ABSTRACT Using the new foam dust suppression technology aims to effectively control construction dust. Based on preliminary experiments, we studied foam preparation and the stability of dust‐suppressing foam. The results show: (1) Through orthogonal experiments, the optimal foam formula was determined to be 1% K12A by mass concentration, 0.6% glycerol, 1.5 g/L PVA, which can maintain a water content above 4% for up to 8 days; (2) Simulated dust suppression tests show a dust reduction efficiency of 45.45%, indicating a certain dust suppression effect, because the liquid formed by foam collapse can penetrate and wet the dust, and smaller dust particles aggregate and stick together, significantly increasing the apparent particle size; (3) The stability of foam covering the dust is influenced by the combined effect of the environmental field and dust interface characteristics. We found that different factors affect foam stability in different ways: the greater the wind speed, the faster the foam collapses and the worse the stability; the higher the environmental temperature, the faster the foam breaks; the higher the dust moisture content, the slower the foam collapse rate, and the better the foam stability. This research provides theoretical support for the practical application of foam dust suppression technology.
ABSTRACT The effective separation of water from crude oil is essential for maintaining oil quality, maximizing production performance, and mitigating operational issues within petroleum processes. In this work, four ionic surfactants were synthesized and evaluated as demulsifiers of a water‐in‐oil (W/O) emulsion obtained from a sample of Mexican heavy crude oil to study the effect of the anion chain length derived from naturally abundant saturated fatty acids. Bottle tests, centrifuge tests, and microwave irradiation tests were conducted to track the kinetics of demulsification using the synthesized surfactants. The centrifuge and microwave tests significantly reduced the emulsion breaking time compared to the traditional bottle test, achieving more than 91% water removal. The ionic surfactant tetrabutylammonium stearate showed the best performance as a demulsifier. Factors influencing the emulsion‐breaking process were discussed, including the carboxylate anion chain length, demulsifier concentration, heating time, and the physical method used to enhance demulsifier performance (conventional heating, dielectric heating, and centrifugation).
ABSTRACT In this study, the synthesis, characterization, and textile application performances of poly(ethylene glycol) (PEG)‐based next generation Gemini surfactants of the type C m ‐PEGn(Cl/Br)Es‐C m were investigated. Both conventional and microwave (MW) assisted methods were employed during the synthesis step and subsequently compared. It was determined that the MW method significantly reduced the reaction time (by approximately 50%) and enhanced efficiency. Structural verification of the synthesized compounds was conducted using FTIR, 1 H NMR, and TGA analyses. In the physicochemical investigations of the synthesized Gemini surfactants, the effects of hydrophobic tail length (C 12 –C 18 ) and hydrophilic spacer distance (PEG200–400) on the critical micelle concentration (CMC) were examined. The lowest CMC value of 4 mM was obtained with the long‐chain hydrophobic derivatives. In textile applications, the crease recovery angle (CRA) values imparted to the fabric by the synthesized Gemini surfactants through padding and exhaustion methods were measured. The results indicate that increasing hydrophobicity and decreasing spacer chain length significantly enhance the CRA performance as a mathematical representation of fabric hand in both the weft and warp directions of the fabric. These findings demonstrate that the developed Gemini surfactants have the potential to be utilized as functional softeners in textile finishing processes.
ABSTRACT In this study, the adsorption behavior of pharmaceutical compounds such as promethazine, triflupromazine, trimethoprim, carbamazepine, and ibuprofen on activated carbon in aqueous media was investigated. The effects of ionic surfactants (sodium dodecyl sulfate and dodecyl trimethyl ammonium bromide) on this process were also evaluated. The effects of parameters such as contact time, initial concentration, and temperature on adsorption efficiency were systematically investigated. Lagergren first‐order and pseudo‐second‐order models were applied in kinetic analyses; the results obtained showed better fit to the pseudo‐second‐order model. The Giles curves obtained from isotherm studies exhibited an L‐shaped character, and the equilibrium data fit the Langmuir model better than the Freundlich isotherm. The calculated adsorption capacities followed the order ibuprofen > carbamazepine > trimethoprim > triflupromazine > promethazine. The presence of surfactants did not alter the equilibrium time but significantly affected the adsorption capacity. Furthermore, the desorption of promethazine from activated carbon was studied using low molecular weight alcohols (methanol, ethanol, and isopropanol); the highest desorption rate was obtained with a solution containing 40% isopropanol in 24 h. Successive adsorption–regeneration cycles were successfully performed under these conditions.
ABSTRACT Herein, a series of novel cardanol polyoxyethylene ether sulfates (NESn, n = 3, 5, 7, 9) were synthesized via chlorosulfonic acid sulfation of commercial cardanol polyoxyethylene ethers (NSFn), and the effect of sulfation/sulfonation and EO number on solution properties was systematically studied. Compared with NSFn, sulfonation modification not only retains the advantages of nonionic surfactants but also endows the product with the characteristics of ionic surfactants. The introduction of anionic headgroup significantly enhances the water solubility by eliminating the cloud point. Meanwhile, NESn demonstrates excellent salt and alkali resistance. Specially, NES7 exhibits the highest alkali resistance (100 g/L NaOH), while NES7 and NES9 maintain stability even at 300 g/L NaCl or CaCl 2 . Increasing EO number raised the HLB value, γ cmc , and A min , while lowering cmc and Γ max due to the enhanced steric hindrance. Diffusion coefficients, both at short time and long time, decreased with EO length and concentration, indicating higher adsorption barriers, as verified by the smaller t *. Adsorption kinetics of NESn followed a mixed diffusion‐kinetic controlled adsorption mechanism. Small EO number decreases foaming but enhances foam stability. Emulsification favored NES3 for liquid paraffin and NES5 for soybean oil. This work provides key insights for designing green, high‐performance biomass‐based surfactants.
ABSTRACT Surfactant micelles are widely used to improve the aqueous solubility and delivery performance of poorly water‐soluble drugs. For micellar drug‐delivery systems, the extent of drug partitioning between the bulk aqueous phase and the micellar pseudo‐phase is a key determinant of solubility enhancement, drug retention, release behavior, and bioavailability. In this study, the micellar partitioning of three halogenated non‐steroidal anti‐inflammatory drugs (NSAIDs)—diclofenac (DFC), diflunisal (DFL), and flurbiprofen (FLP)—was investigated in nonionic polysorbate 20 (Tween 20; T20) micelles using semi‐equilibrium dialysis (SED) and differential absorbance spectroscopy. Both methodologies demonstrated that micellar partitioning followed the order FLP < DFL < DFC. Values of the solubilization constant, K C , were in the range of 68–360, with K C defined as where is the mole fraction of drug in micelles, is the molar concentration of free drug, and is the standard state concentration (. SED‐derived solubilization isotherms further showed that K C was not strictly constant but increased with increasing mole fraction of NSAID in the micelles, suggesting a synergistic solubilization effect, likely arising from favorable structural changes in the micellar environment as drug loading increases. Importantly, the partition coefficients obtained by differential absorbance were in good agreement with SED‐derived values at comparable micellar compositions, indicating that differential absorbance can provide a rapid and experimentally efficient estimate of NSAID partitioning in suitable surfactant systems.
ABSTRACT This study focuses on the development of a cost‐effective bioprocess for biosurfactant production, encompassing process optimization and physicochemical characterization. Surface tension reduction and oil dispersion activity were evaluated, highlighting its strong potential for applications in food, pharmaceuticals, and bioremediation. In this context, we evaluate the stability of the biosurfactant under extreme physicochemical conditions by measurement of the surface tension and oil dispersion activities. Overall, the lipopeptide biosurfactant derived from the NP11‐strain exhibited remarkable physicochemical stability under a wide range of pH from 2 to 10, salinity from 0% to 5% NaCl, and temperature from 4°C to 90°C. Having great interest, waste frying oil was valorized as a low‐cost carbon source for the economical production of the biosurfactant. A Plackett–Burman experimental design was applied to identify the most influential factors and determine their optimal levels for enhanced production. The optimized conditions were defined and validated based on key performance indicators, including maximal surface tension decrease, enhanced engine oil dispersion capacity, and increased biosurfactant yield. Significant variation in surface tension values was recorded with values ranging from 28.2 to 36.5 mN/m, corresponding to ST decrease values ranging from 59.71% to 47.85%.
ABSTRACT In this study, a novel cardanol‐based viscosity reducer was developed through learning from viscosity reducers derived from petroleum. Under the mechanism study through visual flooding experiment and computational fluid dynamics (CFD) simulation, the optimal petrochemical dodecyl dimethyl betaine (BS‐12) stood out, and oil recovery efficiency (EOR) could be as high as 30.7%. Based on the developed empirical formula and structural analysis of BS‐12, a completely new molecular structure was designed and applied in the visual flooding experiment, exhibiting comparable viscosity reduction performance and oil recovery efficiency.
ABSTRACT Conventional anionic surfactants generally exhibit poor salt tolerance and reduced interfacial activity under high‐salinity reservoir conditions, limiting their application in enhanced oil recovery (EOR). To address this issue, a series of anionic–nonionic isotridecanol poly(oxyethylene ether) sulfonate surfactants (ES‐n, n = 3, 6, 8, and 10) and their Gemini derivatives (GES‐n) were synthesized by introducing different numbers of ethylene oxide (EO) groups. The surfactants were characterized and evaluated through critical micelle concentration (CMC), dynamic interfacial tension, salt‐tolerance, contact‐angle, and oil‐washing tests. GES‐n exhibited superior interfacial activity compared with ES‐n due to the synergistic effects of dual hydrophobic chains and spacer‐induced structural constraints. Among them, GES‐06 showed the best overall performance, with a CMC of 1.29 × 10 −5 mol L −1 and an ultralow interfacial tension of 4.15 × 10 −3 mN m −1 at a salinity of 150 g L −1 NaCl. The water contact angle decreased from 113.1° to 22.4°, and the oil‐washing efficiency reached 78.26%, significantly higher than that of ES‐06 (42.18%). Appropriate EO regulation effectively balanced hydration and hydrophobic interactions, enhancing interfacial adsorption and oil recovery performance in high‐salinity reservoirs.
ABSTRACT This study aims to develop an efficient and controllable microchannel continuous‐flow synthesis process for dodecyl/tetradecyl dimethyl benzyl ammonium chloride (12/1427), verifying the feasibility of replacing conventional reactors with microchannel technology. A continuous flow synthesis system was constructed using a separation‐recombination type micro‐mixer, with dodecyl/tetradecyl dimethyl tertiary amine and benzyl chloride serving as the raw materials. The optimal reaction conditions were a temperature of 50°C, a flow rate of 5 mL min −1 , a molar ratio of 1:0.985, and a coil length of 3 m, the tertiary amine conversion reached 96.61%, the yield was 96.21%, the active substance content of the product was 45%, the free amine content was 1%, and the pH value of the 10% aqueous solution was 6.8. The critical micelle concentration (CMC) of the product was 0.98 g L −1 , and the corresponding surface tension (γ CMC ) was 33.62 mN m −1 . Its antistatic performance was comparable to that of industrial products. At a concentration of 50 ppm, both the microchannel product and the industrial product showed excellent bactericidal and bacteriostatic effects, with bactericidal and bacteriostatic rates exceeding 99.98%. The above results confirm that the microchannel continuous‐flow process is feasible for the production of 12/1427.
ABSTRACT Sustainable surfactants derived from renewable and low‐cost feedstocks are increasingly demanded to reduce environmental burden. Herein, waste human hair was valorized as a keratin source for the production of an oleoyl hydrolyzed keratin surfactant (OHKS). The keratin was first hydrolyzed under alkaline conditions to obtain a mixture of amino acids, which was then N‐acylated with oleoyl chloride to afford OHKS. FT‐IR and 1 H NMR provided evidence supporting amide bond formation and oleoyl incorporation. OHKS is a hydrolysate‐derived, compositionally distributed mixture rather than a single defined compound. As a hydrolysate‐derived mixture, OHKS still delivered surface activity comparable to sodium dodecyl sulfate and sodium lauryl sulfate, with a critical micelle concentration of 0.4 g·L −1 and a surface tension at CMC of 27.6 mN·m −1 , while exhibiting markedly improved mildness, with irritation indices of 1.42, 4.43, and 4.75 for OHKS, sodium dodecyl sulfate (SDS), and sodium lauryl sulfate (SLS), respectively. This study suggests a feasible and value‐adding route to convert keratin‐rich waste into a functional surfactant, highlighting the potential of waste protein valorization in advancing sustainable surfactant development and circular bioeconomy strategies.
Surfactant is the core active ingredient in personal cleaning products, which has potential irritation to skin and eyes. However, the mechanism of regulating the irritation of surfactants is still unknown. In this paper, we explored the effect and mechanism of adding co-surfactants on the irritation of the popular green surfactant potassium cocoyl glycine (PCG) system through the combination of experiment and molecular dynamics simulation. The results showed that the clusters formed by the combination of PCG and co-surfactants were larger and more stable, which led to fewer free monomers and a reduction in surfactant irritation. Additionally, the introduction of co-surfactants improved the foam performance of PCG systems, increasing both the maximum foam volume and the foam half-life. These results provide theoretical support and basic data for the development of cleaner products with lower irritation. Based on this, an amino acid facial cleansing product was developed and its performance and efficacy including cleaning ability and human safety testing were evaluated. The results showed that the cleaning product prepared by PCG and co-surfactants had not only excellent cleaning effects but also better moisturizing effects and soothing effects, which enable it to be safe and suitable for sensitive skin.
Biosurfactants from extremophilic bacteria are promising green alternatives to synthetic surfactants, particularly for industrial and environmental processes that demand stability under harsh physicochemical conditions. In this study, alkaliphilic bacterial strains were isolated from a high-pH mud volcano using Horikoshi I medium (pH 10-10.5) and evaluated for biosurfactant production in hydrocarbon-supplemented Bushnell Haas medium. A total of 24 isolates were subjected to multi-assay screening, including drop collapse, oil spreading, emulsification, and surface tension measurements. Drop collapse and oil spreading assays showed strong correlation with surface tension reduction, validating their reliability under alkaline conditions. Five isolates-Exiguobacterium alkaliphilum, Pseudomonas jilinensis, Pseudomonas sp., Pseudomonas fulva, and Alkalihalophilus pseudofirmus-demonstrated high activity, reducing surface tension to 26-30 mN/m, with the lowest value reaching 26.07 mN/m. To enhance comparability, a multi-dimensional visualization framework (heatmap, grouped bar plots, radar chart) was applied, enabling objective assessment across multiple performance parameters. This study presents the first systematic screening of biosurfactant-producing alkaliphilic bacteria from a mud volcano, establishing a reproducible workflow for extremophile evaluation. The results highlight microbial candidates with strong potential as resources for future environmental biotechnology, particularly for bioremediation and microbial enhanced oil recovery under alkaline conditions.
The use of microorganisms is an evolving method for the degradation of hydrocarbon contaminants. In this aim, halophilic hydrocarbon degrading bacteria were isolated from oil contaminated soil in Tunisia. A lipopeptide biosurfactant produced by Bacillus subtilis SPB1 was tested to increase diesel biodegradation along with co-inoculation with two BioS producing strains. Results revealed the enhancement of diesel biodegradation by the selected halophilic consortia when co-inoculating with B. subtilis SPB1 and the halophilic newly isolated strain (H1). The addition of the SPB1 lipopeptide seems not to have a pronounced effect on the biodegradation efficiency. However, the addition of an anionic surfactant SDS improves diesel digestion by 9.18%. Biostimulation with an organic nitrogen source improves greatly diesel biodegradation (25.24%). Results suggested the potential applicability of the selected consortia along with the in situ added BioS and biostimulation for the bioremediation of diesel contaminated water in marine environment.
Rapid-defoaming nonionic Gemini surfactants hold significant application value in processes such as industrial cleaning and photoresist development. In this study, three nonionic Gemini surfactants (B1, B2, and B3) with different polyoxyethylene (EO) chain lengths (n = 6, 7, and 8) were synthesized via a one-step method based on 2,5-di-tert-butylhydroquinone. The chemical structures of the resulting compounds were confirmed using Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy. The foaming behavior, surface tension, wettability, and emulsifying capacity were systematically evaluated. The findings revealed that foam stability for all surfactants remained below 35% and displayed a trend of initial increase followed by decrease as concentration rose, confirming their rapid defoaming characteristics. Under the same concentration, when increasing EO chain length, surface tension remained largely unchanged, while the wetting performance showed a decreasing trend. The emulsifying ability was improved with increasing concentration. This study systematically reveals the critical role of EO chain length in regulating the surface activity and foaming characteristics of nonionic surfactants, providing a theoretical basis for the development of high-efficiency surfactants.
ABSTRACT Biosurfactants are eco‐friendly, surface‐active compounds produced by microorganisms that have significant industrial and environmental applications due to their biodegradability and low toxicity. This study focuses on the production and characterization of biosurfactants by bacterial strain N19, a novel hydrocarbonoclastic bacterium isolated from Soummam River sediment. The bacterium was cultured in mineral salt medium supplemented with crude oil to stimulate biosurfactant production. Surface tension reduction (23.14 ± 0.12 mN/m), emulsification index (72.13% ± 1.15%), and oil displacement (4.2 ± 0.75 cm) tests confirmed the presence of an effective biosurfactant. Further phenotypic and molecular identification methods, including 16S rRNA sequencing, established the strain's identity as Rhodococcus ruber N19. This strain produced 7.92 ± 0.02 mg/mL biosurfactant. Structural characterization using thin layer chromatography (TLC), Fourier‐transform infrared (FTIR) spectroscopy, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF/MS), and liquid chromatography–tandem mass spectrometry (LC–MS/MS), and nuclear magnetic resonance (NMR) analyses revealed that the biosurfactant produced by this strain is a lipopeptide. The nonhemolytic properties, combined with the ability to lower surface tension and exhibit strong emulsification and oil displacement activities, highlight the potential of this biosurfactant for bioremediation, petroleum industry applications, and biomedical use.
ABSTRACT This study explores the synthesis of linear alkylbenzene sulfonate (LAS), a widely used surfactant, from pyrolysis oil derived from plastic waste, presenting an innovative approach to address sustainability challenges in surfactant production. Traditionally, LAS is synthesized from petrochemical feedstocks such as kerosene and benzene, but concerns over nonrenewable fossil resources and environmental impact have driven research toward alternative sources. The paper highlights pyrolysis, a thermochemical recycling method, to upcycle plastic waste into pyrolysis oil akin to synthetic crude oil. This pyrolysis oil serves as a feedstock for producing LAS, offering a pathway to reduce reliance on virgin fossil resources. The synthesis involved separating fractions via distillation, followed by alkylation and sulfonation reactions, to obtain LAS. Comparative analysis was conducted between the synthesized LAS and commercial LAS, focusing on surface activity, revealing similarity as well as some differences, likely due to impurities from pyrolysis and synthesis reactions. By showcasing the transformation of plastic waste into pyrolysis oil and subsequently into linear alkylbenzene sulfonate, this research exemplifies a practical application that could address the challenge of plastic waste management and demonstrates a sustainable pathway for producing a widely used surfactant, reducing dependence on virgin fossil resources.
ABSTRACT The sub‐region phase behaviors and percolation dynamics of the ionic microemulsion cetyltrimethylammonium bromide (CTAB)/1‐ethyl‐3‐methylimidazolium‐ethylsulfate (emim‐EtSO 4 )/oil (toluene + pentanol) were studied by dielectric spectroscopy. Two relaxations were observed at ~1 ns and ~60 ps, respectively. These two relaxations were identified as dipole polarization, although they are induced by different molecular groups. The concentration dependence of relaxation parameters on ionic liquids (IL), obtained by fitting Cole‐Cole equations to the dielectric data, was used to probe the microstructure and percolation behavior of the microemulsion. The critical concentrations C p and C 2 , which effectively determine the percolation dynamics, were obtained by analyzing the dependence of the conductivity and permittivity on IL concentration. The static percolation behavior of this system was verified by the scaling relationship between the conductivity and IL concentration. The microstructure of the oil‐IL interface in the bicontinuous phase has been inferred, which helps to reveal the essence of the percolation dynamics.
ABSTRACT Controllable DNA condensation is important for nucleic‐acid packaging and non‐viral gene‐delivery systems. This study aimed to determine how the composition of mixed nonionic C 12 E 10 and cationic gemini C 12 C 6 C 12 Br 2 surfactants regulates DNA condensation, structure, thermodynamics, and cytotoxicity. Calf thymus DNA was mixed with surfactant formulations containing different mole fractions of C 12 C 6 C 12 Br 2 . DNA–surfactant interactions were evaluated by UV spectroscopy, dynamic light scattering, ζ‐potential measurements, atomic force microscopy, differential scanning calorimetry, isothermal titration calorimetry (ITC), and cell‐viability assays. Increasing the gemini‐surfactant fraction induced a transition from extended DNA chains to compact globular complexes. Maximum condensation occurred at = 0.5, producing complexes of approximately 100 nm with positive ζ‐potentials. ITC showed that complex formation was spontaneous and predominantly entropy‐driven, consistent with counterion release, water reorganization, and hydrophobic association. At higher gemini fractions, overcharging and aggregate reorganization occurred. Incorporation of C 12 E 10 reduced cytotoxicity relative to the cationic C 12 C 6 C 12 Br 2 alone. These results demonstrate that mixed gemini/nonionic surfactant composition provides a controllable strategy for tuning DNA condensation and biocompatibility.
