregates formed by anionic cocogem surfactants in an aqueous solution was determined by the DLS method. It was defined that cocogem surfactants have antibacterial properties against SRB, which is considered to be the most dangerous for the oil industry.     

Synthesis,Characterization, and Surface Activity of Some Schiff Base Cationic Surfactant Complexes Against Different Microorganisms

In this study, different metallocationic surfactants were prepared by reaction of N,N dimethyl ethylene diamine with benzaldehyde (Schiff base reaction) then quaternized the resulted tertiary amines with different alkyl halides such as dodecyl bromide and hexadecyl bromide to produce a series of quaternary ammonium salts. Finally, complexing the cationic surfactants with stannous chloride and cobalt chloride to give the corresponding metallocationic surfactants. Surface tension of these surfactants at four different temperatures was investigated. The surface and thermodynamic parameters were studied. FTIR spectra were done to confirm the structure of the compounds and their purity. The antimicrobial activity of the prepared complexes was determined via the inhibition zone diameter against different microorganisms also against sulfate reducing bacteria by the dilution method. The results indicate that these metallocationic surfactants have good surface properties and good biological activity on different microorganisms.     

脂肪醇聚氧乙烯醚磺酸盐系列表面活性剂的协同效应

为满足高温、高盐油藏三次采油的需求,采用自制的脂肪醇聚氧乙烯醚磺酸盐(NNA)系列作为抗温、耐盐驱油表面活性剂,考察了脂肪醇聚氧乙烯醚磺酸盐系列表面活性剂复配前后原油 矿化水体系界面张力的变化,并讨论了其协同效应,并采用静态吸附实验考察了该系列表面活性剂的吸附性能。结果表明,随着NNA表面活性剂分子中氧乙烯链节数的增加,原油 矿化水体系的油 水界面张力最低值对应的矿化度向着高矿化度方向移动,当氧乙烯链节数适中时,可以获得超低油 水界面张力。同系列表面活性剂复配可以显著改善表面活性剂体系的界面活性,具有明显的协同作用。复配表面活性剂使油 水界面张力达到平衡值的时间大大缩短,拓宽了达到超低界面张力的表面活性剂质量分数范围（003%～015%）,耐盐性能也得到提高,使用单剂时耐盐能力在100 g/L以下,复配后耐盐能力达到100 g/L以上。同系列表面活性剂在油砂上的吸附规律相同,从而降低了表面活性剂被地层色谱分离的可能。     

含烷氧基链节的硫酸盐表面活性剂的油-水界面张力及其对原油的乳化能力

 以壬基酚、十二醇、异构十三醇为主要原料，合成了7种含烷氧基链节的硫酸盐表面活性剂。测定了以含0.1%(质量分数) 硫酸盐表面活性剂的模拟盐水与桩106-15-X18普通稠油配制的油-水体系的界面张力，并测定了上述表面活性剂对桩106-15-X18普通稠油的乳化速率。结果表明，虽然这些表面活性剂具有较高的耐盐能力，但随着分子中氧丙烯链节数逐渐增加，油-水界面张力值最小时对应的最佳NaCl含量呈降低趋势。在合成含烷氧基链节的硫酸盐表面活性剂时，可以通过控制氧丙烯链节长度，调节其在油-水体系中获得的低界面张力区的特点，使之适应不同盐含量的地层。含烷氧基链节的硫酸盐表面活性剂降低油-水界面张力的能力和其对稠油的乳化速率没有简单的对应关系。     

阳离子Gemini对固体表面润湿性的影响

研究了阳离子双子表面活性剂对固体表面润湿性的影响,并从机理上进行了探讨,结果表明,与普通表面活性剂相比,阳离子双子表面活性剂在很低浓度时就能将油湿的固体表面转化为强水湿表面,并且不会改变水湿表面的润湿性;另外,对联接基长度相同但是疏水烷基链长度不同的双子表面活性剂对固体表面的润湿性影响进行了考察,结果发现疏水烷基链短的双子表面活性剂较疏水烷基链长度长的双子表面活性剂更能显著影响固体表面的润湿性。     

Preparation and evaluation of some amide ether carboxylate surfactants

A homologous series of new mild surfactants, namely: Alkyl amide ether carboxylates surfactants (AEC) RCO–NHCH₂CH₂O (CH₂CH₂O)₆CH₂COONa, were synthesized by esterification, amidation, ethoxylation and carboxymethylation reaction steps of fatty acids (Lauric, Myristic, palmitic, stearic, oleic or linoleic). The chemical structures of the prepared compounds were confirmed using different spectroscopic techniques, FTIR spectroscopy, mass spectra and HNMR. The surface properties including surface and interfacial tensions, foaming height, emulsification power, calcium ion stability, stability to hydrolysis and critical micelle concentration (cmc) were determined. The study of their surface properties showed their stability in hard water and in acidic and alkaline media. These compounds have high calcium ion stability. The low foaming power could have an application in the dyeing auxiliary industry. The lower values of the interfacial tension values indicate the ability of using these surfactants in several applications as corrosion inhibitors and biocides. The data revealed various advantages and potentials as a main surfactant as well as co- surfactants.     

氨基磺酸型两性双子表面活性剂的合成及性能

以十二胺、2-氯乙基磺酸钠为主要原料,采用二氯代的亲水性基团作为联结基,制备了新型氨基磺酸型两性双子表面活性剂DAS-3PA和DAS-8EO;用红外光谱对其结构进行了表征,并对其表面活性和油水界面张力进行了测试。结果表明,两性双子表面活性剂表现出优于传统表面活性剂的表面活性,25℃时DAS-3PA和DAS-8EO临界胶束浓度分别达到6．9×10^-5mol／L和8．0×10^-5mol／L,此时界面张力分别降至25．01mN／m和26．17mN／m;DAS两性双子表面活性剂倾向于吸附在油水界面上,并能有效地降低原油与水的界面张力;DAS两性双子表面活性剂与聚合物复配时表现出较好协同效应,此复配二元体系均能将油水界面张力降低至10^-3mN／m以下。     

改性聚三乙醇胺阳离子表面活性剂的合成及浮选性能评价

以三乙醇胺为单体,经高温脱水缩合得到聚三乙醇胺(PTEA),采用溴代烷烃改性PTEA得到系列阳离子型季铵盐表面活性剂Rn-PTEA.采用FTIR和1H NMR表征了Rn-PTEA的结构,考察了烷烃链长度、季铵化程度对表面张力的影响,评价了Rn-PTEA的浮选性能并探讨了浮选机理.实验结果表明,随着烷烃链长度的增加,Rn...     

羧甲基纤维素系列高分子表面活性剂与大庆原油的界面活性研究

研究了羧甲基纤维素系列高分子表面活性剂复配体系与大庆原油形成超低界面张力的条件,结果表明盐,醇的加入对高分子表面活性剂的界面活性影响不大;碱的加入能改善高分子表面活性剂分子在界面上的吸附,使界面张力大幅度下降,在适当配比下,高分子表面活性剂碱水溶液与原油可达到超代界面张力值（１０＾－３ｍＮ／ｍ）。     

混合烷基苯磺酸盐的制备、评价及分析

三次采油需要大量的高性价比磺酸盐类表面活性剂。以炼油厂馏分油为主要原料,AlCl3为催化剂合成混合烷基苯,再与发烟硫酸反应制备混合烷基苯磺酸盐,并评价合成样品的综合性能。结果表明,所制备的混合烷基苯磺酸盐与胜利油田Ⅰ、Ⅱ类油藏4个区块原油的界面张力达到了5×10^-3mN/m以下,对Ⅲ类油藏原油界面张力达到3×10^-2mN/m,且具有较宽的浓度窗口、较高的耐盐性能、较低的吸附性能、与聚合物较好的配伍性能,综合性能明显优于同类产品。红外光谱、质谱和碳数分布分析结果表明其组成比石油磺酸盐复杂,更接近于原油的组成。     

原油中天然表面活性剂的分离和性质研究

用乳化法分离出Ｐｒｅａｌｐｉｎｅ地区油中的天然表面活性剂,将它分散到液体石蜡中,测定了该分散液的表面张力,界面张力。考察了盐度水相ＰＨ值对界面张力的影响。另外,还以此分散液制备了一些太液,比较了它们的稳定性,了盐度和水相ＰＨ值对状液稳定性的影响。