Environmentally Friendly Nonionic Surfactants Derived from Jatropha Oil Fatty Acids as Inhibitors for Carbon Steel Corrosion in Acidic Medium

The inhibition effect of four novel environmentally friendly inhibitors (derived from vanillin and a fatty acid mixture obtained from the hydrolysis of Jatropha oil) on carbon steel corrosion in 0.5 M H₂SO₄ was investigated by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The results show high efficiency of the inhibitors. The inhibition efficiency increases by increasing the polyethylene glycol chain length and the inhibitor concentration. From polarization curves, the inhibitors act as cathodic inhibitors. EIS spectra display a large capacitive loop at high frequencies followed by a large inductive loop at low frequencies. Environmental study shows inhibitors tendency towards biodegradation by the action of microorganisms after 28 days.     

Evaluation of Some Nonionic Surfactants Derived From Vanillin as Corrosion Inhibitors for Carbon Steel During Drilling Processes

Four eco‐friendly nonionic surfactants based on vanillin were investigated as corrosion inhibitors against carbon steel dissolution during the drilling process in the oil field. The corrosion inhibition efficiencies of the tested compounds were determined using weight loss, electrochemical polarization, and electrochemical impedance techniques. The data obtained show that the nonionic surfactants prevent the corrosion of drilling tools and their inhibition efficiency increased with an increase in their concentration. Tafel curves revealed that the surfactants under study act as mixed inhibitors. The adsorption of the inhibitors on carbon steel surface decreases the double‐layer capacitance. The inhibition efficiencies of the surfactants were influenced by their chemical structure and surface activity.     

Evaluation of Some Nonionic Surfactants Derived from Tannic Acid as Additives for Water‐Based Mud

Water‐based mud is the most‐used mud for oil and gas exploration and is generally considered to be more environmentally friendly than oil‐based or synthetic‐based mud. Therefore in this study we focused on water‐based mud and a series of nonionic surfactants derived from tannic acid was evaluated as additives for water‐based muds. The rheological properties for formulated water‐based muds contain nonionic additives at different temperatures were investigated including: apparent viscosity, plastic viscosity, yield point, gel strength, thixotropy and filtration properties. In addition to the relation between shear stress and shear rate were presented at different temperatures. The results of the studied nonionic surfactant showed improvements in the rheological properties when used as additives for water‐based mud formulation.     

Corrosion Inhibition Efficiency,Electrochemical and Quantum Chemical Studies of Some New Nonionic Surfactants for Carbon Steel in Acidic Media

In this work, three types of nonionic surfactant as corrosion inhibitors were synthesized. The chemical structure of the prepared inhibitors was confirmed using FT‐IR and ¹H‐NMR spectroscopy. The surface tension and thermodynamic properties of these inhibitors were investigated. The corrosion inhibition efficiency of these surfactants was investigated on a carbon steel surface in 1 M HCl solution by weight loss and electrochemical measurements. Untreated and treated steel surfaces were characterized by scanning electron microscopy. Results show that the inhibition efficiency of the prepared inhibitors increases with increasing the ethylene oxide units. Also, the potentiodynamic polarization curves indicated that the investigated inhibitors behave as a mixed type inhibitor. Adsorption of these surfactants on the carbon steel surface was found to obey Langmuir's adsorption isotherm. The computed quantum chemical properties viz., electron affinity (EA), highest occupied molecular orbital (E_HOMO), the lowest unoccupied molecular orbital (E_LUMO), energy gap ΔE = E_HOMO ? E_LUMO, dipole moment (μ), polarizability and total energy (E_T) show good correlation with experimental inhibition efficiency.     

Novel Biobased Nonionic Surfactants: Synthesis,Surface Activity and Corrosion Inhibition Efficiency Against Aluminum Alloy Dissolution in Acidic Media

Four nonionic surfactants were prepared from the reaction of propylene oxide with oleic acid, linoleic acid, and the free fatty acid mixture from hydrolysis of jatropha oil. The chemical structures of the prepared surfactants were confirmed using IR and NMR spectroscopy. The surface activities of the prepared surfactants were dependent on the polypropylene oxide chain length and also on the nature of the alkyl chains. The nonionic surfactants were evaluated at different concentrations as corrosion inhibitors against the corrosion of Al 6061 aluminum in 2 M HCl solution. The corrosion inhibition tendencies of the surfactants were completely dependent on the fatty acid ratio in the jatropha oil and also on the polypropylene oxide chain length. The corrosion inhibition efficiencies of the surfactants were correlated to their chemical structure and their surface activities.     

Synthesis, Characterization, Biodegradation and Evaluation of the Surface Active Properties of Nonionic Surfactants Derived from Jatropha Oil

Four nonionic surface active agents were synthesized using the fatty acids obtained from the hydrolysis of Jatropha oil. The fatty acids obtained contained different fatty acids including: palmitic, stearic, oleic, linoleic and linolenic acids in different proportions. The chemical structures of the obtained surfactants were characterized using elemental analysis and FTIR spectroscopy. The surface activities of the different surfactants were determined using surface and interfacial tension measurements. The surfactants showed good surface and interfacial activities, which are dependent on their chemical structures. Thermodynamic parameters of adsorption and micellization confirmed these results. The biodegradation tests in river water showed that the surfactants are readily biodegradable, and reached the European standards after 24 days. Surfactants containing longer nonionic chains formed stable emulsions with paraffin oil, while shorter chains exhibit a lower emulsion stability performance.     

2-Ethylhexanol Derivatives as Nonionic Surfactants: Synthesis and Properties

The synthesis and basic properties of 2‐ethylhexanol based innovative nonionic surfactants are described in this paper. 2‐Ethylhexanol as an available and relatively inexpensive raw material was used as the hydrophobe source modified by propoxylation and followed by polyethoxylation. As the result, six series of 2‐ethylhexyl alcohol polyalkoxylates (EHP_mE_n) were obtained with three steps of propoxylation, each followed by polyethoxylation and two series only with polyethoxylation (EHE_n). Two different catalysts were used, a dimetalcyanide and KOH. Values of average conversion rates and chemical content of the obtained products (GC, TG and GPC techniques) were compared. The influence of the applied catalyst and polyaddition degree on the homologue distribution, reactant conversion and amount of byproducts is discussed. The basic physicochemical parameters including refractive index, solubility in polar media, foaming properties and wettability were investigated and compared. Furthermore, surface activity parameters, i.e. surface tension (γ_CMC) and critical micelle concentrations were determined. Results are compared to C_12–14 alcohol ethoxylates (LaE_n). Accordingly, it was found that the studied 2‐ethylhexyl alcohol based compounds are effective, low foaming nonionic surfactants.     

Mono‐, Di‐ and Tetra‐Cationic Surfactants as Carbon Steel Corrosion Inhibitors

Corrosion inhibition of three new synthesized cationic surfactants, N‐(2‐(((Z)‐4‐(pyridin‐4‐yl)but‐3‐en‐1‐yl)amino)ethyl)‐N‐(2‐((E)‐(pyridin‐4‐ylmethylene)amino)ethyl)dodecan‐1‐aminium bromide I(4N), N¹,N²‐didodecyl‐N¹‐((Z)‐4‐(pyridin‐4‐yl)but‐3‐en‐1‐yl)‐N²‐(2‐((E)‐(pyridin‐4‐ylmethylene)amino)ethyl)ethane‐1,2‐diaminium bromide II(4N) and 1‐dodecyl‐4‐((E)‐((2‐(dodecyl(2‐(dodecyl((Z)‐4‐(1‐dodecylpyridin‐1‐ium‐4‐yl)but‐3‐en‐1‐yl)ammonio)ethyl)ammonio)ethyl)imino)methyl)pyridin‐1‐ium bromide IV(4N) on carbon steel was investigated by weight loss, electrochemical impedance spectroscopy and polarization measurements. Results show that the synthesized cationic surfactants inhibit corrosion of carbon steel in 1 M HCl. The inhibitive action occurs by virtue of adsorption on the metal surface following a Langmuir adsorption isotherm model. Polarization curves reveal that the investigated cationic surfactants can be classified as mixed inhibitor types. The variations in the corrosion inhibition efficiency between three cationic surfactants are correlated with their chemical structures, with more hydrophobic surfactants yielding higher inhibition efficiency.     

Synthesis and Characteristics of Dodecyl Isopropylolamine and Derived Surfactants

Dodecyl isopropylolamine has been synthesized on the basis of dodecylamine and propylene oxide. The structure of dodecyl isopropanolamine has been determined by X‐ray diffraction, elemental analysis, IR‐ and NMR‐spectroscopic methods. Ionic surfactants have been synthesized by interaction of dodecyl isopropylolamine with various acids (HCl, HBr, acetic and propionic) and alkyl halides (methyl iodide, ethyl bromide and n‐propyl bromide). Colloidal‐chemical parameters, petroleum‐collecting and petroleum dispersing capacities of the synthesized cationic surfactants have been studied.     

Environmentally Friendly Nonionic Surfactants Derived from Tannic Acid: Synthesis, Characterization and Surface Activity

In order to discover new and safe surfactants with regard to the environment, new environmentally friendly nonionic surface active agents were synthesized by the reaction of tannic acid (as a natural product presents in several plants) and polyethylene glycol fatty acids containing different numbers of ethylene glycol units. The fatty acids were dodecanoic, hexadecanoic, octadecanoic and oleic acids. The chemical structures of the synthesized surfactants were confirmed using elemental analysis, infrared and ¹H-NMR spectroscopy. The molecular weights of the synthesized surfactants were determined using viscosity measurements and gel permeation chromatography. The surface properties of these surfactants were determined using surface tension measurements. The chemical structure?Csurface activity relationship of these surfactants showed a strong dependence of the surface activity on their chemical structures including the hydrophobic chains and the number of ethylene glycol units incorporated in the molecules. The free energy of micellization of the surfactants in their solutions showed their tendency towards micellization in the bulk of their solutions, while the free energy of adsorption showed their high tendency towards adsorption at the air?Cwater interface.     

金属在酸性介质中有机缓蚀剂的研究进展

概述了在酸性条件下碳钢有机缓蚀剂的种类及研究方法的进展,着重探讨了有机缓蚀剂在酸性条件下的缓蚀机理,简述了几种常见的电化学测试方法及量子化学法、人工神经网络、激光拉曼光谱等高新手段在腐蚀领域中的应用,最后对缓蚀剂的发展作了展望。     

Synthesis and Surface Properties of Polyether-Based Silicone Surfactants with Different Siloxane Groups

A series of polyether-based silicone surfactants with different hydrophobic chains (trimethylsiloxy, triethylsiloxy, and triisopropylsiloxy) were synthesized. The molecular structures were confirmed using ¹H nuclear magnetic resonance (NMR), ¹³C NMR, ²⁹Si NMR, and fourier transform infrared spectroscopy (FT-IR). The effect of the siloxane groups on the physicochemical properties, surface tension (γ), critical micelle concentration (CMC), surface tension at the CMC (γ_CMC ), adsorption efficiency (pC₂₀), surface pressure at the CMC (π_CMC ), maximum surface excess (Γ_max ), single silicone surfactant molecule at the air/water interface (A_min ), and the standard free energy of adsorption (), of the polyether-based silicone surfactants was investigated. Results indicate that the polyether-based silicone surfactants can reduce the surface tension of water to approximately 25–31 mN m⁻¹ and the surface activity of silicone surfactants is enhanced with increasing branched trimethylsiloxyl and sterically hindered siloxane groups.     

Synthesis and Evaluation of Nonionic Polymeric Surfactants Based on Acrylated Polyethylene Glycol

A novel series of six nonionic polymeric surfactants were prepared by polymerization of acrylated poly(ethylene glycol) (PEG, molecular weight MW = 400, 600 and 2,000) and allyl ester of long chain fatty acid chloride (decanoyl and lauroyl chloride). The unique structural features of these surfactants were confirmed by different spectroscopic tools (IR and ¹H NMR). The surface properties of these compounds such as surface tension, interfacial tension, emulsion stability, wetting power, foam height, solubilization and dispersant properties in disperse dye systems were determined and evaluated. A comparison study was done between the chemical structures and surface properties of such compounds. Biodegradability and stability to hydrolysis in acidic and alkaline media were also determined and evaluated.     

Synthesis, Surface and Thermodynamic Properties of Substituted Polytriethanolamine Nonionic Surfactants

Three series of nonionic surfactants derived from polytriethanolamine containing 8, 10, and 12 units of triethanolamine were synthesized. Structural assignment of the different compounds was made on the basis of FTIR and ¹H‐NMR spectroscopic data. The surface parameters of these surfactants included critical micelle concentration (CMC), surface tension at the CMC (γ_CMC), surfactant concentration required to reduce the surface tension of the solvent by 20 mN m^?1 (pC₂₀), maximum surface excess (Γ_max), and the interfacial area occupied by the surfactant molecules (A_min) using surface tension measurements. The micellization and adsorption free energies were calculated at 25 °C.     

Retracted: Synthesis,Characterization, and Surface Activities of Polymeric Cationic Thiol Surfactants in Aqueous Medium

A series of cationic polyurethane surfactants [PQ_8-18] were synthesized by the reaction of alkyl bromoacetate (namely: octyl-, decyl-, dodecyl-, tetradecyl-, hexadecyl-, and octadecyl bromoacetate) as quaternizing agents and modified polyurethane contains tertiary amine species. Modified polyurethane was prepared by the reaction of toluene diisocyanate (TDI) and triethanol amine monomercaptoacetate. The chemical structures of the prepared surfactants were confirmed using elemental analysis, Fourier transform infrared spectroscopy (FTIR), and Proton nuclear magnetic resonance (¹H NMR) spectroscopy. The molecular weight measurements of the prepared polymers showed that the segments of each polymer contain average 10 units of the urethane-triethanol amine mercaptoacetate. The surface activities of the prepared surfactants including: surface tension (γ), effectiveness ( π_cmc), concentration at micelle formation (CMC), efficiency (Pc₂₀), maximum concentration at the interface (Γ_max), and the average area occupied by each surfactant molecule at the interface at equilibrium ( A _min) of surfactants solutions were established at 25°C. The surface tension and the critical micelle concentration values of the prepared surfactants were gradually decreased by the gradual increase of their alkyl chain length. The prepared cationic surfactants showed efficient activity as inhibitors for dissolution of carbon steel in an acidic medium and also as a biocide against the growth of bacteria, fungi, and yeast.     

Novel Nonionic Polyurethane Surfactants and Ag Nanohybrids: Influence of Nonionic Polymeric Chains

Five novel nonionic surfactants were prepared by the reaction of polyethylene glycol of different molecular weights with toluene diisocyanate. The obtained polyurethane polymers were reacted with oleic acid to obtain the nonionic polyurethane surfactants. The structures of the synthesized compounds were determined by using: Fourier Transform Infrared Spectroscopy (FTIR) and their average molecular weights by means of GC analysis. Silver nanohybrids of the nonionic polyurethane surfactants were prepared via physical combination by chemically prepared silver nanoparticles. The silver nanohybrids were determined using: UV, TEM, and DLS spectroscopy. The influence of the nonionic chain length (polyethylene glycol chains) on the surface activity of the synthesized nonionic polyurethane oleate surface active agents and their silver nanohybrids was studied. The results of surface activity of the nonionic polyurethanes oleate and their nanohybrids showed an increase in the critical micelle concentration by decreasing the polyethylene glycol chain lengths. The nanohybrids were also more surface active. Longer polyethylene glycol chains provide good protection for the formed silver nanoparticles than the shorter chains.     

Synthesis,Characterization, Surface and Biological Activity of Diquaternary Cationic Surfactants Containing Ester Linkage

Two series of diquaternary cationic surfactants designated as E9Nm and E11Nm having two different alkyl chains in their chemical structure were synthesized. The chemical structures of these surfactants were confirmed using elemental analysis, FTIR and ¹H‐NMR spectra. The surface activities of the different surfactants were determined using surface and interfacial tension at 25 °C. The surface parameters including: critical micelle concentration, effectiveness, efficiency, maximum surface excess and minimum surface area were determined. The surface activities of the cationic surfactants were correlated with their chemical structure. The surface activities of the surfactants increased with increasing the hydrophobic chain length. The adsorption and micellization tendencies of the surfactants in solution were determined using the free energies of adsorption and micellization. The synthesized surfactants were evaluated as biocides against bacteria and fungi. Biocidal activity data showed that a gradual increase in the hydrophobic chain length of the surfactant molecules gradually increases the efficiency of these surfactants as biocides.     

Synthesis,Characterization, and Evaluation of Ethoxylated Lauryl-Myrisityl Alcohol Nonionic Surfactants as Wetting Agents,Anti-Foamers,and Minimum Film Forming Temperature Reducers in Emulsion Polymer Lattices

Two nonionic FAEO (fatty alcohol ethoxylated) surfactants with varying solubility were obtained by the reaction of lauryl-myrisityl alcohol (LMA) with ethylene oxide to yield lauryl-myristyl/alcohol ethoxylated with 3 and 31 mol of ethylene oxide by changing the length of polyethylene glycol segment. The prepared surfactants, designated as LMAEO-3 and LMAEO-31, were characterized for their structures using spectroscopic measurements; in addition, their surface properties were investigated. The results indicated that LMAEO-31 exhibits excellent surface activity. Evaluation of the surfactants as wetting agents, anti-foamers, and minimum film forming temperature (MFFT) reducer in emulsion polymer lattices achieved promising results indicating high performance in the mentioned industrial applications.