Interfacial Tensions of Ethoxylated Fatty Acid Methyl Ester Solutions Against Crude OilJournal of Surfactants and Detergents - Tập 20 - Trang 961-967 - 2017
Miao Liu, Hongbo Fang, Zhiqiang Jin, Zhicheng Xu, Lei Zhang, Lu Zhang, Sui Zhao
The dynamic interfacial tension (IFT) of ethoxylated fatty acid methyl ester solutions against n-alkanes, kerosene, and diluted heavy oil have been investigated by spinning drop interfacial tensiometry. The influences of ethylene oxide (EO) groups and alkyl chain length on IFT were investigated. The experiment results show that the water solubility decreases with an increase in alkyl chain length or a decrease in EO groups. The ability to lower the interfacial tension against hydrocarbons improves with both increasing alkyl chain length and EO group at the best hydrophilic-lipophilic balance, which can be attributed to the enhancement of the interfacial hydrophobic interactions and the rearrangement of interfacial surfactant molecules. The mixed adsorption of surfactant molecules and surface-active components may reduce IFT to a lower value. C18=E3 shows the best synergism with surface-active components. However, the IFT values against pure crude oil are obviously higher than those against hydrocarbons, which may be caused by the nature of heavy oil.
Synthesis and Physicochemical Properties of Silicon-Terminated Octyl/Decyl Polyethylene Oxide as Novel Low-Foam Penetrating AgentsJournal of Surfactants and Detergents - Tập 17 - Trang 759-765 - 2013
Qing-hua Niu, Zhi-qiang He, Yun Fang
Low-foam penetrating agents have been sought after for many industrial applications. In this paper, we were aiming at a low-foam penetrating agent with excellent wetting ability and hydrolysis resistance, various silicon-terminated penetrating agents were designed and synthesized starting from a popular commercial penetrating agent, octyl/decyl polyethylene oxide (OEO). All the products present much better low-foam performances than that of the precursor OEO. Statistically, multi-OEO substituted products present the best low-foam performance but a slightly weaker wetting ability. Except octyl/decyl polyethylene oxide trimethyl silicane, all the other five products maintain excellent wetting ability and show good hydrolysis resistance at neutral pH and ambient temperature. Di(octyl/decyl polyethylene oxide) dimethyl silicane is the preferred low-foam penetrating agent based on its structure–performance and cost, which reduced the foam volume of OEO from 75 to 4 mL (on the 100 mL volume base) at neutral pH and ambient temperature with a similar wetting ability.
An alternative synthesis and mobile phase ion chromatography of alkanedisulfatesJournal of Surfactants and Detergents - Tập 5 - Trang 359-362 - 2002
James F. Cormier, Andrea Dower, Sheryl Boucher, Shamus Blair, D. Gerrard Marangoni, Truis Smith-Palmer
Preparation of alkane disulfates using chlorosulfonic acid results in a crude product containing significant amounts of chloride, sulfate, and hydroxyalkanesulfates. This paper describes an alternative synthesis using trimethylamine:sulfur dioxide complex in anhydrous pyridine. Workup with sodium hydroxide and washing in acetone results in a crude product with less than 1% inorganic impurity and ∼0–3% hydroxyalkanesulfate. Recrystallization from acetone reduces the inorganic impurity to less than 0.1%. Alkanedisulfates can be separated from the corresponding hydroxyalkanesulfates, chloride, and sulfate using mobile phase ion chromatography with tetrabutylammonium hydroxide (TBAOH) as the ion-pairing agent and acetonitrile as the organic modifier. With the crude octanedisulfate and decanedisulfate product mixes, the alkanedisulfate is retained more strongly by the ion-pairing effect; but with the tetradecane species, hydrophobic interaction dominates and the tetradecanedisulfate elutes before the hydroxytetradecanesulfate. The choice of acetonitrile gradient and TBAOH is particularly important for the separation of the dodecane derivatives because the opposing effects of polarity (hydrophobic effect) and electrostatic interaction with TBAOH are of similar strength.
Corrosion inhibition of triethanolammonium bromide mono- and dibenzoate as cationic inhibitors in an acidic mediumJournal of Surfactants and Detergents - Tập 8 - Trang 283-287 - 2005
Nabel A. Negm, Salwa M. I. Morsy
A weight loss technique was used to determine the corrosion inhibition efficiency of synthesized alkyl mono-and dibenzoate triethanolammonium bromide derivatives (TEAMB, TEADB) in an acidic medium (2 N HCl) at different doses (50, 100, and 200 ppm). The results showed that monoderivatives had a higher corrosion inhibition efficiency than diderivatives. The results were correlated with several factors, including the alkyl chain length of the hydrophobic chains, interfacial tension (IT), critical micelle concentration (CMC), and adsorption free energy of these inhibitors. Increasing the geometric length of the alkyl chains in the synthesized inhibitors had an increasing effect on their corrosion inhibition efficiency, whereas decreasing the CMC and IT had an increasing effect on their tendency toward corrosion inhibition. The number of hydrophobic chains attached to the inhibitor molecules had a vital influence on their efficiency as corrosion inhibitors.
Nhũ tương dầu thực vật thân thiện với môi trường sử dụng chất hoạt động bề mặt kéo dài và liên kết Dịch bởi AI Journal of Surfactants and Detergents - - 2009
D. Linh, Anuradee Withayyapayanon, Jeffrey H. Harwell, David A. Sabatini
Tóm tắtViệc hình thành nhũ tương dầu triglyceride ở điều kiện môi trường (nhiệt độ và áp suất) và không có sự bổ sung dầu đồng và/hoặc rượu là một thách thức lớn. Các pha không mong muốn, chẳng hạn như nhũ tương vĩ mô, tinh thể lỏng và các pha bọt, thường gặp phải khi định hình nhũ tương triglyceride. Mục đích của nghiên cứu này là điều tra việc sử dụng các chất hoạt động bề mặt kéo dài, các liên kết ưa dầu, và các liên kết ưa nước trong việc tăng cường sự hòa tan của triglyceride và giảm sức căng bề mặt. Chúng tôi đã nghiên cứu hai loại chất hoạt động bề mặt kéo dài, đó là sulfate polypropoxylated alkyl dạng thẳng (LAPS) và sulfate ethoxylated polypropoxylated alkyl dạng thẳng (LAPES). Các liên kết được đánh giá bao gồm oleyl alcohol (liên kết ưa dầu), natri monometyl và dimethyl naphthalene sulfonate (SMDNS), và polyglucoside (liên kết ưa nước). Các loại dầu được nghiên cứu bao gồm dầu ô liu, dầu đậu phộng, dầu đậu nành, dầu cải canola và dầu hướng dương. Ảnh hưởng của nồng độ điện phân đến hành vi pha nhũ tương đã được nghiên cứu. Biểu đồ “cá” của nhũ tương đã được thu hoạch bằng cách vẽ biểu đồ nồng độ tổng của chất hoạt động bề mặt và liên kết so với nồng độ điện phân. Chúng tôi đã có thể tạo ra các nhũ tương triglyceride loại Winsor I, II, III và IV ở điều kiện môi trường và mà không cần bổ sung dầu đồng hoặc rượu chuỗi ngắn và trung bình. Nhũ tương triglyceride loại Winsor III và IV đặc biệt hữu ích trong nhiều ứng dụng như mỹ phẩm, chiết xuất dầu thực vật và phục hồi đất.
Enlargement of Nanoemulsion Region in Pseudo‐ternary Mixing Diagrams for a Drug Delivery SystemJournal of Surfactants and Detergents - Tập 17 Số 1 - Trang 49-58 - 2014
Ziheng Wang, Rajinder Pal
AbstractThe purpose of this research was to develop the pseudo‐ternary mixing diagrams for a potential drug delivery system consisting of vitamin E (potential drug) + soybean oil + surfactant + co‐surfactant (anhydrous glycerol) + water. The potential drug (vitamin E) was loaded in the oil phase. The effects of different surfactants (pure and mixed) on the mixing diagrams, especially on the nanoemulsion region, were investigated. The influence of the drug loading level on the mixing diagrams was also determined. The surfactants studied were polyethoxylated (20) sorbitan monolaurate, polyethoxylated (20) sorbitan monooleate, polyethoxylated (35) castor oil and their mixtures. The size (area) of the nanoemulsion region of the mixing diagrams was found to be dependent on the type of surfactant used and the loading level of the drug (vitamin E).
So sánh sự tự lắp ráp của biosurfactant surfactin ở giao diện lỏng-khí với các chất hoạt động bề mặt tổng hợp Dịch bởi AI Journal of Surfactants and Detergents - Tập 19 - Trang 645-652 - 2016
Sagheer A. Onaizi, M. S. Nasser, Nasir M. A. Al-Lagtah
Nghiên cứu này đã điều tra sự hấp phụ của surfactin, một biosurfactant lipopeptide, tại giao diện lỏng-khí. Mật độ hấp phụ tối đa và bản chất cũng như mức độ tương tác ngang giữa các phân tử surfactin đã được hấp phụ tại giao diện được ước tính từ dữ liệu căng bề mặt bằng cách sử dụng mô hình Frumkin. Thông tin định lượng thu được từ mô hình Frumkin cũng được so sánh với những thông tin thu được từ phương trình Gibbs và mô hình Langmuir–Szyszkowski. Phân tích sai số cho thấy sự phù hợp tốt hơn giữa các giá trị thực nghiệm và giá trị tính toán dựa trên mô hình Frumkin so với hai mô hình kia. Sự hấp phụ của surfactin tại giao diện lỏng-khí cũng được so sánh với sự hấp phụ của các chất hoạt động bề mặt tổng hợp anion như natri dodecylbenzenesulfonate (SDBS) và phi ion như ether monotetradecyl octaethylene glycol (C14E8). Đã ước tính rằng diện tích mà một phân tử surfactin chiếm tại giao diện lớn hơn khoảng 3 lần và 2.5 lần so với diện tích mà các phân tử SDBS và C14E8 lần lượt chiếm. Tương tác giữa các phân tử biosurfactant anion (surfactin) đã được ước tính là hấp dẫn, trái ngược với tương tác đẩy nhẹ giữa các phân tử SDBS đã được hấp phụ.
#Surfactin #biosurfactant #giao diện lỏng-khí #mô hình Frumkin #SDBS #C14E8 #hấp phụ
Influence of the Mixed Propoxy/Ethoxy Spacer Arrangement Order and of the Ionic Head Group Nature on the Adsorption and Aggregation of Extended SurfactantsJournal of Surfactants and Detergents - Tập 13 - Trang 451-458 - 2010
Ana M. Forgiarini, Cesar Scorzza, Josmary Velásquez, Francia Vejar, Emérita Zambrano, Jean-Louis Salager
Two families of extended surfactants were prepared with the same head groups (carboxylate, sulfate, disodium phosphate) and different intermediate spacer structures. In one there was an average of 7 propylene oxide groups on the side of the tail and an average of 7 ethylene oxide groups on the side of the head, to produce a sequence of two different polarity segments. In the other case the spacer contained the same average numbers of propylene and ethylene oxide groups but in some homogeneous arrangement. The intermediate spacer structure, without ionic head group and in the cases of the carboxylate and sulfate extended surfactants, had a packing density reduction which is associated to the homogeneously alkoxide arrangement in the spacer. Such an arrangement was found to produce about 20% more surface area at the interface, apparently because it results in some plumpness due to the spacer folding to remain close to the interface. Both the critical micelle concentration and occupied interfacial area of the extended surfactant increased with the ionization of the anionic group associated with the electrostatic repulsion effect.
Investigation of Micellization and Vesiculation of Conjugated Linoleic Acid by Means of Self-Assembling and Self-CrosslinkingJournal of Surfactants and Detergents - Tập 18 - Trang 179-188 - 2014
Ye Fan, Yun Fang, Lin Ma, Hang Jiang
Bioactive and biocompatible conjugated linoleic acid (CLA) has been only considered as a food or medicine ingredient due to its rare natural occurrence. In this work, the surface activities and pH-induced self-assembling behaviors of the semi-synthetic CLA molecules into micelles or vesicles were systematically investigated. First, the self-assembling of CLA was studied in detail, and it was found that aside from temperature and ionic strength, pH is the prominent factor affecting the self-assembling of CLA. Moreover, stable CLA ufasomes (unsaturated fatty acid liposomes) in uniform size were obtained by self-crosslinking of the CLA ufasomes, and the morphologies of the crosslinked CLA assemblies were recorded by transmission electron microscopy, which made known the pH-induced formation of the CLA ufasomes or the CLA micelles. The crosslinked CLA assemblies presented improved properties such as a higher calcium stability, a lower lime soap dispersing requirement and a better solubilization ability than that of the CLA molecules themselves or the pre-crosslinked linoleic acids. These investigations could be helpful for comprehensively understanding effects of environment factors on self-assembling behaviors of conjugated fatty acids and responsive polymerization of polymerizable surfactants.
Purification and Characterization of Highly Alkaline Lipase from Bacillus licheniformis MTCC 2465: and Study of its Detergent Compatibility and ApplicabilityJournal of Surfactants and Detergents - Tập 17 Số 5 - Trang 889-898 - 2014
Limpon Bora
AbstractAn extracellular alkaline lipase from Bacillus licheniformis MTCC 2465 has been studied and analyzed for its applicability as a detergent additive. The lipase obtained from Bacillus licheniformis MTCC 2465 was purified by ammonium sulfate fractionation and gel filtration chromatography. The enzyme was precipitated with a 60 % saturated ammonium sulfate fraction showed 6.73 fold purification with the fold purification of 10.4 and specific activity of 398 U/mg of protein with gel filtration chromatography. The optimal pH and temperature for activity were 10 and 60 °C respectively. The enzyme was found to be stable in the pH range of 8–11 with 90 % retention of activity at pH 11. The enzyme retained 90 % activity at 60 °C and 70 % of activity at 70 °C for 1 h. The enzyme activity was maximally enhanced by Hg2+ followed by Co2+ and Fe2+. The lipase was found to be stable in organic solvents with maximum stability in acetone followed by ethanol. The lipase exhibited remarkable stability in the presence of commercial detergents and found to be stable in bleaching agents. Wash performance analysis resulted in improvement of 10 % more grease removal ability of the present lipase in comparison to commercially available lipase.
