Alcohol Polyoxyethylene Ether Sulfate Research Articles

Effects of residual foaming agent and defoamer on defoaming-flocculation-filterpress characteristics of earth pressure balance shield muck.

Foaming agents as a combination of several components are usually used as soil conditioning during earth pressure balance shield (EPBS) tunnelling. These residues in waste EPBS muck lead to a series of new challenges for in-situ recycling, i.e., foams overflow flocculation tank. This study investigates the effects of residual foaming agent components and defoamers on defoaming-flocculation-filterpress characteristics of EPBS muck using an improved flocculation and filterpress system. Residual foam height (Hf), defoaming ratio (DFR), antifoaming ratio (AFR), total suspended substance (TSS), turbidity, moisture content (MC), and zeta potential (ZP) were selected as characterization indices. The microstructure of filterpress cakes was analyzed using a scanning electron microscope. Results demonstrate that an enhancement within 0.0-1.0wt.% for sodium fatty alcohol polyoxyethylene ether sulfate (AES) and alpha olefin sulfonate (AOS) significantly reduces DFR and AFR. The MC and ZP decline, while the Hf and turbidity enhance. The combinations of nonionic surfactants alkyl polyglycoside (APG) and fatty alcohol-polyoxyethylene ether (AEO) in a concentration range of 0.0-1.0wt.% with 0.2wt.% AES causes the Hf, DFR, AFR, turbidity, and ZP to exhibit absolutely different variations. The MC with the growth in both APG and AEO presents a trend of first decreasing and then increasing. By increasing foam stabilizers sodium carboxymethyl cellulose (CMC) and guar gum (GG) within 0.02-0.10wt.%, the AFR, TSS, and ZP enhance in varying degrees, while the Hf, DFR, and MC gradually reduce. With the increase of defoamers hydroxyl silicone oil-glycerol polyoxypropylene ether (H-G) and dimethyl silicone oil-glycerol polyoxypropylene ether (D-G) within 0.002-0.010wt.%, the DFR and AFR are significantly improved, while the TSS, turbidity, MC, and ZP display varying degrees of reduction. Moreover, defoaming-flocculation-filterpress mechanisms of EPBS muck are explored to provide a useful reference for actual in-situ recycling projects.

Experimental study on improving salt resistance of dust suppressing foam with polymers

Mine dust is a prevalent pollutant generated during the mining process, often leading to explosion accidents and causing pneumoconiosis. Foam dust suppression technology has emerged as a promising method for efficient dust control due to its high-efficiency dust collection and ease of use. However, the application of foam in the field has revealed higher concentrations of inorganic salts in the mine dust suppressants, resulting in suboptimal foaming performance. As a result, additional foaming agent and increased concentration are often required to achieve the desired effect, which escalates the cost of mine dust control. To address this issue, this study proposes optimizing the performance of mine dust suppression foam through the incorporation of polymers with excellent salt resistance. In this investigation, foam liquids comprising xanthan gum (XG) and sodium carboxymethyl cellulose (CMC) were tested using FoamScan to evaluate their foaming performance and foam stabilization at various concentrations of inorganic salt. Additionally, the rheological properties of the foam liquids were analyzed by measuring the viscoelastic modulus using an interfacial rheometer. Experimental results demonstrated that the addition of XG and CMC did not compromise the foaming ability of sodium fatty alcohol polyoxyethylene ether sulfate (AES). Moreover, the liquid-carrying capacity of bubbles, in terms of foam stability, was enhanced. Specifically, the foam stabilization remained relatively stable when the XG concentration exceeded 0.5‰, even under different salt concentrations. Interfacial rheological tests revealed that the addition of XG substantially increased the viscoelastic modulus of the foam liquid. Furthermore, the phase angle remained below 45°, indicating the dominant role of the elastic modulus in the foam liquid, resulting in improved bubble resistance to interference and deformation. This experimental study successfully resolved the issue of poor stability in mine dust suppression foam caused by high salt content during the foam preparation process. The findings can significantly contribute to the widespread adoption and application of dust suppression foam technology in mining operations.

Synthesis and properties of ethoxylated vicinal diol nonionic surfactants with double hydrophilic head groups

A series of nonionic surfactants with double hydrophilic head groups was synthesized from ethoxylation of aliphatic 1,2-vicinal diols (C8, C10, and C12) with ethylene oxide, and characterized by Fourier transform infrared spectroscopy (FT-IR) and 1H nuclear magnetic resonance spectroscopy (1HNMR). Compared with linear primary alcohols, the lower residual alcohol content of the products indicates that the ethoxylation activity of the 1,2-vicinal diols was higher. The physicochemical properties and surface properties of the vicinal diol polyoxyethylene surfactant (DCjEn) were studied. The DCjEn surfactants reduced the pure water surface tension to ~ 30 mN m−1 with low critical micelle concentration variations of ~ 0.32–0.92 mmol L−1. The surfactant wettability was superior to that of typical commercial surfactant fatty alcohol polyoxyethylene ether (AEO9). A higher foamability and stronger foam stability that is comparable with that of widely used commodities, fatty alcohol polyoxyethylene ether sulfate (AES) and sodium dodecyl sulfate (SDS), were the remarkable properties of the DCjEn for a C12 alkyl chain length. With regards to functional properties, these novel nonionic surfactants can be used as primary surfactants in personal-care products.

Synergistic Effects between Anionic and Sulfobetaine Surfactants for Stabilization of Foams Tolerant to Crude Oil in Foam Flooding

AbstractIn foam flooding, foams stabilized by conventional surfactants are usually unstable in contacting with crude oil, which behaves as a strong defoaming agent. In this article, synergistic effects between different surfactants were utilized to improve foam stability against crude oil. Targeted to reservoir conditions of Daqing crude oil field, China (45 °C, salinity of 6778 mg L−1, pH = 8–9), foams stabilized by typical anionic surfactants fatty alcohol polyoxyethylene ether sulfate (AES) and sodium dodecyl sulfate (SDS) show low composite foam index (200–500 L s) and low oil tolerance index (0.1–0.2). However, the foam stability can be significantly improved by mixing the anionic surfactant with a sulfobetaine surfactant, which behaves as a foam stabilizer increasing the half‐life of foams, and those with longer alkyl chain behave better. As an example, by mixing AES and SDS with hexadecyl dimethyl hydroxypropyl sulfobetaine (C16HSB) at a molar fraction of 0.2 (referring to total surfactant, not including water), the maximum composite foaming index and oil tolerance index can be increased to 3000/5000 L s and 1.0/4.0, respectively, at a total concentration between 3 and 5 mM. The attractive interaction between the different surfactants in a mixed monolayer as reflected by the negative βs parameter is responsible for the enhancement of the foam stabilization, which resulted in lower interfacial tensions and therefore negative enter (E), spreading (S), and bridging (B) coefficients of the oil. The oil is then emulsified as tiny droplets dispersed in lamellae, giving very stable pseudoemulsion films inhibiting rupture of the bubble films. This made it possible to utilize typical conventional anionic surfactants as foaming agents in foam flooding.

Study on the influence of the external conditions and internal components on foam performance in gas recovery

In the lifting process of drainage gas recovery, external conditions and internal components of the foam are complex. We used molecular dynamics simulation to construct a series of fatty alcohol polyoxyethylene ether sulfate (AES) foam models that could represent various foams in different lifting stages from well to ground. The effect of temperature and pressure on foam stability was investigated. We found that there are two main reasons for foam instability in the first-half stage of the lifting process. Firstly, high temperature aggravated the molecule movement; some CH4 molecules entered the foam film and formed a molecular transport channel. Secondly, the interaction between the CH4 phase and condensate oil leads to some alkane molecules entering the gas–liquid interface. The calculation results and theoretical analysis will help to deepen the understanding of the performance of oily foams under harsh conditions.

Preparation and characterization of modified self-crosslinking fluorocarbon acrylate latex

The modified self-crosslinking fluorocarbon acrylate (MSFA) latex has been successfully synthesized via semi-continuous seeded emulsion polymerization. Methyl methylacrylate (MMA), butyl acrylate (BA), dodecafluoroheptyl methacrylate (DFMA), and hydroxypropyl methacrylate (HPMA) were chosen as main monomers, vinyl triethoxysilane (VTES), and benzyl methacrylate (BZMA) served as functional monomers. Latex was emulsified by mixed emulsifier containing nonionic surfactant alcohol ether glycoside (AEG1000) and anionic surfactant fatty alcohol polyoxyethylene ether sulfate (AES), and the reaction process was initiated by potassium persulfate (KPS). The optimal conditions were studied and obtained. The results indicated that the monomer conversion was up to 99.36%, and the coagulation was lowered to 0.60% under the optimal conditions. At the same time, the outward appearance of resultant latex presented blue white which confirmed the latex was a successful preparation. The latex was tested through Fourier-transform infrared spectroscopy (FTIR). The mechanical stability and chemical stability of latex were measured. Thermogravimeter (TGA) results demonstrated that the introduction of functional monomers has extensively augmented the thermal stability of prepared film. The glass transform temperature (Tg) was detected by differential scanning calorimetry (DSC) and the water resistance of film was evaluated through water contact angle (WCA). The average particle size of latex was 62.99 nm and PDI was 0.069.

Synthesis and Performances of Fatty Alcohol Polyoxyethylene Ether Sulfonate

Background: Fatty alcohol polyoxyethylene ether sulfonate (AESO) was synthesized by the following two steps reactions: fatty alcohol polyoxyethylene ether 5 (AEO-5) reacted with metallic sodium to form sodium alkoxide, then in toluene solvent, the sodium alkoxide reacted with 2-chloroethyl sulfonate sodium to form AESO. Methodology: The reaction factors, such as temperature, reaction time and reactant ratio, which effect on the product yield were discussed. The products were characterized by Fourier Transform Infrared (FTIR) spectra in order to examine the aim of the product synthesized. The AESO performances including thermal stability, salt resistance, emulsifying and surface properties were studied. Results: The results show that the optimum conditions of AESO synthesis are as follows: the reaction temperature is 64oC, the reaction time is 5h, the molar ratio of chloroethyl sulfonate sodium and sodium alkoxide is 1.2:1. In the above reaction conditions, the AESO has the highest yield, which is 74.43% and its purity is 89.25%. AESO’s surface properties, thermal stability, and salt resistance are much better than that of fatty alcohol polyoxyethylene ether sulfate (AES). The AESO presents the best emulsifying performance at the concentration of 1250mg/L. Conclusion: The solubility of AES and AESO are all increased due to the EO groups’ existence and their hard water resistances are better than that of lauryl sodium sulfate. The foamability test shows that AESO has the best foaming ability at the concentration of 1480mg/L, which decreases with the increase of the Ca2+ concentration, but the foam stability increases. It can be seen that AESO has favorable resistance to high temperature and high salinity.

Research on the influence of sodium fatty alcohol polyoxyethylene ether sulfate on the microstructure and properties of Portland cement

Sodium fatty alcohol polyoxyethylene ether sulfate (AES), an anionic surfactant, which relieves the contamination of Portland cement slurry containing mineral oil based mud (MOBM) effectively. In this paper, by testing fluidity and compressive strength firstly in 25 °C and 90 °C after 1, 3, 7, 14 and 28 days of curing respectively, Vipulanandan rheological model was applied to analyze rheological behavior. We found AES could deteriorate cement’s fluidity and compressive strength as its content increasing. Additionally, cement stone would lose about 85% of compressive strength as low as 0.05%wt AES especially. We observed microstructure of cement containing AES by Environment Scanning Electron Microscope (ESEM), which proved that AES causes cement surface to form holes, and the reduction of cement hydration products was confirmed by X-ray diffraction (XRD). Finally, by comprehensively analyzing combining Zeta Potential and Contact Angle, we used mathematical models to explain the mechanism of AES’s affecting on the structure and performance of cement: (1) In the slurry, AES deteriorates fluidity by trapping the free water. (2) AES attaches on cement particles surface, via affecting “Dynamic Potential” to decrease mutual repulsion between cement particles to accumulate them, resulting in uneven distribution of cement particles in the cement slurry with appearing holes and the dropping of density. (3) Foaming and its stability of AES makes structure of cement structure porous, forming entangled network structures and bounded air bubbles.

Synergy of surface-treated nanoparticle and anionic-nonionic surfactant on stabilization of natural gas foams

Positively charged surface-treated nanoparticle (S-AK) and anionic-nonionic surfactant sodium fatty alcohol polyoxyethylene ether sulfate (AES) mixture has been used to obtain natural gas foams. It was found that synergy occurs between S-AK and AES in generating stable natural gas foams due to the foam stability of the S-AK/AES mixture being better than that of either single component. It is important to control the contents of two species since there are optimum concentrations for S-AK and AES on stabilizing Natural gas foams. High salinity (≥50,000 mg L−1) is conducive to the stability of S-AK/AES natural gas foams at high temperature (50 °C). In addition to the electrostatic interaction, EO groups significantly promote the attraction between S-AK and AES. The stability of S-AK/AES natural gas foams may relate to two aspects: one is that AES-adsorbed nanoparticles migrate to the gas/liquid interface and enhance the interfacial dilatational elasticity, and the other is that a rigid skeleton structure forms in the natural gas foam films by the flocs consisting of S-AK and AES. Natural gas foams are most stable when the monolayer adsorption of AES molecules on the S-AK surface occurs in the dispersion.

Studies on the environmentally friendly deinking process employing biological enzymes and composite surfactant

In this study, biodegradable cardanol polyoxyethylene ether (CPE) was applied to the field of flotation deinking of mixed office waste paper (MOW), and its combination with fatty alcohol polyoxyethylene ether (AEO-9), fatty alcohol polyoxyethylene ether sulfate (AES) as a composite surfactant was also investigated for a green deinking process. The prepared composite surfactant was applied to the traditional alkaline chemical deinking. Moreover, the effect of cutinase on the deinking of MOW was also evaluated for the first time. Cutinases and amylases combined with the previously employed complicated surfactants were utilized to replace traditional chemicals for neutral deinking. The deinking effect and the environmental impact of these two deinking methods were evaluated in detail. The results showed that the surfactant composed of CPE/AEO-9/AES with a mass ratio of 1:1:1 can be used in traditional alkaline deinking, which could effectively improve the deinking pulp quality. Moreover, cutinase/amylase/surfactants deinking system could further enhance the deinking pulp quality. When pulped mixed office waste paper was treated with 0.2% of surfactants, 10 U g−1 of cutinase, 5 U g−1 of amylase at 50 °C for 30 min, the brightness of the deinked papers reached 92.24% ISO with an ink removal rate of 92.63%, tensile index of 24.83 N m g−1, and tear index of 9.48 mN m2 g−1. According to this study, cutinase and amylase combined with cardanol polyoxyethylene ether and other surfactants provide an environmentally friendly and effective deinking strategy.

Study on sodium fatty alcohol polyoxyethyleneether sulfate relieve the contamination of oil well cement with mineral oil-based drilling fluids

Contamination of oil well cement slurries with mineral oil-based drilling fluids (MOBM) is considered to be a great challenge for cementing security and quality. In this paper, a surfactant of sodium fatty alcohol polyoxyethyleneether sulfate (AES) relieve the contamination of oil well cement with MOBM was investigated. The cement slurries containing different MOBM and AES contents were prepared according to API Recommended Practice for testing oil well cements 10B-2 and rheological properties, compressive strength, porosity, gas permeability, Freeze-drying/Environment Scanning electron microscopy (ESEM), X-ray diffraction (XRD) were tested. The results indicate that the presence of MOBM in cement slurries resulted in a serious contamination (compressive strength and rheological properties decrease, porosity and gas permeability increase). On the other hand, above-mentioned properties increase with the addition of AES in contaminated cement slurries. The reason may be is that the added AES can damage the water-in-oil emulsification structure of contaminated cement slurries and improve the hydration of cement particles. In addition, this study provides a method to relieve the contamination and explores the mechanism of contamination to find the possibility of further measures.

Hyperbranched exopolysaccharide-enhanced foam properties of sodium fatty alcohol polyoxyethylene ether sulfate

The foam properties, such as the foamability, foam stability, drainage, coalescence and bulk rheology, of aqueous solutions containing an eco-friendly exopolysaccharide (EPS) secreted by a deep-sea mesophilic bacterium, Wangia profunda SM-A87, and an anionic surfactant, sodium fatty alcohol polyoxyethylene ether sulfate (AES), were studied. Both the foamability and foam stability of the EPS/AES solutions are considerably higher than those of single AES solutions, even at very low AES concentrations, although pure EPS solutions cannot foam. The improved foamability and foam stability arise from the formation of the EPS/AES complex via hydrogen bonds at the interfaces. The synergism between the EPS and AES decreases the surface tension, increases the interfacial elasticity and water-carrying capacity, and suppresses the coalescence and collapse of the foams. The EPS/AES foams are more salt-resistant than the AES foams. This work provides not only a new eco-friendly foam with great potential for use in enhanced oil recovery and health-care products but also useful guidance for designing other environmentally friendly foam systems that exhibit high performance.

Foam properties and stabilizing mechanism of sodium fatty alcohol polyoxyethylene ether sulfate-welan gum composite systems

Foam properties of the anionic–nonionic surfactant sodium fatty alcohol polyoxyethylene ether sulfate (AES) and microbial polysaccharide welan gum composite systems have been investigated. Both foaming ability and foam stability of AES/welan gum composite system are better than for either single component. It is important to control the quantities of the two species when to use, since there exist optimum foaming concentrations for AES (1000mgL−1) and welan gum (80mgL−1). Competitive adsorption exists between AES and welan gum at the air/liquid interface. A network structure is formed in the AES/welan gum composite system as the dynamic modulus has exponential relationship with the concentration. High interfacial elasticity is required to prevent the coalescence of the bubbles and the rupturing of interfacial layers. The hydrogen bonds and van der Waals forces between AES and welan gum may hinder AES molecules from diffusing from the bulk to the interface. The formation of an interface network of welan gum and the structural stability of double helices, arranged in parallel as zipper model within the network, strengthen the ability of the film to resist disturbance and deformation.