Alcohol Ethoxylate Surfactants Research Articles

Emerging pollutants in textile wastewater: an ecotoxicological assessment focusing on surfactants.

Water and several chemicals, including dyestuffs, surfactants, acids, and salts, are required during textile dyeing processes. Surfactants are harmful to the aquatic environment and induce several negative biological effects in exposed biota. In this context, the present study aimed to assess acute effects of five surfactants, comprising anionic and nonionic classes, and other auxiliary products used in fiber dyeing processes to aquatic organisms Vibrio fischeri (bacteria) and Daphnia similis (cladocerans). The toxicities of binary surfactant mixtures containing the anionic surfactant dodecylbenzene sulfonate + nonionic fatty alcohol ethoxylate and dodecylbenzene sulfonate + nonionic alkylene oxide were also evaluated. Nonionic surfactants were more toxic than anionic compounds for both organisms. Acute nonionic toxicity ranged from 1.3mg/L (fatty alcohol ethoxylate surfactant) to 2.6mg/L (ethoxylate surfactant) for V. fischeri and from 1.9mg/L (alkylene oxide surfactant) to 12.5mg/L (alkyl aryl ethoxylated and aromatic sulfonate surfactant) for D. similis, while the anionic dodecylbenzene sulfonate EC50s were determined as 66.2mg/L and 19.7mg/L, respectively. Both mixtures were very toxic for the exposed organisms: the EC50 average in the anionic + fatty alcohol ethoxylate mixture was of 1.0mg/L ± 0.11 for V. fischeri and 4.09mg/L ± 0.69 for D. similis. While the anionic + alkylene oxide mixture, EC50 of 3.34mg/L for D. similis and 3.60mg/L for V. fischeri. These toxicity data suggested that the concentration addition was the best model to explain the action that is more likely to occur for mixture for the dodecylbenzene sulfonate and alkylene oxide mixtures in both organisms. Our findings also suggest that textile wastewater surfactants may interact and produce different responses in aquatic organisms, such as synergism and antagonism. Ecotoxicological assays provide relevant information concerning hazardous pollutants, which may then be adequately treated and suitably managed to reduce toxic loads, associated to suitable management plans.

Dynamic salinity‐induced phase‐inversion conductivity measurements used to characterize alcohol ethoxylate based surfactant/oil/water systems

AbstractDynamic conductivity measurements proved to be an effective and rapid method to determine the optimal experimental conditions for a salinity‐induced phase‐inversion from surfactant/oil/water (SOW) systems consisting of nonionic surfactants, more specifically alcohol ethoxylates. This emerging methodology can be used as a rapid screening tool to determine the impact of alcohol ethoxylate surfactants in a SOW solution and was demonstrated to be not only repeatable, but highly comparable to the traditional static method, in which the solutions are added to flat bottom tubes and allowed to equilibrate at a given temperature for extended time periods. Given a set of experimental conditions (oil‐type, temperature, etc.), these dynamic salinity‐induced phase‐inversion (Dy‐SPI) conductivity measurements can be used to determine the optimal salinity (S*) for a given surfactant at a set concentration, as well as its characteristic curvature via a series of experiments with varying oil types. Additionally, Dy‐SPI was used to confirm the previously observed inverse relationship between the concentration of an alcohol ethoxylate and S* under a given set of conditions. What makes this method so unique is the amount of time (30 min to 1 h) and the simplicity of the equipment needed for these Dy‐SPI conductivity measurements, allowing for a rapid screening tool for these SOW parameters.

A simple method for predicting alkane‐water partition coefficients of surfactants

AbstractAlkane/water (logPalk) partitioning systems are gaining relevance in applied surfactant science but there is still a challenge to calculate logPalk values for surfactants. In this contribution, a simple method of calculating logPalk at sub‐micellar concentrations for a wide range of nonionic surfactants is presented, using a linear combination of octanol/water partition and hydrogen‐bonding contribution parameters of surfactants. These two parameters can be easily calculated using many commercial or open‐access software packages. The model requires a critical folding chain length factor to account for entropic effects arising from conformational behavior of the ethylene‐oxide chain for alcohol ethoxylate surfactants. This observation is substantiated by conducting a conformational lipophilicity study by molecular dynamics simulations of two alkylphenol ethoxylates as model surfactants. Polydispersity is not seen as a major factor in calculating the logPalk of surfactants. The model is shown to outperform previously published methods and can be applied directly in surfactant research and regulatory submissions when experimental data are not available.

Predictive Toxicity Models for Chemically Related Substances: A Case Study with Nonionic Alcohol Ethoxylate Surfactant.

Predictive toxicity models, including interspecies correlation estimation (ICE) models, are reliable alternatives to animal toxicity testing. The ICE models describe mathematical relationships facilitating toxicity prediction from one surrogate test species to a species of unknown sensitivity. The ICE models were developed from curated aquatic toxicity data for 19 nonionic alcohol ethoxylate (AE) surfactants manufactured through the same process. Comparison of AE-ICE predictions with observed values from external validation datasets indicates a reasonable predictive accuracy. Model predictions were also closer to observed values than predictions from previously published ICE models for other substance groups. Comparison of acute fifth percentile hazard concentrations (HC5s) from species sensitivity distributions enhanced with AE-ICE predictions with chronic HC5s published elsewhere produced an acute-to-chronic ratio of 5, which was used to estimate chronic HC5s. With both acute and chronic HC5s for 14 AE substances, regressions were made relative to their respective liposome-water partitioning coefficients (log K lipw ), resulting in HC5-log K lipw relationships useful in estimating HC5s for AE substances with known composition but with limited or unavailable toxicity data. The findings from this case study further demonstrate that ICE models are viable alternatives to toxicity testing and could be used as weight of evidence in hazard assessment evaluations. Environ Toxicol Chem 2021;40:2073-2082. © 2021 SETAC.

Synthesis and Characterization of Novel Fatty Alcohol Ethoxylate Surfactants for Corrosion Inhibition of Mild Steel

Novel fatty alcohol ethoxylate surfactants (NFAES) C1:(C12–C14–EO30) and C2:(C16–C18–EO30) were synthesized and characterized, and the effect of an increase of the hydrocarbon chain length at the same numbers of ethoxylated groups of these surfactants on the corrosion of mild steel (MS) in 1 M HCl was studied by different methods. These have revealed that the inhibition efficiency (IE%) increases with increasing the dose and the hydrocarbon chain length at the same number of ethoxylated groups in the surfactants (NFAES). The surfactants (NFAES) have a perfect performance as corrosion inhibitors. The results revealed that C2 > C1 in the IE% at the same studied dose of each surfactant, The IE% reached 85% at the very low dose of 30 ppm. Potentiodynamic measurements (PP) revealed that the NFAES surfactants are working as mixed type of inhibitors for both cathodic (reduction) and anodic (oxidation) reactions. The critical micelle dose for C1 is 350 ppm while for C2 it is 30 ppm. IE% acquired from PP, electrochemical impedance spectroscopy, and electrochemical frequency modulation are approximatly the same. The surface morphology was analyzed and is discussed.

Rhamnolipids biosurfactants as potential modulators of phase and partitioning behavior in micellar systems of aliphatic alcohol ethoxylate surfactants

Abstract The impact of rhamnolipids (RL) biosurfactants presence on the phase-separation equilibrium, micellar properties and partitioning behavior of systems containing the aliphatic non-ionic surfactant Tergitol 15-S-7 (Tg7) was studied in this work. The cloud points of Tg7 solutions (1‐ 10% w/w) in water and sodium citrate (NaCit) buffers pH 7.00 were increased after the RL addition (0.25% w/w) while they were decreased in NaCit pH 5.00. The most marked changes were verified for those systems with low Tg7 concentrations ( 7°). As expected, the zeta potential (ζ) of non-ionic Tg7 systems was close to zero; however, ζ became clearly negative (≅ −20 mV) in NaCit pH 7.00 after the addition of RL. This finding suggested that RL, which is negatively charged at pH 7.00, self-incorporated into Tg7 micelles and conferred them its charge. Hydrodynamic diameter (Dh) was either increased (in citrate media) or decreased (in water) by the RL, depending on the changes caused in the critical packing parameter of mixed micelles. Interestingly, an exponential decay equation, useful for predictive purpose, was found to correlate the cloud point with the hydrodynamic diameter, thus evidencing the crucial role of micelle size/shape on the phase separation. The partitioning behavior of cibacron blue (CB) and malaquite green (MG), negatively and positively charged dyes respectively, in Tg7 aqueous micellar two-phase systems (AMTPS) was significantly affected by the RL 0.25% w/w. In AMTPS with pH 7.00, the RL induced opposite effects, either duplicating the partition coefficient of MG or reducing it to a half for CB. Attractive and repulsive electrostatic interactions between the negatively charged mixed micelles and the partitioned molecules would be responsible of these trends. These results demonstrate the role of RL as a modulator of partitioning behavior of charged molecules and its potential use to improve recoveries and selectivity in a purification protocol.

The Impact of Core Firing on EOR of Low Salinity-Surfactant Flooding

The combination of injection of lower saline brine and surfactant will increase recovery in sandstone rocks than either when any of the techniques is singly applied. In this work, core IFT test, pH test, flooding experiments and measurement of dispersion were performed on four core samples which were grouped into two: group A which were not fired and group B which were fired at a temperature of 500°C for 24 hours. Two low saline brines were prepared: LS1 which was derived by the dilution of seawater four times and LS2 which was derived by ten times diluting the seawater. The surfactant used was ethoxylated alcohol surfactant. Coreflood experiments were then performed on the rock samples starting with the injection of low saline followed by low saline brine combined with surfactant (LSS). Results from the experiments show that with the injection of LS1 brine and LSS1 higher increment in recoveries were obtained for group B than for group A cores. The same trend was also noticed with the injection of LS2 and LSS2. From the results, LS1 gave higher increment in oil recovery than LS2. Also LSS1 gave higher recoveries when compared with LSS2. In all the cases tested, core samples which were fired gave higher recoveries even though they had low permeabilities of 993 md for sample 3 and 1017 md for sample 4 than those which were not fired with higher permeabilities of 1050 md and 1055 md for samples 1 and 2 respectively. This was attributed to the alteration of wettability as well as that of permeability caused by sample firing. The dispersion profiles of the rock samples show that all samples are homogeneous.

Cold Water Detergency of Triacylglycerol Semisolid Soils: The Effect of Salinity, Alcohol Type, and Surfactant Systems

AbstractCold water detergency of triacylglycerol semisolid soils is much more challenging than liquid vegetable oils due to poorer interaction between surfactants and semisolid soil. This research seeks to improve the removal efficiency of semisolid soils below their melting points using surfactant‐based formulations containing different alcohol additives. To this end, cold water detergency of solid coconut oil and solid palm kernel oil was investigated in various surfactant/alcohol systems, including single anionic extended surfactants, single nonionic alcohol ethoxylate surfactants, and a mixture of anionic surfactants. A series of alcohols (2‐butanol, 1‐hexanol, 1‐heptanol, 1‐octanol, 1‐nonanol, and 1‐decanol) were added to the surfactant formulations to investigate cold water detergency improvement. While cold water detergency using surfactants alone was poor, it was considerably improved when optimum salinity (S*) and 1‐heptanol, 1‐octanol, or 1‐nonanol were introduced to the studied surfactant formulations. The maximum detergency of solid coconut oil exceeded 90% removal in the 0.1 w/v% C14‐15‐8PO‐SO4Na/0.2 w/v% 1‐octanol/4 w/v% NaCl system (a final optimized surfactant system) at a washing temperature of 10°C versus 22.9 ± 2.2% in the surfactant alone (not at optimum salinity and no additive). Further analysis showed that improved cold water detergency using surfactant/intermediate‐chain alcohols/NaCl could be correlated with high wettability (low contact angle) as well as favorable surfactant system‐soil interaction as observed by lower interfacial tension values. In contrast, the improved cold water detergency was observed to be independent of dispersion stability. This work thus demonstrates that surfactant system design, including additives, can improve cold water detergency of semisolid soils and should be further explored in future research.

Effect of Surfactant-Bile Interactions on the Solubility of Hydrophobic Drugs in Biorelevant Dissolution Media.

Biorelevant dissolution media (BDM) methods are commonly employed to investigate the oral absorption of poorly water-soluble drugs. Despite the significant progress in this area, the effect of commonly employed pharmaceutical excipients, such as surfactants, on the solubility of drugs in BDM has not been characterized in detail. The aim of this study is to clarify the impact of surfactant-bile interactions on drug solubility by using a set of 12 surfactants, 3 model hydrophobic drugs (fenofibrate, danazol, and progesterone) and two types of BDM (porcine bile extract and sodium taurodeoxycholate). Drug precipitation and sharp nonlinear decrease in the solubility of all studied drugs is observed when drug-loaded ionic surfactant micelles are introduced in solutions of both BDM, whereas the drugs remain solubilized in the mixtures of nonionic polysorbate surfactants + BDM. One-dimensional and diffusion-ordered 1H NMR spectroscopy show that mixed bile salt + surfactant micelles with low drug solubilization capacity are formed for the ionic surfactants. On the other hand, separate surfactant-rich and bile salt-rich micelles coexist in the nonionic polysorbate surfactant + bile salt mixtures, explaining the better drug solubility in these systems. The nonionic alcohol ethoxylate surfactants show intermediate behavior. The large dependence of the drug solubility on surfactant-bile interactions (in which the drug molecules do not play a major role per se) highlights how the complex interplay between excipients and bile salts can significantly change one of the key parameters which governs the oral absorption of poorly water-soluble drugs, viz. the drug solubility in the intestinal fluids.

Synthesis and Characterization of Novel Surfactants based on 2‐Hydroxy‐4‐(Methylthio)Butanoic Acid Part 3: Microemulsions from Nonionic Sulfoxide Ester Surfactants

AbstractIn this work, ester sulfoxide (ESO) surfactants based on 2‐hydroxy‐4‐(methylthio) butyric acid are shown to have temperature‐sensitive microemulsion phase behaviors. Both C10 (C10ESO) and C12 (C12ESO) surfactants studied contained one sulfoxide unit in the structure. Phase inversion temperatures (PIT) and interfacial tensions (IFT) between water‐rich and oil‐rich phases have been measured for ternary systems of water, oil, and sulfoxide surfactants. Hydrophilic–lipophilic deviation (HLD) parameters of these surfactants were obtained by fitting the experimental data to a semiempirical HLD equation. The characteristic surfactant parameter and temperature sensitivity of C10ESO and C12ESO surfactants were obtained and compared with similar ethoxylated alcohol surfactants. By comparing the characteristic parameters of these surfactants with those of ethoxylated alcohol surfactants, it was shown that one sulfoxide ester moiety is equally hydrophilic as approximately 5 ethylene oxide groups. The temperature sensitivity of the ESO was roughly a factor of four less than ethoxylated surfactants based on the temperature coefficient of the HLD equation.

Liquid-liquid equilibria for (volatile fatty acids + water + alcohol ethoxylates): Experimental measurement of pseudo-ternary systems

Abstract Experiments were conducted to establish the phase diagrams for ternary systems containing (acetic acid or propionic acid or butyric acid + water + alcohol ethoxylate surfactant) at 308.15 K and ambient pressure. Results indicated that the systems belong to Type 1 Treybal classification with water–surfactant binary pair exhibiting partial miscibility. The liquid–liquid equilibrium data were used to determine the ability of the surfactant to extract the acids from aqueous solutions. The calculated distribution coefficients and separation factors indicated that the effectiveness of the surfactant to extract acids follow the trend: butyric acid > propionic acid > acetic acid. The effectiveness of the surfactant to extract butyric acid from aqueous solutions is similar to previously studied environmentally-friendly solvents with added benefit of being non-inhibitory to microbial growth and metabolism. These characteristics of the alcohol ethoxylate used in this study could be exploited for the development of an extractive butyric acid fermentation process.

Synthesis of stable nanoparticles at harsh environment using the synergistic effect of surfactants blend

Synthesis of nanoparticles (NPs) that can withstand high temperature and high salinity (HT-HS) is a big challenge in the research community. A novel strategy to synthesize stable nanoparticles under harsh environment (HT-HS) is proposed in this work by using the synergistic effect of a surfactant mixture. Long-term stable iron oxide nanoparticles at HT-HS conditions were produced and stabilized by two different surfactant classes, i.e. sulfonate surfactant for high temperature resistance and ethoxylated alcohol surfactant for high salinity resistance. The results prove that the new strategy could be used for production of stable NPs which is suitable for enhanced oil recovery application.

Formulation of microemulsion-based washing agent for oil recovery from spent bleaching earth-hydrophilic lipophilic deviation concept

The disposal of spent bleaching earth (SBE), an industrial refining waste from the bleaching process, is a crucial environmental issue. The objective of this work was thus to formulate a microemulsion-based washing agent for the removal of residual rice bran oil from SBE using the hydrophilic–lipophilic deviation (HLD) concept. The HLD equation was used to calculate the optimum salinity at various temperatures in the washing agent solution based on the alkane carbon number (ACN) of the rice bran oil. Three fatty alcohol ethoxylate surfactants (Dehydol LS series) were selected for use as nonionic surfactants. From the HLD equation and phase experiments, Dehydol LS3TH was selected to formulate the microemulsion-based washing agent for oil recovery from the SBE. The HLD equation predicted a Winsor Type III microemulsion to occur at 8.5 wt.% of NaCl at 25 °C. Phase behavior studies demonstrated that a Type III microemulsion occurred over a NaCl concentration range of 10–20 wt.%. From these results, a correlation was confirmed between the theoretical HLD prediction and the experimental phase behavior. In the oil recovery study, the microemulsion-based washing agent provided the highest total oil extraction efficiency: up to 71.38 ± 1.75% at the optimum salinity of 15 wt.% NaCl, and a contact time of 30 min at 25 °C. Thus, the HLD concept for predicting microemulsion formulation was found to be an effective way to formulate a microemulsion-based washing agent for vegetable oil removal from SBE.

Polymer Film Dewetting by Water/Surfactant/Good-Solvent Mixtures: A Mechanistic Insight and Its Implications for the Conservation of Cultural Heritage.

Aqueous nanostructured fluids (NSFs) have been proposed to remove polymer coatings from the surface of works of art; this process usually involves film dewetting. The NSF cleaning mechanism was studied using several techniques that were employed to obtain mechanistic insight on the interaction of a methacrylic/acrylic copolymer (Paraloid B72) film laid on glass surfaces and several NSFs, based on two solvents and two surfactants. The experimental results provide a detailed picture of the dewetting process. The gyration radius and the reduction of the Tg of Paraloid B72 fully swollen in the two solvents is larger for propylene carbonate than for methyl ethyl ketone, suggesting higher mobility of polymer chains for the former, while a nonionic alcohol ethoxylate surfactant was more effective than sodium dodecylsulfate in favoring the dewetting process. FTIR 2D imaging showed that the dewetting patterns observed on model samples are also present on polymer-coated mortar tiles when exposed to NSFs.

Polymer Film Dewetting by Water/Surfactant/Good‐Solvent Mixtures: A Mechanistic Insight and Its Implications for the Conservation of Cultural Heritage

AbstractAqueous nanostructured fluids (NSFs) have been proposed to remove polymer coatings from the surface of works of art; this process usually involves film dewetting. The NSF cleaning mechanism was studied using several techniques that were employed to obtain mechanistic insight on the interaction of a methacrylic/acrylic copolymer (Paraloid B72) film laid on glass surfaces and several NSFs, based on two solvents and two surfactants. The experimental results provide a detailed picture of the dewetting process. The gyration radius and the reduction of the Tg of Paraloid B72 fully swollen in the two solvents is larger for propylene carbonate than for methyl ethyl ketone, suggesting higher mobility of polymer chains for the former, while a nonionic alcohol ethoxylate surfactant was more effective than sodium dodecylsulfate in favoring the dewetting process. FTIR 2D imaging showed that the dewetting patterns observed on model samples are also present on polymer‐coated mortar tiles when exposed to NSFs.

Predicting Octanol/Water Partition Coefficients of Alcohol Ethoxylate Surfactants Using a Combination of Molecular Dynamics and the Conductor-like Screening Model for Realistic Solvents

We present a hybrid modeling strategy for the prediction of octanol/water partition coefficients for alcohol ethoxylate surfactants of varying chain lengths. The strategy makes use of molecular dynamics (MD) simulations for the generation of molecular conformations in the presence of a solvent. A clustering of the conformations from the MD trajectories was carried out based on principal component analysis of their dihedral angles. Representative conformations thus selected were then used in the conductor-like screening model for realistic solvents (COSMO-RS). Each conformation has been assigned a weight using an equation derived on the basis of its probability of occurrence in the MD trajectory. Experimental partition coefficients were reproduced within conformation-independent accuracy of COSMO-RS despite the size and flexibility of the ethoxy chain otherwise posing a challenge on their solvation modeling.

Optimizing Jatropha biodiesohol composition for a suitable kinematic viscosity by a phase diagram and mixture design

Jatropha biodiesohol (JBH) is an alternative microemulsion-based fuel that promotes the use of non-edible vegetable oils and bioethanol, replacing fossil fuel consumption. Unprocessed vegetable oil is more eco-friendly than transesterified biodiesel, which consumes a substantial amount of chemicals, energy, and water. However, this unprocessed vegetable oil has a limitation on the injection system of diesel engines because of its high viscosity. Microemulsification technique is introduced to alleviate this problem by adding an alcohol ethoxylate surfactant (LS) and bioethanol. The ethylene oxide group (at LS1, LS3 and LS7) of the surfactant, the ratio of the ethanol–surfactant (E/S ratio), and the ethanol and surfactant content (E/S content) were studied to improve the miscibility of Jatropha biodiesohol. To screen for the optimum product, those factors forming a water in oil microemulsion with transparent, clear, and homogeneous JBH were screened for in phase behavior experiments and kinematic viscosity experiments. LS1 is the most appropriate for solubilizing all components because of its low HLB (hydrophilic–lipophilic balance). The increase E/S ratio and E/S content enhance the reduction of the kinematic viscosity. A mixture design was applied to optimize the composition of each component to predict the desired kinematic viscosity. Compared with the other models, the results indicate that the full cubic model of a {3,3} simplex lattice model with three interior points and a centroid in the mixture design (providing) displayed the best fit when screening and optimizing the kinematic viscosity with R2=0.998 and MAPE=5.031%.

Salt- and temperature-stable quantum dot nanoparticles for porous media flow

The transport of colloidal nanoparticles (NPs) through porous media is a well-studied phenomenon at ambient temperature and in low-to-zero salinity water found in aquatic systems. Little is known at much higher temperatures and salinities such as conditions found in petroleum reservoirs, thus limiting the possible use of NPs in downhole oilfield applications. Using 3-nm CdSe quantum dots (QDs) as a model material, we report that NPs can be prepared with excellent colloidal stability at high ionic strengths and elevated temperatures. QDs with an outer coating of a nonionic ethoxylated alcohol surfactant showed little aggregation in synthetic seawater with ionic strength of 0.55M and 1M NaCl brine solution based on dynamic light scattering analysis. They showed colloidal stability up to 70°C, close to the cloud point temperature of the nonionic surfactant. They further showed nearly unimpeded flow behavior when carried in high-salinity water through a packed column of crushed calcite or sandstone mineral at room temperature. QDs were successfully passed through a medium-permeability Berea sandstone core (100mDa) at 17atm, 25°C, and 8mL/h. The preparation strategy for salt- and temperature-stable QDs is applicable to a wide range of particle sizes and compositions, toward the general handling and use of functional NPs in high-salinity environments.

Phase Behaviors of Vegetable Oil-Based Microemulsion Fuels: The Effects of Temperatures, Surfactants, Oils, and Water in Ethanol

Vegetable oil-based microemulsification not only reduces the high viscosity of vegetable oils but also enhances the miscibility of polar and oil phases. In addition, vegetable oil-based microemulsion fuels produce lower pollutant emissions compared to neat No.2 diesel. Since the stability of microemulsion fuels is temperature sensitive, the effect of temperature on the microemulsion phase behavior should be evaluated. The overall goal of this study is to formulate temperature-robust microemulsion fuels by studying the effect of temperature on phase behaviors of different systems of vegetable oil-based reverse micelle microemulsions. Our results demonstrate that, when using an alcohol ethoxylate surfactant as a renewable surfactant, it is possible to formulate microemulsion fuels with comparable properties to nonionic surfactant evaluated in previous studies. Further, mixtures of nonedible oil (algae mixed with castor) were found to have comparable properties to edible oil (canola) used to produce microemu...

Influence of the dye transfer inhibitors for the washing of softened cotton fabric

In this, work the performance of several dye transfer inhibitors (DTI) copolymers (PVP, PVNO and PVNO with PVP) was tested for use as DTIs in washing softened undyed cotton fabric, in the presence of a direct dye in the washing bath, with and without water hardness. Three direct dyes were tested: red, blue and yellow. The detergent used was composed of an LAS anionic surfactant and a non-ionic fatty alcohol ethoxylate surfactant with 7 m. OE, both separately and in the different molar proportions anionic with non ionic, at a total concentration of 5 × 10−3 M, and in the presence of zeolite as a builder. Washing temperature was 40°C and washing time was 30 min. Staining of the softened undyed cotton fabric was assessed as the CIELAB colour differences between the original fabric and the stained fabric after washing.The different DTIs and the dye in the washing bath with and without water hardness were tested.