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Ethoxylation is one of the common industrial process in which ethylene oxide (EO) is added to compounds containing active hydrogen atom (OH, COOH, SH, NH, etc.) to form surfactants. Alcohol ethoxylates are a major class of non‐ionic surfactants composed of an alkyl chain combined with few EO units. They are widely used in homecare products, personal care products, textiles, oilfield, construction, lubricants, food, paper, leather. The analysis of these ethoxylates possess several challenges since they contain 'n' number of EO units (n > 1). With increase in "n," the product becomes more and more viscous and the boiling point increases making it difficult to analyze by normal gas chromatography (GC) technique. This paper describes a method of derivatizing these ethoxylates so that they can be eluted on a high temperature GC. BSTFA (N, O‐bis (trimethylsilyl) trifluoroacetamide) is used as the derivatizing agent (silylating agent). The ethoxylate combines with BSTFA to form the corresponding trimethylsilylated (TMS) product, which have comparatively lower boiling point. Thus, we detect trimethyl silyl product, which is the resemblance for the ethoxylated product. In this paper, we present a quantitative GC method for the ethoxylates of a few simple alcohols (2‐ethyl hexanol, glycerin), and complex vegetable oils (castor oil). The products formed during the reaction have also been identified on a gas chromatograph coupled with mass spectrometer (GCMS). GCMS shows the mass corresponding to the TMS derivatized product. The derivatization technique not only helps in increasing the volatility of these compounds but also improves the chromatographic efficiency, selectivity, and enhances the detectability. [ABSTRACT FROM AUTHOR]

Pharmaceutical, food, and cosmetic formulations often contain binary or ternary surfactant mixtures with synergistic interactions amongst micellar building blocks. Here, a ternary mixture of the surfactants hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, and sodium deoxycholate is examined to see if the molar fractions of the surfactants in the ternary mixed micellar pseudophase are determined by the interaction coefficients between various pairs of the surfactants or by their propensity to self-associate. Critical micelle concentrations (CMC) of the analyzed ternary mixtures are determined experimentally (spectrofluorimetrically using pyrene as the probe molecule). Thermodynamic parameters of ternary mixtures are calculated from CMC values using the Regular Solution protocol. The tendency for monocomponent surfactants to self-associate (lower value of CMC) determines the molar fractions of surfactant in the mixed micelle if there is no issue with the packing of the micelle building units of the ternary mixed micelle. If a more hydrophobic surfactant is incorporated into the mixed micelle, the system (an aqueous solution of surfactants) is then the most thermodynamically stabilized. [ABSTRACT FROM AUTHOR]

Textile is one of the biggest industries and it has an enormous impact on the global economy. However, the textile industry is labelled as the most polluting of all the industries and this is due to its contaminated wastewater. Textile wastewater contains organic hazardous compounds like alkylphenols (APs) such as nonylphenols (NPs), and alkylphenol ethoxylates (APEOs) for example nonylphenol ethoxylates (NPEOs), which may come from various detergents, wetting agents, emulsifying agents, etc. used in textile industries. Literature review revealed that no work was reported on the APs and APEOs in the textile wastewater of Bangladesh. This study reports the status of some APs and some APEOs after assessing wastewater of some textile industries in Dhaka, Bangladesh. Investigations were carried out with the wastewater of seven textile industries located in the Dhaka Division, Bangladesh. Tests were carried out by an Agilent Liquid Chromatography-Mass Spectrometer (LC-MS). The results revealed that none of the wastewater samples contained APs, and APEOs other than nonylphenol ethoxylates (NPEOs) a form of APEOs. And it might have released from the textile products treating stuff through dissolution process. Among all the seven industries, two industries (28%) contained nonylphenol ethoxylates (NPEOs). The mean concentrations of the detected NPEOs were determined as 11.27 ± 0.24 µg L-1 and 14.01 ± 0.09 µg L-1 in the wastewater of the mentioned two industries. The levels of the observed concentrations of NPEOs were much higher than the specified limits for textile wastewater. Findings of the present work will create pressure on the textile industries of home and abroad for treating textile wastewater effectively and not letting APEOs cum NPEOs in the wastewater. And such activities all over will pave the way to save the ecological system. [ABSTRACT FROM AUTHOR]

In this study, an optimized method was presented for the reverse quartz flotation in iron ore purification where sodium oleate (NaOL) was always selected as the collector due to its accessibility and economic benefits. Three alcohol ethoxylates, octylphenol ethoxylate (OP-10), nonylphenol ethoxylate (NP-10) and fatty alcohol ethoxylates (AEO-9) were introduced to improve the collecting performance of NaOL in the reverse flotation of quartz. It turned out that the addition of alcohol ethoxylates was helpful to increase the recovery of quartz in the flotation with the order of OP-10 > NP-10 > AEO-9. To characterize the adsorption of NaOL on activated quartz in different surfactant systems, Fourier-Transform Infrared Spectroscopy (FTIR) and Quartz Crystal Microbalance with Dissipation (QCM-D) were employed. Furthermore, the contact angles of the quartz surface that interacted with different surfactant systems were measured to investigate the synergy effect of NaOL and alcohol ethoxylates on the hydrophobicity of quartz. It turned out that alcohol ethoxylates promoted the adsorption of NaOL on the activated quartz, resulting in an increase in the hydrophobicity of quartz also in the order of OP-10 > NP-10 > AEO-9, which well explained the flotation results. Regular Solution Theory (RST) and the dilution effect based on the surface tension analysis were utilized to elucidate the synergy mechanism between NaOL and the alcohol ethoxylate. [ABSTRACT FROM AUTHOR]

The conditions that significantly affect the biodegradability of linear alkylbenzene sulfonate (LAS) based on previous studies were categorized. Among these previous studies, we focused on those that used activated sludge and river water as inocula in biodegradation studies. Analyzing the results of these studies revealed two types of methylene blue active substances (MBAS) removal curves in primary biodegradation, and the study conditions that differentiated the two types were analyzed, along with verification studies. The effects of the LAS concentration and interfacial activity during biodegradation were analyzed to set the concentration of LAS in this study. Surface tension was measured as an indicator of interfacial activity and biodegradation was measured by oxygen demand. Two widely used surfactants, alcohol ethoxylate and sodium dodecyl sulfate, were evaluated to clarify the significance of the effective concentration range of LAS. The concentration of LAS was set at 10 or 20 mg/L in the verification study. Acclimatization and the concentration balance of LAS and river water were the strongest factors in studies using activated sludge and river water, respectively. Our classification chart may be helpful in analyzing and comparing the conditions of previous and current studies. Such understanding of the study conditions and practical evaluation may aid in avoiding misleading environmental impact assessments of LAS. [ABSTRACT FROM AUTHOR]

In this paper a study for the selection of an NPE (nonylphenol ethoxylates)—free cocktail is discussed in order to be used for our routine liquid scintillation counting measurements. The NPE are added in the REACH (Registration, Evaluation, Authorization and Restriction of Chemicals)—list of amendments to Annex XIV, as chemicals which can't be used anymore (Commission Regulation (EU) 2017/999). Nine NPE-free cocktails were bought from different producers and investigated with respect to the homogeneity, background level and influence on counting efficiency for different radionuclides. Several sample matrices were considered for direct measurement of 3H and 14C. Based on this study we could select the best cocktail which fulfills our requirements for routine analyses. [ABSTRACT FROM AUTHOR]

To reduce the overdependence on petroleum‐based surfactants for the dyeing of polyester fabrics, a series of biodegradable cardanol‐based polyethoxylate oligomers (CPm, m = 5, 7 and 9) were synthesised by ethoxylation of cardanol with ethylene oxide. The synthesised compounds were characterised and confirmed by Fourier Transform–infrared spectroscopy and proton nuclear magnetic resonance spectroscopy. In addition, the physical, biodegradable and dyeing‐assisting properties of CPm were evaluated through comparison with tristyrylphenol ethoxylates (A typical commercial surfactant). Results revealed that CPm showed a higher hydroxyl value, better dispersing capability and a higher migration percentage than tristyrylphenol ethoxylates. Specifically, CP5 (0.5 g/L) improved the migration percentage by 12.03% compared with tristyrylphenol ethoxylates. The migration performance of the surfactants followed a descending order of CP5 > CP7 > CP9 > tristyrylphenol ethoxylates. Importantly, CP5 displays a higher degradation propensity than tristyrylphenol ethoxylates, demonstrating its biodegradable merit. In summary, the cardanol‐based polyethoxylates synthesised through this research are promising biodegradable and effective alternatives to conventional levelling agents for disperse dyeing, which contributes a new strategy to the sustainable development of the textile industry. [ABSTRACT FROM AUTHOR]

The study evaluated the co-metabolism of nonylphenol polyethoxylate (NPEO) within a main substrate stream subjected to biodegradation in an activated sludge system. Peptone mixture simulating sewage was selected as the synthetic substrate. As a novel approach, the NPEO concentration was magnified to match the COD level of the peptone mixture, so that co-metabolism could be evaluated by respirometry and modeling. A sequencing batch reactor (SBR) set-up at high sludge age to also allow nitrification was operated for this purpose. A long acclimation phase was necessary to start NPEO biodegradation, which was completed with 15% residual by-products. Modeling of respirometric data could identify COD fractions of NPEO with corresponding process kinetics for the first time, where the biodegradation of by-products could be interpreted numerically as a hydrolysis mechanism. Nonylphenol diethoxylate (NP2EO) was observed as the major by-product affecting the biodegradation of NPEO, because NPEO and NP2EO accounted for 60 to 70% of the total soluble COD in the solution during the course of biological reactions. The co-metabolism characteristics basically defined NPEO as a substrate, with no appreciable inhibitory action on the microbial culture both in terms of heterotrophic and autotrophic activities. [ABSTRACT FROM AUTHOR]

Poly- and perfluoroalkyl substances (PFAS) are a group of compounds with uses in industry and many consumer products. Concerns about the potential health effects of these compounds resulted in regulation by the Stockholm Convention on the use of three of the most common PFAS, including perfluorooctanoic acid (PFOA). Thousands of PFAS remain in production that are unregulated and for which their toxicity is unknown. Our group recently identified a new class of PFAS, fluorotelomer ethoxylates (FTEOs), in indoor dust and industrial wastewater. In this study, we investigated the effect of PFAS on placental metabolism by exposing healthy, pregnant CD-1 mice to PFOA or FTEOs at one of three concentrations (0 ng/L (controls), 5 ng/L, 100 ng/L) (n = 7–8/group). While PFOA is banned and PFOA concentrations in human blood are decreasing, we hypothesize that FTEOs will cause adverse pregnancy outcomes similar to PFOA, the compounds they were meant to replace. Placental tissue samples were collected at embryonic day 17.5 and 1H solid-state magic angle spinning nuclear magnetic resonance spectroscopy was used to determine the relative concentration of placental metabolites (n = 18–20/group). At the highest concentration, the relative concentrations of glucose and threonine were increased and the relative concentration of creatine was decreased in the PFOA-exposed placentas compared to controls (p < 0.05). In contrast, the relative concentrations of asparagine and lysine were decreased and the relative concentration of creatine was increased in the FTEOs-exposed placentas compared to controls (p < 0.05). Partial least squares - discriminant analysis showed the FTEOs-exposed and control groups were significantly separated (p < 0.005) and pathway analysis found four biochemical pathways were perturbed following PFOA exposure, while one pathway was altered following FTEOs exposure. Maternal exposure to PFOA and FTEOs had a significant impact on the placental metabolome, with the effect depending on the pollutant. This work motivates further studies to determine exposure levels and evaluate associations with adverse outcomes in human pregnancies. [Display omitted] • Fluorotelomer ethoxylates (FTEOs) were previously found to be environmentally persistent. • The health impacts of FTEOs are unknown. • Exposure of pregnant mice to FTEOs results in abnormal placental metabolism. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fast miniaturized extraction for analysis of 3 classes of pollutants in sediment. • US extraction with non-chlorinated solvent and extract clean-up performed in one step. • Cost-effective sample preparation and LC–FLD-DAD analysis. • Method meets the maximum permissible concentrations set by the Dutch RIVM. The study presents a simple and non-laborious method for the determination of 16 polycyclic aromatic hydrocarbons (PAHs), 2 phthalate esters (PEs), 2 alkylphenols (APs) and 4 alkylphenol ethoxylates (APEOs) in sediment. The method employs sample preparation combining focused ultrasound solid–liquid extraction (FUSLE) and in situ clean-up followed by liquid chromatography with fluorescence and ultraviolet detection. Extraction of 0.5 g sediment samples with 7 mL acetone in the presence of activated silica (0.5 g) and powdered copper (0.2 g) using an ultrasonic probe for 1 min resulted in recoveries of target analytes ≥ 78 %. The analytical method was classified as "acceptable green analysis" by the analytical Eco-Scale assessment (AESA) and scored 0.54 in the AGREEprep greenness assessment for sample preparation. Matrix-matched calibration was used to quantify analytes with a linear range for PAHs 2–1000 ng g–1, for PEs 100–5000 ng g–1 and for APs and APEOs 40–2000 ng g–1 dry weight. The reached limits of quantification (LOQ) for PAHs ranged from 1.1 to 3.1 ng g−1, for PEs from 122 to 124 ng g−1, for APs from 40 to 51 ng g−1 and for APEOs from 36 to 53 ng g−1. The applicability of the method was demonstrated by the analysis of real sediment samples and natural matrix certified reference material. [ABSTRACT FROM AUTHOR]

In the pipeline networks field, GAL surfactant can reduce drag forces relatively using a small quantity part per million (ppm). Accordingly, the drag reduction (DR) enhancement is highly recommended in many industrial applications specifically the crude oil transportation aspect. GAL solution was experimentally investigated at various concentrations. The experiments were performed at low concentrations range from 50 to 300 ppm, and high concentrations range from 1000 to 2000 ppm. The rotating disk apparatus (RDA) was used at various speeds range from 50 to 3000 rpm in all experiments. Torque values of the GAL solutions were compared with water alone. The results clearly show that the different concentrations of the Glycolic Acid Ethoxylate Lauryl Ether (GAL) are good drag reduction agents (DRAs), with clear and high torque reading differences. Further, GAL solutions have the same tendency at all concentrations. The torque finding was enhanced with increasing concentration. [ABSTRACT FROM AUTHOR]

In situ flushing through surfactant-enhanced aquifer remediation (SEAR) technology has long been recognized as a promising technique for NAPL removal from contaminated aquifers. However, there have been few studies on the choice of surfactants. In this work, the interaction quantitative model between resonance light scattering intensity and the concentration of binary surfactant mixtures NP-10+SDBS and NP-10+CTAB was established, and the mechanism of binary surfactant interaction was explored through the model by the resonance light scattering method. The relationship between the model constants and NAPL solubilization was also investigated to better address the application of surfactants in practical NAPL-contaminated site remediation. The critical micelle concentrations (CMCs) of nonylphenol ethoxylate (NP-10), dodecyl benzene sulfonate (SDBS), hexadecyl trimethyl ammonium bromide (CTAB), and the binary surfactant mixtures were measured by resonance light scattering (RLS), which were consistent with those obtained from surface tension measurements. In all cases, the RLS signals exhibited similar variations with surfactant concentration. A quantitative calculation model based on the RLS measurement data was established, and the binding constants KNP-10+SDBS and KNP-10+CTAB were calculated to be 0.66 and 1.51 L·mmol−1, respectively, according to the equilibrium equations. The results showed that the binding constants have a significant positive correlation with NAPL solubilization. [ABSTRACT FROM AUTHOR]

Electrooxidation (ELOX) of synthetic and real wastewater containing nonylphenol ethoxylate-10 (NP10E) surfactant as a model pollutant was investigated using a boron-doped diamond anode (BDD) in a continuous reactor in the presence of Na2SO4 or NaCl supporting electrolyte. Response surface methodology (RSM) with there factors and five coded levels (Central Composite Design, CCD) was used to optimise the continuous ELOX process performing 17 runs for each supporting electrolyte type. Individual and interactive effects of process variables such as initial pH of synthetic wastewater, current density and electrolysis time on NP10E electrooxidation were investigated in terms of COD, TOC, and NP10E removal efficiencies. It was found that NP10E to be more efficiently electrooxidized when NaCl was used as the supporting electrolyte. Under the optimal experimental conditions (initial pH 8, current density of 250 A/m2 and electrolysis time of 45 min) for electrooxidation of synthetic wastewater, the removal efficiencies were 91.6%, 94.3% and 85.3% with the operating cost of 0.90 US$/m3 for COD, TOC, and NP10E, respectively. In the studies conducted with real wastewater, obtained results were very close to these results. And also, kinetic studies were performed to find the reaction rate coefficient at the optimum conditions. Based on the type of supporting electrolyte the COD removal rates were fitted first order and zero-order reaction kinetic rules for Na2SO4 and NaCl, respectively. [ABSTRACT FROM AUTHOR]

The effect of ethylene oxide number (EON) polydispersity on the phase behavior of alkyl ethoxylates has been well documented in the surfactant literature. These previous studies show that polydisperse alkyl ethoxylates appear more hydrophilic as the surfactant concentration decreases or as the oil‐to‐water ratio increases. This becomes a troubling issue considering that most surfactant formulations undergo dilution during use, and they experience a wide range of water‐to‐oil volume ratios. Within the hydrophilic–lipophilic difference framework, the surfactant hydrophobicity is assessed via the sigma (σ) term (also known as the characteristic curvature or Cc). In this work, the effect of surfactant concentration on the apparent value of sigma (σapp) is evaluated as a function of surfactant concentration. The experimental observations are then explained using a bifunctional model for alkyl ethoxylates that consider the dual nature of polar oils (free alcohol and low EON ethoxymers) as surfactants and as oil components. A segregation‐based model and a partition‐based model are implemented to account for the distribution of the ethoxymers in the surfactant pseudophase and the oil phase. Combining these distribution models with the bifunctional model and a group contribution model for sigma, one can predict the σ term versus surfactant concentration for a given water/oil ratio, starting from the EON distribution of the surfactant. The practical applications of the model are discussed. [ABSTRACT FROM AUTHOR]

Nonylphenol ethoxylates (NPEOn), typically NPEO10, are the second popular nonionic surfactants that have been banned or restricted from use and production by Europe since 1990 due to their poor degradability and high genetic toxicity. The hypothesis of this work is that the nonylcyclohexanol ethoxylates (NCEOn) may possess similar interfacial properties but lower biotoxicity and better biodegradability compared with NPEOn according to their structures. To verify this and to find the optimal alternative of NPEO10, the interfacial properties of NCEOn were compared with the typical commercial ethoxylates nonionic surfactants, such as nonylphenol ethoxylated‐10 (NPEO10), alcohol ethoxylated‐9 (AEO9), secondary alcohol ethoxylated‐9 (SAE9), and isomeric alcohol ethoxylated‐9 (TO9). It is the NCEO7 that shows excellent emulsifying ability similar to that of NPEO10. NCEO11 performed stronger detergency than other assayed commercial nonionic surfactants. Additionally, NCEOn possessed lower biological toxicity to aquatic organisms. Hence, NCEOn could be considered as a green substitute for NPEOn in the assayed application fields. [ABSTRACT FROM AUTHOR]

The detection of nonylphenol ethoxylates (NPEOs) and 4-n-nonylphenol (NP) in abamectin pesticide formulations was conducted using high performance liquid chromatography-fluorescence method, and distribution characteristics of NPEOs and NP in 4 formulations: emulsifiable concentrate (EC), microemulsion (ME), emulsion in water (EW), suspension concentrate (SC) were analyzed. Solution migrations of NPEOs and NP from packing material (plastic) were detected by soaking the samples with methanol as an oil-based analog, and the sources of NPEOs and NP in pesticide formulations were analyzed. Results showed that the detection rate of NPEOs, NP, and both in the 4 formulations was 60.47%, 62.79%, 51.16%, respectively. The detection of NPEOs and NP in complexation agent was higher than that in a single agent. The mean and median value of NPEOs and NP in 4 formulations from high to low both were EC > EW > ME > SC. Among them, EC contained 6.83% of NPEOs and 8.41% of NP, both were the highest in the tested samples. Component of NPEOs was more than that of NP in EC, while both were used equally in EW. 2 h migrations of NPEOs and NP were 0.16-49.34 and 0.19-18.05 μg/cm², respectively, while the values after 30 days were 0.76-66.48 and 2.84-137.79 μg/cm², respectively. At the beginning of the experiment, migration of NPEOs was more stable than NP, but migration of the both were close at 15 d, which ranged from 46.64%-100.82% and 46.89%-102.03% of 30 d migrations. The highest contribution of NP from packing plastic was 2.568%, while it was 0.241% for NPEOs. 30 d contribution of NP was 1.66-107.51 times to that of NPEOs, and the contribution of NP from plastic bags was higher than that from plastic bottles. The results demonstrated that NP was used more often than NPEOs in the packing of pesticide, but additives during production was the main source of NPEOs and NP in pesticide. Keywords: abamectin; nonylphenol ethoxylates; nonylphenol; packing plastic; migration [ABSTRACT FROM AUTHOR]

Scaled representation of the water-poor confined hydrocarbon core regime (yellow) surrounded by a polar region (green), as it is present at surfactant concentrations above 60 wt%. • Phase diagrams of binary mixtures of water and C 8 EO 8 CH 2 COOH are established. • A remarkable phase diagram without lyotropic liquid crystalline phases is found. • Spherical micelles of similar size and shape persist at any concentration. • In the concentrated regime, micelles are interdigitated and form an "osmotic brush". The surfactant C 8 EO 8 CH 2 COOH (Akypo LF2) and its salts have a small hydrophobic and a significantly longer hydrophilic part. As a consequence, there must be a significant steric constraint, once these surfactant molecules form micelles. In addition, the partially charged headgroups should bring some additional fine-tuning via electrostatic interactions to this "essentially non-ionic" surfactant. Phase diagrams of binary mixtures of water and C 8 EO 8 CH 2 COOH are established over large concentration and temperature ranges, also at different pHs and in the presence of sodium and calcium ions. Surface tensions and osmotic pressures are measured to understand the systems. To evaluate the microstructures, also Dynamic Light Scattering and Small-Angle X-ray Scattering are performed. Apart from the formation of coacervates at very low surfactant concentrations, spherical micelles persist over the whole concentration and temperature range and do not change in size and shape. At very high surfactant concentrations, above 60% by weight, where the headgroups are no longer fully hydrated, the standard core-shell structure of micelles vanishes and highly stabilized aggregates of 8–26 octyl chains are suspended in interdigitated polyoxyethylene layers and form an "osmotic brush". When the acid is partially transformed to a sodium salt, the repulsion between the micelles increases, whereas bridging between micelles prevails, when the counterions are calcium cations. Remarkably, the negative charges of the headgroups are randomly distributed in the hydrophilic ethylene oxide shell. Altogether, a phase diagram without lyotropic liquid crystalline phases and an extreme shift of the cloud-point in temperature and composition is found, similar to the phase diagram of C 8 EO 8 OH already known in literature. The phase properties can be explained by the curvature and packing constraints together with the Lindemann rule applied to short hydrocarbon chains. [ABSTRACT FROM AUTHOR]

Phosphorylated surfactants having ethoxylate spacer arms are promising excipients for charge reversal self-emulsifying drug delivery systems (SEDDS). 1,2-Dipalmitoyl- sn - glycero -3-phosphatidic acid disodium salt (PA), 2-((2,3-bis(oleoyloxy)propyl)dimethylammonio)ethyl hydrogen phosphate (DOCP), nonylphenol monophosphate ester (PNPP), C12-15 alcohol 3 ethoxylate phosphate ester (PME) and polyoxyethylene (9) dioctanoyl glycerol pyrophosphate (DGPP) loaded SEDDS were developed and characterized. Zeta potential of SEDDS was measured before and after incubation with intestinal alkaline phosphatase (IAP). Phosphate release was monitored by incubation of SEDDS with isolated as well as cell-associated IAP. Primary amine content on the surface of SEDDS was determined in parallel. Cytotoxicity was evaluated on Caco-2 cells and in vitro hemolysis test was performed. Cellular uptake studies were performed by confocal scanning microscopy. SEDDS formulations exhibited a size in the range of 17 and 193 nm and a polydispersity index (PDI) ≤ 0.5. Charge reversal from negative to positive values could be achieved in case of PNPP and PME loaded SEDDS with a zeta potential changing from −13 mV to +9 mV and from −7 to +2 mV, respectively, within 6 h. Significant amounts of phosphate were released from PNPP and PME loaded SEDDS incubated with isolated IAP and from all formulations incubated with cell-associated IAP in accordance with an increase in primary amines on the surface of oily droplets. SEDDS exhibited a concentration and time-dependent cytotoxicity. PNPP and PME SEDDS displayed an increased cellular uptake. [ABSTRACT FROM AUTHOR]

Nonylphenol ethoxylate-n (NPnEO) is a nonionic surfactant, and can be degraded in chemical and biological ways for short-chain NPnEO with n ≤ 10. However, when n is >10, the degradation of NPEO in wastewater was seldom reported. In this study, the electrochemical oxidation of long-chain NP40EO at high saline wastewater was investigated. The main influencing factors such as current density, plate distance, initial pH, salt type, and salt concentration on electrochemical degradation of high saline NP40EO wastewater were evaluated. The chemical oxygen demand (COD) removal efficiency increased with the increase of current density and reached 73.4% at 45 mA/cm2 after 6 h electrolysis. Plate distance had no effect on the COD removal. As compared with sodium sulfate (Na2SO4), sodium chloride (NaCl) solution led to better COD removal. A high COD removal efficiency was obtained at lower initial pH value. A possible electrochemical degradation pathway of NP40EO was proposed. The energy consumption increased with increasing current density, plate distance, initial pH value, and decreasing NaCl concentration. Based on the energy consumption analysis, the optimal operating parameters were obtained at current density of 30 mA/cm2, plate distance of 2.0 cm, NaCl concentration of 0.50 M, and initial pH value of 3.0. This result indicated that electrochemical advanced oxidation process is a feasible way for the treatment of long-chain NP40EO wastewater at high saline conditions. [ABSTRACT FROM AUTHOR]

Nonylphenol, octylphenol, and nonylphenol ethoxylates are manmade compounds that are only discharged in the environment due to anthropogenic activities. The objectives of this study were to determine the current concentrations of these substances in the Canadian freshwater environment and to determine if past regulatory actions were beneficial to the environment. Freshwater samples (n = 241) were collected and analysed for 4-nonylphenols (NP), nonylphenol monoethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO), and octylphenols at 35 sites in Canada from 2014 to 2019 with individual compound concentrations ranging from 1.29 to 477.22 ng/L. In addition, 18–65% of the samples were reported to be under the laboratory detection limit, depending on the compound. Sampling sites were categorised into five groups based on the dominant activities present upstream in their watersheds: mixed use sites; municipal waste water treatment plant (MWWTP)-associated sites; textile mill-associated sites; urban; and reference sites. All four compounds in the study were detected more frequently in urban and MWWTP-associated sites than at other locations. Additionally, there is a statistically significant (p < 0.05) downward temporal trend in NP concentrations in Canadian surface waters from 2014 to 2019. There were no exceedances of the Canadian Water Quality Guideline of 1000 ng/L. [ABSTRACT FROM AUTHOR]

The surface characteristics of sub-bituminous coal have been determined in the presence of nonylphenol ethoxylate with 9 ethylene oxide groups (NP-9). The surface characterization techniques of zeta potential measurement, contact angle measurement, and surfactant adsorption have been used. Addition of NP-9 causes the zeta potential profiles to become less negative resulting from the surfactant molecules shielding the negative charge of the sub-bituminous coal. Changes in the sub-bituminous coal surface hydrophobicity are assessed using contact angle measurements. As the concentration of NP-9 gradually increases, the contact angle first increases and then decreases with the maximum contact angle at about critical micelle concentration (CMC) of NP-9. FTIR and XPS results show that oxygen functional groups on the low-rank coal surface were significantly covered by the NP-9, which indicates more hydrophobicity for the low-rank coal after adsorbing surfactant. The surfactant adsorption has been investigated as a function of concentration and temperature. The adsorption isotherms are well fitted by the Langmuir equation. The adsorption data are utilized to calculate thermodynamic parameters. The thermodynamic functions indicate that the whole adsorption process is exothermic, being driven by enthalpy-entropy synergically. [ABSTRACT FROM AUTHOR]

Alcohol ethoxylates (AE) are commonly used nonionic surfactants with widespread adoption in consumer and industrial applications. The toxicology profile of this general class of molecules has been extensively reported previously. This report serves to make accessible previously unpublished toxicological data from 59 toxicology studies on AE produced from branched and semilinear alcohols produced by ExxonMobil, with alcohol backbones ranging from C9 to C15. Information on acute oral toxicity, acute dermal toxicity, genetic toxicity, skin irritation, eye irritation, skin sensitization, and oral repeat‐dose toxicity are presented here. These data significantly enrich the database on the toxicity of branched AE and support that the degree of branching presents no unique toxicological hazards in relation to that of semilinear AE in this report, as well as in comparison with similar data published on a range of linear, semilinear, and branched AE. [ABSTRACT FROM AUTHOR]

In this work, multiple-wall carbon nanotubes (MWCNTs) were purified with an acid treatment and subsequently dispersed using commercial surfactants, such as amino trimethyl phosphonic acid and nonylphenol. Then, the as-synthetized and dispersed MWCNTs were evaluated as a catalytic material for the degradation of the industrial dyes: methylene blue (MB), methyl orange (MO), and rhodamine B (RhB). The structural characterization was performed by SEM, XRD, BET, TEM, Raman, FT-IR, and UV-vis. The SEM-EDS technique revealed the increase in the purity of MWCNTs after an acidic purification process. XRD confirmed the hexagonal structure of the MWCNTs. Also, the BET technique showed an increase in the specific surface area after the purification process. Raman and FT-IR spectroscopies illustrated the crystallinity and functionality of CNTs with carboxyl and carbonyl groups. The dispersed MWCNT shows better degradation values of MB, RhB, and MO compared to the synthesized MWCNTs. This performance was attrbuted to the surface area present between the walls. The functionalization of MWCNTs with NaBH4 improved the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

The long carbon chain monomer modified polyacrylate latex was successfully prepared by semi-continuous seeded emulsion polymerization. In this work, methyl methacrylate and butyl acrylate were used as main monomers; stearyl acrylate was used as functional monomer, which were emulsified with the novel mixed surfactants of disodium laureth sulfosuccinate (AEMES) and alkylphenol ethoxylates (OP-10) and initiated with 2,2′-azobis (2-methyl propion- amidine) dihydrochloride initiator. The structure of the resultant latex was characterized by Fourier transform infrared spectroscopy. The differential scanning calorimetry, thermogravimetric analysis and contact angle were used to test the properties of the latex film. The particle size of the latex was measured by the Zetatrac dynamic light scattering detector. Factors, which have an influence on the properties of the latex and its film, have been investigated in detail. Results show that the optimal condition of synthesizing the latex is as follows: the amount of emulsifiers is 4%; the mass ratio of AEMES to OP-10 is 3:1; the amount of initiator is 0.7%; the content of SA is 6%. [ABSTRACT FROM AUTHOR]

With the advent of global regulations for safer detergent and an emphasis on a shift toward more environmentally friendly formulations, the environmental profile of surfactant chemistries have moved to the forefront of product formulation and design. The two cornerstones of surfactant environmental profiles are the ability to biodegrade in the natural environment and the ecological hazard profile. The objectives of this article are to describe biodegradation and aquatic toxicity data for a series of branched oxo‐alcohol ethoxylate (AEO) surfactants; to apply the target lipid model (TLM) for deriving model‐based threshold hazard concentrations (HC5) of AEO; and, finally, to accurately determine aquatic classifications for AEO surfactants for use in regulatory classification frameworks. Biodegradation results indicate a high level of biodegradability of branched AEO, with C8–C13‐rich oxo‐alcohols with 1–20 mol of ethoxylate meeting the readily biodegradable criteria. Results from acute and chronic toxicity tests indicated comparable or lesser aquatic toxicity versus linear AEO structures previously reported in the literature. The TLM model, applied a priori, resulted in good agreement with acute toxicity data (RMSE = 0.49) and is comparable to the root mean square errors (RMSE) previously determined for other narcotic chemicals (RMSE = 0.46–0.57). Model errors for invertebrates and fish were smaller than those for algae, with the TLM systematically overpredicting acute and chronic classification of two of seven branched AEO. Furthermore, TLM‐predicted HC5 values were determined to be sufficiently conservative, with 100% of observed chronic data (N = 79) falling above the HC5 threshold values, providing a useful tool for the risk assessment of AEO. [ABSTRACT FROM AUTHOR]

• A series of bimetallic catalysts based Au-Cu supported over nanoceria were prepared. • A 80% yield to AECA6 was achieved in the oxidation reaction of AEO7 with H 2 O 2. • The formation of a AuCu alloy at a Cu/Au molar ratio of 0.11 on Au enhances the catalytic activity. • The catalyst can be recycled and reused for at least 10 consecutive runs without loss of activity. • Cu on Au favors the adsorption of AEO7, H 2 O 2 and OH− on the catalyst surface compared to pure Au. • Isolated Cu sites on the AuCu alloy appear as crucial for enhancing the catalytic activity. We describe in this work the preparation of a series of bimetallic Au-Cu catalysts supported over nanoceria for the direct oxidation of C 12 -C 14 -alcohol polyethyleneglycol ether with on average 7 ethyl oxide units (AEO7) to polyoxyethylene lauryl ether carboxylic acid (AECA6), using H 2 O 2 as an oxidant, under basic conditions. Different preparation methods have been used, including deposition-precipitation, incipient wetness impregnation and wet impregnation for engineering the interaction between Au, Cu and nanoceria. The structure of the bimetallic catalysts is discussed in detail on the basis of refined characterization by XRD, HR-TEM, STEM-EDX-SDD, XPS and ICP-AES. The formation of a AuCu alloy over nanoceria at a Cu/Au molar ratio of 0.11 on Au allows a significant enhancement of the catalytic activity, resulting in an AECA6 yield up to 80% with a selectivity of 90%. The catalyst can be recycled and reused for at least 10 consecutive runs without apparent loss of activity. Detailed DFT calculations on Au, Cu and Au-Cu model alloys reveal a positive role of Cu on Au by favoring the adsorption of AEO7, H 2 O 2 and OH− on the catalyst surface compared to pure Au, as well as by reducing the energy barrier for H 2 O 2 cleavage. Isolated Cu sites on the Au-Cu alloy appear as crucial for enhancing the catalytic properties for AEO7 oxidation. [ABSTRACT FROM AUTHOR]

Herein, the anti-corrosive action of two Ethoxylates nonionic surfactants, namely isodecyl alcohol ethoxylates (IAE) and nonylphenol ethoxylates (NPE) for reinforcing steel in 3.5 %NaCl saturated with Ca(OH) 2 solution was assessed. Electrochemical measurements, surface examination, quantum chemical calculations and Monte Carlo (MC) simulations were investigated. The potentiodynamic polarization studies inferred that the examined inhibitors act as anodic type inhibitors. The adsorption of IAE and NPE on reinforcing steel surface follows Langmuir isotherm which resulted in pronounced corrosion resistance with reduced corrosion rate. The inhibition effect of the surfactants on the reinforcing steel surface was confirmed by SEM and AFM results. The corrosion inhibition tendency for the investigated surfactants was evaluated by employing the quantum calculations. While the interaction energy among the surfactant molecules and the metal surface was evaluated using MC simulations. The surfactants were found to be parallelly adsorbed on the Fe (110) surface which maximizes their contact with the steel surface as predicted using MC simulations. The results of different techniques are further used to ascertain the corrosion mechanism and also the adsorption mode of inhibitors in details. The results of theoretical studies validate the experimental studies with superior inhibition efficiency of NPE greater than IAE. Image 1 • The Environmentally Safe Ethoxylates Nonionic Surfactants were evaluated to protect Reinforcing Steel. • The electrochemical and SEM/AFM techniques confirmed the reinforced steel protection. • Pronounced corrosion protection was achieved due to the surfactant adsorption on the metallic surface. • The adsorption of IAE and NPE on reinforced steel surface follow Langmuir adsorption isotherm. • The quantum chemical calculations and MD simulations validate the experimental results. [ABSTRACT FROM AUTHOR]

Nonadiabatic effects in the two lowest electronic states of the ethoxy radical, the 1 2A and 2 2A states, are considered, using multireference configuration interaction (MRCI) wave functions comprised of over 15×106 configuration state functions. The lowest point on the seam of conical intersection is located. Using this point as the origin, a quasidiabatic Hamiltonian suitable for use in a multimode vibronic coupling treatment of the coupled 1 2A and 2 2A electronic states is determined. The Hamiltonian includes all contributions from all internal coordinates through second order in displacements from the origin and is comprised of over 500 parameters. By using the average energy gradient, the energy difference gradients, and the derivative couplings, all of which are obtained at little additional cost once the requisite eigenstates are known, the second order Hamiltonian is determined from MRCI calculations at only 35 nuclear configurations. This is essentially the same number of points required to obtain the frequencies for the ground state equilibrium structure using centered differences of gradients. The diabatic Hamiltonian provides a good description of the seam space, the (Nint-2)-dimensional space of conical intersection points, continuously connected to the minimum energy crossing point, enabling, for the first time, an analysis of the changes in the branching plane induced by seam curvature in the full seam space. Comparing the diabatic representation and MRCI results we find a good agreement for the ground state equilibrium structure, Req(1 2A), as well as the ground state energy and vertical excitation energy. In good agreement with the available experimental data are the ground state equilibrium structure and the excitation energy to the A 2A state, predicted here to involve a cone state level. Agreement between the harmonic frequencies at Req(1 2A) computed from the MRCI wave function and from the diabatic Hamiltonian is excellent for all but the three lowest energy normal modes where significant deviations are observed indicating the need for selected cubic and/or quartic terms. For the low-lying vibrational levels, the diabatic representation can be used to partition the normal modes into two groups, those that involve inter(diabatic) state coupling and those that are spectators as far as nonadiabatic effects are concerned. The spin-orbit coupling interaction is determined using the Breit-Pauli approximation and its incorporation into the diabatic Hamiltonian is discussed. [ABSTRACT FROM AUTHOR]

Understanding and predicting cloud point phenomena is important for the formulation of nonionic surfactant systems, and the design of cloud‐phenomena‐associated separation processes. There have been several approaches to fit and predict the cloud point phenomena, in most cases using bulk thermodynamic approaches. In this work, we introduced the hydrophilic–lipophilic‐difference and net‐average‐curvature (HLD‐NAC) as an interfacial (curvature) approach to predict cloud point values at different surfactant concentrations (cloud point curve). The HLD‐NAC method could fully predict the cloud point of alkyl ethoxylate of pure surfactants, typically within 4 °C of the experimental values, using published HLD constants, and the molecular structure of the surfactants. For commercial (polydispersed) surfactants, the same level of accuracy can be achieved if the experimental cloud point at 1 wt.% is used to adjust the HLD values. One additional benefit of using the HLD framework is the ability to predict changes in the cloud point curve with the introduction of electrolytes. While other models can fit the experimental data within 1 °C, the greater uncertainty of the HLD‐NAC (~4 °C) is a reasonable compromise given the simplicity of the approach. [ABSTRACT FROM AUTHOR]

The aqueous self‐assembly behavior of two homologous series of poly(ethylene oxide) (PEO)‐containing nonionic surfactants based on a C10‐Guerbet hydrophobe is reported. The two families of surfactants, alkyl ethoxylates and alkyl alkoxylates, are commercially available from BASF under the trade name Lutensol® XP‐series and XL‐series, respectively. The latter incorporate propylene oxide (PO) units in the surfactant chain. Dye solubilization was used to determine the critical micellization concentration (CMC) of each surfactant at 22 and 50 °C. The PO‐containing alkyl alkoxylates displayed lower CMC values, which were also more sensitive to temperature. The Gibbs free energy, enthalpy, and entropy of micellization were computed from the CMC data and used to identify the contribution of each surfactant moiety (alkyl chain, PO unit, and PEO block) in controlling the CMC. The micellization properties are compared with compositionally similar surfactants with linear alkyl chains, yielding information about the effects of the Guerbet alkyl chain on micellization. Isothermal titration calorimetry was also used to characterize the CMC and enthalpy of micellization which generally compare well with the dye solubilization results. Cloud point data reveal nonmonotonic relationships for the Lutensol® surfactants with respect to composition, unlike linear alkyl chain surfactants. Finally, dilute solution viscosity measurements performed on some Lutensol® surfactants show a change in the slope, suggesting a structural change that tends to be more pronounced for surfactants with longer PEO blocks. The data presented herein enhance the understanding of surfactant structure–property relationships required for industrial formulation. [ABSTRACT FROM AUTHOR]

Surfactants such as alkylphenol polyethoxylates (APEOs) and nonylphenol ethoxylates (NPEOs) are commonly used worldwide, but the majority of these compounds, together with their metabolites, have been reported to induce severe biological toxicity. Here, we evaluated for the first time the cytotoxicity, genotoxicity and mitochondrial damage in Chinese hamster ovary (CHO-K1) cells caused by a novel non-ionic surfactant, vanillin ethoxylates (VAEOs), an alternative to APEOs. In parallel, the same in vitro bioassays were conducted on NPEOs along with their metabolic byproducts 4-nonylphenol (4-NP) and vanillin. The results showed that the cytotoxic potency order was NPEOs > 4-NP > VAEOs > vanillin using CCK-8 assays. Also, 4-NP showed potential direct DNA damage in SOS/umu tests, whereas NPEOs, VAEOs and vanillin showed no positive result with and without S9 addition. In addition, none of the test compounds showed obvious genotoxic effects with low olive tail moment value using comet assays. However, all test compounds were shown to cause mitochondrial impairment by increasing mitochondrial mass and decreasing mitochondrial membrane potential in a concentration-dependent manner. And further analysis of reactive oxygen species (ROS) and mitochondrial superoxide (MNSOD) measurement showed that mitochondrial impairment was induced by oxidative stress with intracellular ROS and MNSOD overproduction. It's worth noting that VAEOs and vanillin cause relative lower cytotoxic, genotoxic and mitochondrial damage effects than NPEOs and 4-NP, indicating that VAEOs have the potential to substitute NPEOs as suitable surfactants. Take together, this study elucidates the toxicity profiles of VAEOs and NPEOs relatively comprehensively, and further toxicity analyses are suggested in the population, community and ecosystem. Unlabelled Image [ABSTRACT FROM AUTHOR]

A series of eleven ethoxysubstituted chalcones (E1‐E11) were synthesized and investigated for their inhibitory potential towards human recombinant monoamine oxidase A and B (hMAO−A and hMAO−B, respectively) and acetylcholinesterase (AChE). IC50 values of 4.63 ± 0.15 and 0.053 ± 0.003 μM were obtained for MAO−A and MAO−B, respectively, by the most interesting compound (2E)‐1‐(4‐ethoxyphenyl)‐3‐(4‐fluorophenyl)prop‐2‐en‐1‐one (E7), and it was characterized by a high selectivity index (SI=87.4) for MAO−B. Inhibitions by E7 against MAO−A and MAO−B were recovered (75.9 and 74.5%, respectively) to near the levels of reversible references (77.1 and 77.4%, respectively). The inhibition modes of E7 for MAO−A and MAO−B were competitive with Ki values of 2.65 ± 0.064 and 0.011 ± 0.0011 μM, respectively. Compounds (2E)‐1‐(4‐ethoxyphenyl)‐3‐(4‐ethylphenyl) prop‐2‐en‐1‐one (E10) and (2E)‐1‐(4‐ethoxyphenyl)‐3‐[4‐(trifluoromethyl)phenyl]prop‐2‐en‐1‐one (E11) showed good inhibitions against AChE with IC50 values of 2.86 ± 0.041 and 3.23 ± 0.0073 μM, respectively. A combined molecular docking/MM‐GBSA approach was used that employed quantum mechanics (QM) partial charges; this technique revealed the molecular rationale behind the observed MAO−B selectivity for this molecular series. Taken together, these results indicate that E7 is a potent, selective and reversible competitive inhibitor of MAO−B with moderately potent AChE inhibitory activity that has potential as a multi‐targeting drug [ABSTRACT FROM AUTHOR]

Highlights • The GO model was constructed based on XPS and typical molecular formula (C 10 O 1 (OH) 1 (COOH) 0.5). • Experimental and theoretical results of interaction between NPEO 10 and GO were compared. • Ethylene oxide groups of NPEO 10 are located on the GO surface. Abstract Graphene oxide (GO) performs excellent adsorption property in removing organic pollutant out of the aqueous solution. GO adopted in this research was synthesized by using an improved Hummers approach. With the adoption of X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR) and X-ray photoelectron spectroscopy (XPS), the samples were characterized. The mechanism of removing nonylphenol ethoxylates (NPEO 10) in the wastewater by GO was investigated through XPS and molecular simulations. The GO model was constructed on the basis of XPS outcomes and typical molecular formula of GO (C 10 O 1 (OH) 1 (COOH) 0.5). The XPS results indicate that the GO surface is significantly within the coverage of NPEO 10. From MD simulations, it was shown that NPEO 10 molecules adsorbed at GO surface through oxygen-containing functional group, and the polar interactions between the ethoxylate group and oxygen-containing functional group on the GO surface were the primary factors during the process of adsorption. The negative interaction energy existing between NPEO 10 and GO model suggests that the GO-water-NPEO 10 system becomes more stable after adsorption. [ABSTRACT FROM AUTHOR]

In this work, low rank coal was used for the removal of nonylphenol ethoxylate with fifteen ethylene oxide groups (NPEO15) from aqueous solutions at different contact times, temperatures, and initial adsorbent concentrations. The adsorption isotherms showed good fit with the Langmuir equation. Maximum adsorption capacities calculated at 308, 318, and 328 K were 23.64, 29.41, and 35.71 mg g–1, respectively. The changes in the free energy of adsorption (ΔG°), enthalpy (ΔH°), and entropy (ΔS°) were calculated in order to predict the nature of adsorption. The results of the thermodynamic analysis indicated that a spontaneous process took place, driven synergistically by both enthalpy and entropy. The adsorption kinetics of NPEO15 were consistent with a pseudo-second order reaction model. XPS results showed that the oxygen functional groups on the low rank coal surface were significantly covered by NPEO15. Furthermore, while the content of C–C/C–H functional groups increased significantly, that of C–O functional groups decreased after absorption. These results clearly indicate that low rank coal is more hydrophobic and displays better floatability. [ABSTRACT FROM AUTHOR]

Acids in diesel bring great harm to storage devices, transportation facilities and engines. Acids in diesel were removed by tetramethylammonium hydroxid (TMAH)/ammonia under nonylphenol ethoxylate as demulsifier. The effect of process parameters on removing acids was reviewed, such as volume ratio of TMAH to ammonia, volume ratio of deacidification agents to diesel, demulsifier dosage, deacidification temperature and deacidification time. The results showed that the optimum deacidification process was that volume ratio of TMAH to ammonia was 10:1, volume ratio of deacidification agents to diesel was 0.7:1, demulsifier dosage was 0.15 mL, deacidification temperature was 293 K and deacidification time was 5 min. Under the optimum process, deacidification rate of reached 88.36%. The deacidification process effectively removed acids in diesel, had a little effect on other physicochemical properties of diesel, moreover, the color of treated diesel also was greatly improved. [ABSTRACT FROM AUTHOR]

Abstract The aims of this work were to characterize the sorption and evaluate the inhibitory effect of octylphenol ethoxylate Triton X-100 (OPEOTx) on methanogenic and denitrifying sludges. According to Langmuir isotherm, maximums OPEOTx sorption values on methanogenic and denitrifying sludges were 60.70 mg (gVSS)−1 and 87.47 mg (gVSS)−1 respectively. The specific removal rate of chemical oxygen demand (r COD) and the accumulated volume biogas (V BG) were used to evaluate the OPEOTx inhibitory effect on sludges. Experimental inhibition data were fitted to the models of non-competitive inhibition and modified Gompertz. Methanogenic sludges reached higher levels inhibition in the r COD and biogas production potential P max (84.0 and 88.5%) comparing with denitrifying sludges (24.3 and 21.9%). Furthermore, in all OPEOTx concentrations, carbohydrates-proteins quotient value of the extracellular polymeric substances for the denitrifying sludges remained below respect to the same quotient in methanogenic sludges. The above contributes in part to explain the greater sorption capacity of the denitrifying sludges by OPEOTx and their granules resistance to be damaged by OPEOTx amphiphilic nature. The study gives insights to understand OPEOs interactions and their effects on methanogenic and denitrifying granular sludges. Graphical abstract Image 1 Highlights • Triton X-100 sorption on sludges was characterized by Langmuir and Freundlich isotherms. • A high methane production potential inhibition was occasioned by Triton X-100. • Triton X-100 led to a low inhibition in denitrifying sludge biological activity. • EPS carbohydrates content on sludges were not affected by Triton X-100. • Triton X-100 led to high EPS proteins solubilization on methanogenic sludges. [ABSTRACT FROM AUTHOR]

Nonylphenol ethoxylated (NPEOs) nonionic surfactants have been increasingly used in different industrial. commercial and domestic applications. Unfortunately, they are classified as endocrine disrupting chemicals (and also considered as contaminants of emerging concern) having adverse effects on animal and human reproduction. The treatment of nonylphenol-decaethoxylated (NP-10) via H2O2/UV-C process at different reaction times (5,10, 20, 40, 80min) and H2O2 concentrations was investigated. After 80 min treatment the removal rates of NP-10 solution (initial concentration 100 mg/L) in deionized water were 88%, 97% and 98% for 10,20 and 100mg/Lof H2O2 respectively. The same experimental conditions were applied to real wastewater spiked with 100 mg/L of NP-10 showing the following removal rates: 84%, 98% and 99%, respectively. The possible contribution of different radicals to NP-10 degradation by H2O2/UV-C treatment was investigated by evaluating the effect of different radical scavengers (namely NO2-, NaCI, Na2SO4, Na2CO3, KH2PO4 and phatalate). Toxicity data (Aliivibrio fischeri, Raphidocelis subcapitata and Daphnia magna) on treated solutions and wastewater highlighted the presence of residual toxicity in all samples evidencing that no complete mineralization occurred. [ABSTRACT FROM AUTHOR]

Nonylphenol (NP) is a stable metabolic product of nonylphenol ethoxylates, which is widely used as an industrial surfactant. NP has been classified as an endocrine disrupter, and its toxicity to organisms can be biomagnified through the food chain. As compared with the endocrine disrupting effect, the toxicity of NP to organisms has not been studied intensively, and the toxicity mechanisms have often been ignored. In the present study. Microcystis aeruginosa, a freshwater alga belonging to the first level of the trophic chain, was chosen to detect the toxicity of NP. The mechanisms of toxicity mediated by the AsA-GSH cycle were explored. The acute toxicity of NP to M. aeruginosa within 96 h was studied and an EC50 concentration of 3.45 mg/L was found. Further, the results showed that the toxicity of NP increased with the increase in concentration and exposure time. As compared with that in the control, the APX and MDHAR activities mostly increased. whereas DHAR activity fluctuated. However, the AsA content elevated at first, but decreased significantly after 72 h. For the GSH system. GR activity was always higher than that in the control. Nevertheless, the reduced GSH content was mostly inhibited. Therefore, the performance of AsA-GSH antioxidant defense system could explain the results of NP toxicity: the enzyme activities and antioxidant molecules increased initially, but an overall decline appeared after exposure for24 h. This research is helpful for estimating the toxicity of NP integrally and improves people's understanding of mechanisms of NP toxicity in algae. [ABSTRACT FROM AUTHOR]

A fast methodology to quantify 4-tert-octylphenol (4-t-OP) and 4-nonylphenol (4-NP) and their mono- and di-ethoxylates was developed, validated, and applied to real wastewater samples. Dispersive liquid-liquid microextraction was employed as a sample preparation step, leading to a pre-concentration factor of roughly 30. Analysis was carried out by liquid chromatography-tandem mass spectrometry with electrospray ionisation in multiple reaction monitoring mode. Average recoveries were generally between 80 and 120% for both the alkylphenols and their mono- and di-ethoxylates in influent and effluent wastewater. A minimum of 5 concentration levels per compound, ranging between 1 and 500 ng/mL, were prepared to construct calibration curves making use of isotopically labelled internal standards. The method presented good linearity and repeatability over the whole range of concentrations. Taking into account the concentration factor, and the recovery of the compounds, lower limits of quantification obtained in effluent wastewater were 0.04 ng/mL for 4-t-OP and 0.14 ng/mL for 4-NP, complying with European regulations, and between 0.03 ng/mL and 0.39 ng/mL for the ethoxylates. In influent wastewater, these limits were slightly higher. The total run time of 5 min for the alkylphenols and 8 min for the ethoxylates ensured high throughput. The developed method was applied to determine 4-t-OP and 4-NP and their mono- and di-ethoxylates in wastewater from several tank truck cleaning companies, which was subjected to ozonation and/or biological treatment. It was demonstrated that ozonation was best applied after the biological treatment, since in this case, the biological treatment could degrade most of the biodegradable organic matter, after which ozone could react directly with the recalcitrant organic pollutants. In this case, the concentrations of the target compounds in the wastewater of the investigated company decreased below the legally allowed concentration of the European water legislation. [ABSTRACT FROM AUTHOR]

In this study, the sol-gel method was used to prepare Mgdoped TiO2 nanoparticles from titanium tetraisopropoxide and magnesium sulfate as the dopant precursors. Mg-doped TiO2 shows the formation of anatase phase with polyhedral and spherical particles with an average size of 25-30 nm. X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and photoluminescence were used to characterize the prepared material. The photocatalytic degradation performance of rhodamine B, nonylphenol ethoxylates, pseudoephedrine hydrochloride, and nicotine on Mg-doped TiO2 was studied under UV irradiation. The photocatalytic degradation shows that 98.92, 98.00, 98.00 and 97.95% of rhodamine B, nonylphenol ethoxylates, pseudoephedrine hydrochloride, and nicotine was decomposed by Mg-doped TiO2, respectively. [ABSTRACT FROM AUTHOR]

Castor oil acid methyl ester ethoxylate sulfonate (CAMEES) is a new multifunctional anionic-nonionic surfactant with three hydrophilic groups. In this work, CAMEES was synthesized through reaction of castor oil acid methyl ester ethoxylate (CAMEE) with sodium bisulfite in the presence of tert-butyl peroxybenzoate as catalyst and ferric chloride as co-catalyst in solution of water and isopropanol. The sulfonic acid group has an important effect on the physicochemical properties of the surfactant. Compared to CAMEE, CAMEES exhibits better soybean oil emulsification, detergency, foam ability and stability. However, owing to the sulfonic acid group, the wetting ability and paraffin emulsification are more limited. [ABSTRACT FROM AUTHOR]

Abstract An environment-friendly liquid phase exfoliation method assisted with alkyl ethoxylate wetting agent has been developed to prepare highly concentrated hexagonal boron nitride nanosheet (BNNS) colloidal suspensions with loadings of up to ~ 36.3 mg/mL. The exfoliation yield reaches ~78.3%. BNNS as thin as ~0.7–11.3 nm has been obtained and it retains pristine in-plane crystal structure without chemical bonds to alkyl ethoxylate. The obtained BNNS has been successfully applied to oxide/oxide ceramic composites (SiO 2f /SiO 2) as an interphase layer between fiber and matrix. The composites with BNNS generally exhibit non-catastrophic failure behaviour with the flexural strength of ~ 40–50 MPa and fracture toughness of ~ 1.68 MPa m1/2 which is about 50% higher than that of the composites without BNNS interphase. The effect of the BNNS interphase thickness on the mechanical properties of the composites has been studied and the role of BNNS in the toughness enhancement has been discussed. Furthermore, thermal stability of the BNNS interphase against prolonged heat treatment has been examined. Our alkyl ethoxylate assisted liquid phase exfoliation method paves a way for the applications of BNNS in various electronic or optical devices and also for the synthesis of nanocomposites. [ABSTRACT FROM AUTHOR]

Tristyrylphenol ethoxylates (TSPxEOs), nonionic surfactant adjuvants, are widely used to replace alkylphenols in many agricultural formulations. Herein, a rapid and sensitive method based on a modified quick, easy, cheap, effective, rugged, and safe “QuEChERS” and supercritical fluid chromatography–tandem mass spectrometry (SFC–MS/MS) method was developed to quantify TSPxEOs in cucumber, leaves, and soil. Following optimization, the tested oligomers were fully separated within 8 min. The matrix-matched calibration standards showed satisfactory linearity with coefficients of determination ( R 2 ) ≥ 0.991. The limits of quantification (LOQs: 0.001–0.048 μg kg −1 ) were excellent for TSPxEOs (x = 6–29). The average recoveries at three (low, medium, and high) fortification levels were ranged between 62.5% and 112.9% with relative standard deviations (RSDs) ≤20.0% for TSPxEOs (x = 6–29) in various matrices. The method was successfully applied to determine TSPxEOs residual levels in field-incurred samples. Conclusively, the developed method is versatile and could be used for monitoring TSPxEOs in food and environmental samples. [ABSTRACT FROM AUTHOR]

In this study, the microbial community characterization and metabolic pathway identification involved in the linear alkylbenzene sulfonated (LAS) degradation from commercial laundry wastewater in a fluidized bed reactor (FBR) on an increased scale were performed using the Illumina MiSeq platform. Ethanol and non-ionic surfactant (LAE, Genapol C-100) were used as co-substrates. The FBR was operated in five operational phases: (I) synthetic substrate for inoculation; (II) 7.9 ± 4.7 mg/L LAS and 11.7 ± 6.9 mg/L LAE; (III) 19.4 ± 12.9 mg/L LAS, 19.6 ± 9.2 mg/L LAE and 205 mg/L ethanol; (IV) 25.9 ± 11 mg/L LAS, 19.5 ± 9.1 mg/L LAE and 205 mg/L ethanol and (V) 43.9 ± 18 mg/L LAS, 25 ± 9.8 mg/L LAE and 205 mg/L ethanol. At all operation phases, organic matter was removed from 40.4 to 85.1% and LAS removal was from 24.7 to 56%. Sulfate-reducing bacteria (SRB) were identified in the biofilm of FBR in all operational phases. Although the LAS promoted a toxic effect on the microbiota, this effect can be reduced when using biodegradable co-substrates, such as ethanol and LAE, which was observed in Phase IV. In this phase, there was a greater microbial diversity (Shannon index) and higher microorganism richness (Chao 1 index), both for the Domain Bacteria, and for the Domain Archaea. [ABSTRACT FROM AUTHOR]

Abstract Nonylphenol polyethoxylate (NPnEO) surfactants, ubiquitous contaminants in sewage processing facilities, continue to receive attention due to their recalcitrance and diverse toxicity concerns. How the addition of nonylphenol diethoxylate (NP2EO) and its biodegradation products affect microbial community structure in anaerobic semi-continuous digesters was investigated by molecular techniques. Fluorescence in situ hybridization (FISH) and quantitative PCR (qPCR) were used in parallel to monitor total Bacteria, four classes of Proteobacteria, total Archaea, and two genera of acetoclastic methanogens (Methanosarcina and Methanosaeta). Beta- and Gammaproteobacteria were the dominant phyla and the relative abundances of both groups were roughly doubled following NP2EO addition. While Methanosaeta was dominant over Methanosarcina throughout, NP2EO addition and accumulation of NP nearly doubled the relative abundance of Methanosarcina. While digester performance was not affected, this study revealed that relative abundances of the key players in anaerobic digestion were altered by the addition of NP2EO. Graphical abstract Image 1 Highlights • 90% of nonylphenol diethoxylate was degraded in 52 days in anaerobic digesters. • Relative abundances of Beta- and Gammaproteobacteria doubled in spiked digesters. • Methanosaeta was the dominant acetoclastic methanogen in all operated digesters. • The relative abundance of Methanosarcina nearly doubled in spiked digesters. • Addition of NP2EO led to changes in microbial community composition. [ABSTRACT FROM AUTHOR]

Cloud point extraction has been shown to be an effective technique to remove hydrophobic volatile organic compounds (HVOCs) from aqueous solution using nonionic surfactant. A cocurrent vacuum stripper is used to recover the surfactant in coacervate phase from extraction for economic viability. The solutions containing two series of aromatic and chlorinated HVOCs. Surfactants studied were alkyl phenol ethoxylates, secondary alcohol ethoxylates (AEs), and branched secondary AEs. From equilibrium measurements, the apparent Henry’s law constant (volatility) of the HVOCs in surfactant solution decreased with increasing HVOCs hydrophobicity due to solubilization of the HVOCs in micelles. The results showed that the mass transfer of HVOC decreases due to the solubilization enhancement of the HVOCs. [ABSTRACT FROM AUTHOR]

Abstract The analysis of nonylphenol (NP) and its precursor nonylphenol ethoxylates (NPEOs) in food and environment is an increasing concern from the viewpoint of risk assessment due to their endocrine-disrupting effects. This review provided an updated overview of recent advances in the analysis of mixtures of NPEO homologues and their degradation product NP in food and environment published since 2013. The miniaturized and automated sample preparation techniques, as exemplified by magnetic solid-phase extraction and liquid phase microextraction have become the promising technologies for analysis the targets. Gas and liquid chromatography coupled to mass spectrometers are still predominant technologies for analysis of the targets, but the supercritical fluid chromatography coupled to tandem mass spectrometer that has emerged recently may become an alternative method. Due to the need for in-depth study of the isomer-specific toxicity, the analysis of NPEO homologues and their degradation product NP isomers individually will be also highlighted in future. Highlights • Recent advances in analysis of NPEOs and their degradation product NP were listed. • Sample-preparation methods for analysis of NPEOs and NP in foods and environment. • Determination methods for NPEOs and NP at low levels. • Future trends in the analysis of NPEOs and NP in foods and environment. [ABSTRACT FROM AUTHOR]

The cloud points tcp of aqueous solutions of ethoxylated monoalkylphenols, AF9-n (n = 8,9,10,12), were measured in the concentration (C) range of 0.25-40 wt.%. tcp increased as C decreased at C < 1 wt.%. At 1 < С < 10 wt.%, tcp changed insignificantly; Δtcp/tcp did not exceed 5%. Solutions transformed into the gel state at С > 10-20 wt.% and tcp sharply increased. The dependence of tcp on the length of the oxyethylene chains of ethoxylated nonylphenols at C = 1 wt.% can be described by the equation tcp = b·ln(n-n0), where n0 = 6. The cloud points of aqueous solutions (C = 1 wt.%) of the ethoxylated nonylphenols were measured at different concentrations of NaI, NaCl, NaF, Na2CO3, and Na2SO4 salts. For all of these solutions, tcp decreased in the presence of NaCl, NaF, Na2CO3, Na2SO4 and increased in the presence of NaI. To describe the dependence of tcp on the salt concentration, the equation was suggested, where and tcp are the cloud points of a neat aqueous solution of ethoxylated nonylphenols and of the solution in the presence of electrolytes, respectively. [ABSTRACT FROM AUTHOR]