Synthesis and Interfacial Properties of Bio-Based Zwitterionic Surfactants Derived from Different Fatty Acids in Non-Edible Vegetable Oils

Waste cooking oils and non-edible vegetable oils are abundant and renewable resources for bio-based materials which have showed great potential applications in many industries.In this study,five fatty acids commonly found in non-edible vegetable oils,including palmitic acid,stearic acid,linoleic acid,linolenic acid,ricinoleic acid,and their mixtures,were used to produce bio-based zwitterionic surfactants through a facile and high-yield chemical modification.These surfactants demonstrated excellent surface/interfacial properties with the minimum surface tensions ranging from 28.4 mN/m to 32.8 mN/m in aqueous solutions.The interfacial tensions between crude oil and surfactant solutions were remarkably reduced to lower values ranging from 0.0028 mN/m to 0.1983 mN/m without the aid of extra alkali,which particularly implied a great potential application in enhanced oil recovery.Meanwhile,these bio-based surfactants also showed good wetting properties(contact angles of~51°comparing with that of double distilled water,92.04°)and appropriate predicted biodegradability(degradation order of“weeks”for bio-based surfactants synthesized from saturated fatty acids,and“months”for those synthesized from unsaturated fatty acids).Bio-based surfactants synthesized from unsaturated fatty acids showed better interfacial properties in reducing interfacial tension between crude oil and formation water.The bio-based surfactants presented in this study are alternative substitutes for traditional petroleum-based surfactants in various surfactant application fields.

Fatty Acids in Heterocyclic Synthesis. Part XVII: Synthesis of Non Ionic Surfactants Containing Piperidine, Piperazine, Imidazole Based on Thiadiazole and Microbiological Activities Evaluation

A series of novel scaffolds Thiadiazolyl Piperidine, Thiadiazolyl Piperazine, thiadiazolidine, Thiadiazolyl thiazole and Thiadiazolyl-imidazole-Thione were synthesized from cheap, available and biologically active stearic acid. 2-amino-5-heptadecyl 1,3,4-thiadiazole reacts with chloroacetyl chloride and produced 2-choloro-N-(5-heptadecyl-1,3,4-Thiadiazole-2-yl) acetamide. Which allowed to react with Piperidine, Piperazine, urea and/or Thiourea and Potassium thiocyanate, and the latest scaffolds have been synthesized, respectively, and the structures of these compounds were established by elemental analysis, MS, IR and 1H-NMR spectral data. The antimicrobial activities of the synthesized compounds were evaluated in-vitro against strains of gram +ve, gram -ve bacteria and fungi. Nonionic surfactant were obtained by addition of different moles of propylene oxide (3,5,7 mole) to the synthesized compounds bearing an active hydrogen. Physico-chemical and surface properties as well as biodegradability of the synthesized non-ionic surfactants were evaluated.

Removal of Fulvic Acids from Aqueous Solutions via Surfactant Modified Zeolite

A surfactant modified zeolite（ SMZ）, i. e. , a zeolite modified by using hexadecyl trimethyl ammonium bromide （HDTMA） was used to remove fulvic acids（FA） from aqueous solution. The effects of the relevant parameters, such as the loading level of HDTMA, the contact time, the initial FA concentration, the pH, and the types of the metal carious and organics were examined. The results show that SMZ with an HDTMA loading-level of 120% of the external cation exchange capacity（ECEC） of zeolite exhibits the best performance. Although the removal of fulvic acids by SMZ occurs rapidly within the first 30 min of the contact time, a contact time of at least 4 h is required to attain the adsorption equilibrium. The removal capacity of FA by SMZ decreases with the increase of the initial FA concentration. The pH has an effect on the FA removal efficiency because it can influence the characteristics of the FA molecules. The removal of FA is considerably enhanced by Ca^2＋ or Mg^2＋ ions and is adversely affected by phenol or pentachlorophenol（PCP）. Under the optimum conditions, 98% of FA could be removed by SMZ. Furthermore, the desorption of FA and the regeneration of SMZ were studied. The results show that a 30% ethanol solution is sufficient for the regeneration of SMZ.

Synthesis, Optical and Surface Properties of the New Gemini Quaternary Ammonium Surfactants Containing DSD Acid-triazine Structure

Four novel gemini quaternary ammonium surfactants containing DSD acid-triazine structure were synthesized using a facile three-step synthetic route , from 4,4'-diamino-2,2'-disulfonic-stilbene (DSD acid), cyanuric chloride and dimethyl dodecylamine. The structures and optical properties of compounds (6a-d) were characterized by Fourier-Transform infrared (FT-IR) spectroscopy, UV-visible absorption spectra and fluorescence emission spectrum. The surface tension and the Critical Micelle Concentration (CMC) were evaluated. The result shows that the four compounds at lower concentrations can greatly reduce the surface tension of aqueous solutions. The spectroscopic properties of? these quaternary ammonium salts are assessed for their effectiveness and potential as fluorescent brightening agents.

A robust viscoelastic surfactant tolerating 20% HCl up to 150℃ for oil well stimulation

Viscoelastic surfactants(VES)are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well productivity.However,the ceiling temperature of commercial VES cannot exceed 120℃in practical use because of the poor thermal stability and fragile molecular structure,hindering their implementation in hightemperature oil reservoirs,i.e.,≥150℃.Here we synthesized a novel C22-tailed diamine,N-erucaminopropyl-N,N-dimethylamine(EDPA),and examined comparatively its rheological behavior,assemblies morphology and molecular stability in 20 wt%HCl with a commercial VES,erucyl dimethyl amidopropyl betaine(EDAB).The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150℃.Rheological results showed that the 2.5 wt%EDPA—20 wt%HCl solution maintains stable viscosity of 90 m Pa s at 150℃for 60 min,while that of 2.0 wt%EDAB HCl solution is just 1 m Pa s under identical conditions.1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context,but the EDAB suffered from degradation due to the hydrolysis of the amide group,accounting for the poor heat-resistance and acid-tolerance.The reaction rate of 2.5 wt%EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt%HCl solution at 150℃,underpinning the potential of EDPA to be used in the high-temperature reservoirs acidizing.This work improved the thermal tolerance of VES in highly concentrated HCl solution,paving a feasible way for the acidization of high-temperature reservoir environments(~150℃).

Interaction of 4-aminosalicylic Acid and Surfactants in Aqueous Solutions Using UV-Vis Spectra and Steady-state Fluorescence Spectroscopy

The interactions of 4-aminosalicylic acid （4-ASA） and surfactants in aqueous solutions were investigated by using UV-Vis spectra and steady-state fluorescence spectroscopy.The results showed that the strongest peak at UV-vis spectra of 4-ASA aqueous solution in the presence of cationic surfactant and cetyltrimethyl ammonium bromide （CTAB） appeared at 206 nm and took a red shift from 206 nm to 221 nm with the increase of 4-ASA concentrations from 0.8×10-5 to 4.4×10-4 mol/L.Similarly,the strongest peak at UV-vis spectra of 4-ASA aqueous solution in the presence of nonionic surfactant and polyvinylpyrrolidone （PVP） appeared at 206 nm and took a red shift from 206 nm to 219 nm with the increase of 4-ASA concentrations from 0.8×10-5 to 4.4×10-4 mol/L.However,the similar phenomena did not appeared in the presence of anion surfactant,sodium dodecyl sulfate （SDS）,the UV-vis spectra of 4-ASA aqueous solution remained the same peak position and the peak value increased with the 4-ASA concentration increase.The results could be attributed to the electrostatic attraction between 4-ASA and CTAB or PVP,as well as the electrostatic repulsion between 4-ASA and SDS.Furthermore,the value of critical micelle concentration （CMC） of surfactants in the presence of 4-ASA was determined with Fluorescence method.The first and second CMC of CTAB was 1.2×10-4 M and 2.4×10-4 M,respectively.The first and second CMC of PVP was 1.2×10-4 M and 2.8×10-4 M.SDS realized the multiple micellizations to form multiple CMC.

Molecular origin for pH-responsive wormlike micelles of zwitterionic surfactants triggered by aromatic acid derivatives

Introduction of aromatic acid derivatives(AADs)into zwitterionic surfactants is an efficient method to prepare wormlike micelles with pH-controllable viscosity;however,the coincident molecular origin of AAD/zwitterionic surfactant binary mixtures remains unclear.Herein,the self-assembly of hydroxyl derivatives of benzoic acid(BA)and cetyldimethyl betaine(BS-16)mixtures in water was systematically assessed,and various factors,such as the molecular structure,molar ratio of AAD and BS-16,and solution pH,were investigated.The structure-property relationship of AAD/BS-16 binary mixtures was established,which provided the molecular origin for the effect of AAD on micellar microstructures and the pH-induced morphological transitions.The ortho-substituted hydroxyl moiety in the BA molecule facilitated the formation of larger wormlike micelles,whereas the effect of the meta-substituted moiety was less significant.The para-substituted hydroxyl moiety in BA did not favor micellar growth.This moiety exhibited similar characteristics to the increasing hydroxyl moiety number in the AAD molecules or solution pH where the negative effects of steric hindrance and electrostatic interactions of molecules in micelles aredominant.

A Simple and Rapid Method for the Detection of Non-Ionic Surfactants

A spectrophotometric approach for the detection of non-ionic surfactant (Triton X-100) has been proposed in this paper. This method does not involve extraction of the ion-associate with harmful solvents, but employs adhesion of the ion-association of potassium/non-ionic surfactants complex and tetraphenylporphyrin tetrasulfonic acid obtained by vigorous shaking. The adhered ion-associate was dissolved with water and its absorbance was measured. The sensitivity for Triton X-100 was determined to be 0.146 (expressed as absorbance of 1 mg/L solution). The adhesion tendency of ion-associate was found to be dependent on the water contact angle, which in turn was influenced by a high adhesion of the ion-associate and by low blank values. In this respect, a tetrafluo-roethylene vessel was found to be the most suitable for the detection of non-ionic surfactants. This spectrophotometrical method is simply and rapidly performed by a procedure based on mechanical shaking and can be employed to detect non-ionic surfactants containing more than 7 polyethylene oxide units.

Experimental investigation into L-Arg and L-Cys eco-friendly surfactants in enhanced oil recovery by considering IFT reduction and wettability alteration

Surfactant flooding is an important technique used to improve oil recovery from mature oil reservoirs due to minimizing the interfacial tension(IFT)between oil and water and/or altering the rock wettability toward water-wet using various surfactant agents including cationic,anionic,non-ionic,and amphoteric varieties.In this study,two amino-acid based surfactants,named lauroyl arginine(L-Arg)and lauroyl cysteine(L-Cys),were synthesized and used to reduce the IFT of oil–water systems and alter the wettability of carbonate rocks,thus improving oil recovery from oil-wet carbonate reservoirs.The synthesized surfactants were characterized using Fourier transform infrared spectroscopy and nuclear magnetic resonance analyses,and the critical micelle concentration(CMC)of surfactant solutions was determined using conductivity,pH,and turbidity techniques.Experimental results showed that the CMCs of L-Arg and L-Cys solutions were 2000 and 4500 ppm,respectively.It was found that using L-Arg and L-Cys solutions at their CMCs,the IFT and contact angle were reduced from 34.5 to 18.0 and15.4 mN/m,and from 144°to 78°and 75°,respectively.Thus,the L-Arg and L-Cys solutions enabled approximately 11.9%and 8.9%additional recovery of OOIP(original oil in place).It was identified that both amino-acid surfactants can be used to improve oil recovery due to their desirable effects on the EOR mechanisms at their CMC ranges.

Liquid Membrane Oscillation of Water/Oil/Water System Containing TTAB and Recognition to Amino Acids

The liquid membrane oscillation of a novel water（aqueous tetradecyl trimethyl ammoniumbromide,TTAB and alcohol solution）/oil（picric acid in chloroform solution）/water（aqueous glucose solution） system was investigated by means of a homemade device.The results show that the water（aqueous 7 mmol/L TTAB and 0.5 mol/L n-propanol solution）/oil（0.5 mmol/L icric acid in chloroform solution）/water（0.1 mol/L glucose solution） system performed sustained and stable oscillation at 30℃.The oscillation curve under optimized conditions is considered to be referent.Several oscillation curves were accumulated with the addition of different amino acids.The results showed that the novel system can recognize the added amino acids such as L-tryptophan,L-tyrosine,and D,L-tyrosine.And there is corresponding relationship between the change of curve shape and the quantity of amino acid added.

Synthesis and Properties of the Polymeric Surfactant Based on Maleamic Acid and Styrene

An alternative polymeric surfactant P（M3/St） was synthesized by solution polymerization of maleamic acid as hydrophilic monomer and styrene as hydrophobic monomer. Some factors that affect the yield and properties of the polymeric surfactant were investigated systemically. The surface tension of the polymeric surfactant reaches 37-38 mN/m. It is proved that the polymeric surfactant shows very good surface activity and emulsifying ability. The TG analysis shows that the temperature of the thermal degradation can reach 314.4 ℃. It will be used as a new type of polymeric surfactant.

Novel additives for the separation of organic acids by ion-pair chromatography

This paper proposes the use of novel surfactant additives for the separation of organic acids by ion-pair chromatography and studies the influences of surfactants on the chromatographic separation behaviors.Researches have been carried out on both silica gel matrix and polymer supporters in order to compare the two ordinary kinds of stationary phases,and the phenomenon is similar. Separation is based on differences in the stabilities of analyte-additive complexes in solution.Retention times of analytes can ...

Enhanced Oil Recovery by Injecting Oleic Acid as a Surfactant into the Porous Medium

Physico-chemical methods of improved oil recovery make it possible to increase oil production in deposits by injecting surfactants acting on various physical parameters. Oleic acid has an effect on the viscosity of the displacement fluid and the flow rate. Therefore, increasing the viscosity of the displacement fluid plays an essential role in improving the improved oil recovery. The physicochemical properties at the interface between petroleum and water are modified by oleic acid, lowering the viscosity of petroleum and increasing the viscosity of water, which facilitated the mobility of petroleum in the porous medium.

Photorheologically reversible micelle composed of polymerizable cationic surfactant and 4-phenylazo benzoic acid

A photorheologically reversible micelle composed of polymerizable cationic surfactant n-cetyl dimethylallyl am- monium chloride （CDAAC） and trans-4-phenylazo benzoic acid （trans-ACA） was prepared. The effects of molar ratio of CDAAC/trans-ACA, time of UV and visible light irradiation and temperature on the rheological properties of micellar system were investigated. The results show that before UV irradiation the system with an optimum CDAAC/trans-ACA molar ratio of 1.4 forms viscoelastic micelles at 45 ℃. After 365 nm UV irradiation, the viscos- ities of micelle systems with different concentrations at fixed molar ratio of 1.4 are decreased by 85%-95%. The CDAAC/trans-ACA （14 mmol. L- 1/10 mmol. L- 1 ） micelle system exhibits shear thinning property and its viscos- ity is decreased obviously with the increases of UV irradiation time less than I h. The rheological process during LIV irradiation for CDAAC/trans-ACA （14 mmol- L- 1/10 mmol. L 1） micelle proves that viscosity, elastic modulus G＇ and viscous modulus G＂ will reduce quickly with the UV light. Furthermore, the micelle system after 1 h UV- irradiation is able to revert to its initial high viscosity with 460 nm visible light irradiation for 4 h, and the micelle can be cycled between low and high viscosity states by repetitive UV and visible light irradiations. The LIV-Vis spectra of CDAAC/trans-ACA micelle indicate that its photosensitive theological properties are related closely to photoisomerization of trans-ACA to c/s-ACA.

Rapid semi-quantification of triacylglycerols,phosphatidylcholines,and free fatty acids in the rice bran of one grain

We developed a microplate assay method for determining the contents of triacylglycerols（TAGs）, phosphatidylcholines（PCs）, and free fatty acids（FFAs） in the rice bran of one grain using enzymatic reactions. In this method, enzymes from commercially available kits were used. Optimum reaction conditions were established. It was found that Nonidet P-40 was the optimal among the three surfactants used（Triton X-100, Tween 40, and Nonidet P-40） when lipid was dissolved in a reaction solution. Using this method, it was possible to quantify TAGs, PCs, and FFAs in concentration ranges of 7–150, 5–70, and 8–200 mg L-（–1）, respectively. Furthermore, when the TAG contents in the rice bran were measured, the values closely corresponded to those obtained by extracting from large amounts of rice bran. However, sufficient data on the PC and FFA contents in rice bran are not available for valid comparisons. Although this method can accurately quantify the TAG contents in the rice bran of one grain, the accuracy of the PC and FFA contents has not been verified. Hence, future study is necessary.

A critical review of self-diverting acid treatments applied to carbonate oil and gas reservoirs

Carbonate reservoirs generally achieved relatively low primary resource recovery rates.It is therefore often necessary to clean those reservoirs up and/or stimulate them post drilling and later in their production life.A common and basic carbonate reservoir cleanup technique to remove contaminating material from the wellbore is acidizing.The efficiency of acid treatments is determined by many factors,including:the type and quantity of the acid used;the number of repeated treatments performed,heterogeneity of the reservoir,water cut of the reservoir fluids,and presence of idle zones and interlayers.Post-treatment production performance of such reservoirs frequently does not meet design expectations.There is therefore much scope to improve acidizing technologies and treatment designs to make them more reliable and effective.This review considers acid treatment technologies applied to carbonate reservoirs at the laboratory scale and in field-scale applications.The range of acid treatment techniques commonly applied are compared.Differences between specific acid treatments,such as foamed acids,acid emulsions,gelled and thickened acid systems,targeted acid treatments,and acid hydraulic fracturing are described in terms of the positive and negative influences they have on carbonate oil production rates and recovery.Opportunities to improve acid treatment techniques are identified,particularly those involving the deployment of nanoparticles(NPs).Due consideration is also given to the potential environmental impacts associated with carbonate reservoir acid treatment.Recommendations are made regarding the future research required to overcome the remaining challenges pertaining to acid treatment applications.

高效液相色谱-紫外检测法同时测定洗面奶中4种N-月桂酰氨基酸表面活性剂

N-月桂酰氨基酸(NLAAs)表面活性剂与传统表面活性剂相比在安全性上具有明显的优势,应用领域日益增多。但由于NLAAs的紫外吸收较弱,采用高效液相色谱-紫外检测进行含量测定存在一定困难,一般使用示差折光指数检测器、蒸发光散射检测器等通用型检测器来进行检测。为解决这一难题,本研究通过优化流动相的组成,选择合适的色谱柱和检测波长,建立了高效液相色谱-紫外检测同时测定月桂酰谷氨酸(LG)、月桂酰甘氨酸(LC)、月桂酰丙氨酸(LA)、月桂酰肌氨酸(LS)4种NLAAs表面活性剂的方法。样品在乙腈-0.10%H_(3)PO_(4)水溶液(60∶40,v/v)中超声提取10 min,滤膜过滤后用高效液相色谱仪测定,以乙腈-0.10%H_(3)PO_(4)水溶液为流动相进行梯度洗脱,经Agilent Eclipse Plus C_(18)色谱柱(150 mm×4.6 mm,5μm)分离,在205 nm波长处进行检测。结果显示:4种NLAAs在2.0~800.0 mg/L范围内呈良好的线性关系,相关系数(r)均≥0.9995,检出限(LOD)为0.17~0.49 mg/L,定量限(LOQ)为0.57~1.63 mg/L。在0.60、4.50、15.00、24.00 mg/g 4个加标水平下,NLAAs的加标回收率在94.3%~107.4%范围内。采用该方法对5个洗面奶样品中的NLAAs进行含量测定,发现所有样品都含有一种或多种NLAAs化合物,NLAAs的总含量在64.58~97.01 mg/g范围内。该方法前处理简单,测试快速,方法精密度、准确性、稳定性良好,适于洗面奶中NLAAs的含量测定,也可为该类型表面活性剂原料纯度、合成产率检测及产品的质量控制提供有效的技术参考。

延长油田转向酸油层深部解堵室内评价

酸化常用于解除伤害和增加储层渗透率。在碳酸盐岩储层中,这一过程通常采用基于黏弹性表面活性剂(VES)的转向酸。VES转向酸配方可以对[H^(+)]和[Ca^(2+)]的变化做出响应,从而调节表面活性剂溶液的流变性。当黏度增加时,流体会改变其流动方向,形成虫洞。构建了酸液中和的体系,并使用2种商用转向酸进行了测试,研究了不同中和度下流体的流变性,模拟了流体在碳酸盐基质中流动和反应时的行为。此外,还研制了基于VES的新型响应性转向酸ZX,并研究了它们在不同[H^(+)]和[Ca^(2+)]下的线性和非线性流变性,并在岩心驱替实验中评估了其性能,实验结果表明新型转向酸形成了优势虫洞。

阴阳离子表面活性剂对煤层自转向酸液的性能影响及优选

针对煤矿粉尘污染严重问题,研究了煤层OAPB自转向酸液均匀布酸,从而提高煤体含水率,借助黏度、荷电性、官能团等方法研究了不同阴阳离子表面活性剂对自转向酸液增黏、润湿性能的影响规律,探究了性能变化的内部原因,并根据测试结果进行了优选。结果表明:阳离子表面活性剂会直接导致自转向酸液破胶,阴离子表面活性剂的添加使自转向酸液黏度增加;SSA/SDBS润湿性能较好,表面张力最低为24.12 mN/m;SSA/SDBS-16表面张力值总体较高,自身润湿性能差,对煤体的吸附性能也较弱;通过红外实验发现在SSA/SDBS作用下OAPB分子更倾向于形成氢键,并通过三轴渗流实验验证了自转向酸液的渗流效果。

解水锁剂的研究现状及展望

水锁效应是油气井生产的主要影响因素,尤其是对于低渗透储层影响更为显著。目前国内外学者在水锁损害机理、影响因素、解除方法、评价方法等方面做了大量研究,取得了较大进展。但是对于解水锁剂很少有系统性的归纳总结。因此,对现有的解水锁剂进行调研,通过了解各类解水锁剂的配方、性能评价方法和所取得的效果对后续解水锁剂的研究制备具有指导意义,在系统总结水锁的伤害机理和解水锁剂的作用机理的基础上,重点介绍了以改变润湿性、降低界面张力和恢复储层渗流能力为目标解除水锁伤害的酸液体系、表面活性剂体系和纳米体系,并对解水锁剂的评价方法进行总结归纳,提出了未来解水锁剂的发展趋势和研究重点。