Nonylphenol Ethoxylates Research Articles

Potential methanogenic and degradation of nonylphenol ethoxylate from domestic sewage: unravelling the essential roles of nutritional conditions and microbial community

ABSTRACT Nonylphenol ethoxylathe (NPEO) is a non-ionic surfactant of increasing concern, used in the formulation of laundry detergents and is frequently found in aquatic environments. The purpose of this study was to evaluate the effects of yeast extract (YE) and sodium fumarate (SF) in NPEO removal from domestic sewage under anaerobic conditions via central composite rotatable design (CCRD) and response surface methodology (RSM). Experiments were designed by varying concentrations of NPEO (1.6–5.8 mg L−1), YE (131.8–468.2 mg L−1) and SF (97.7–602.3 mg L−1) in batch reactors. SF and YE addition significantly influenced NPEO removal and CH4 production. Optimal values of YE (400 mg L−1) and SF (200 mg L−1) result in removal efficiency of 97% for 5 mg L−1 of NPEO, being mostly removed by biodegradation (86%). Meanwhile COD removal was 95% and methane yield was 134 ± 4 NmLCH4 g−¹CODremoved. The most abundant Bacteria genus identified were Macellibacteroides, Longilinea, Petrimonas and Proteiniphilum, while for Archaea, Methanosaeta and Methanoregula were the genera identified in higher relative abundances in optimized conditions.

Photocatalytic efficiency of titania nonylphenol ethoxylate composite thin films under solar irradiation

Photocatalytic efficiency of titania nonylphenol ethoxylate composite thin films under solar irradiation

Addition of surfactants to Low Salinity Waterflooding in microfluidics system to increase oil recovery

This study was conducted to investigate the phenomenon of oil removal from inside pores using a self-designed microfluidic test kit. An artificial micromodel chip as a representation of porous rocks has been created with a uniform pore structure design and made of PMMA (Polymethyl Methacrylate) material. The micromodel chip has a porosity of 27.8% as well as a permeability of 2.7 Darcy. By using the microfluidic test kit, this study has investigated how low salinity water (LSW) injection with MgCl2 divalent ions and the addition of anionic surfactant, linear alkylbenzene sulfonate mixed with nonionic surfactants, nonylphenol ethoxylate (NP-10) affects to oil recovery. The injection of LSW and surfactant solution was carried out with different injection stages, injection rates and surfactant solutions concentrations. Visual images during the injection process are recorded for analysis, which is the advantage of dynamic testing using this microfluidic test kit over conventional coreflooding. From this study, it is indicated that the selection of ions contained in LSW affects the success of LSW injection. Reducing the surfactant injection rate from 50 μL/min to 20 μL/min can increase the oil recovery from 1.27% to 4.29%. Oil recovery was also higher on surfactant injection which resulted in lower interfacial tension of the system based on the calculation of interfacial tension obtained from the Chun-Huh and Ghosh equations from the Winsor test. From all injection scenarios carried out in this study, the highest increase in oil recovery of 26.87% OOIP was obtained by injecting surfactant solutions directly in the secondary stage without prior LSW injection.

Occurrence of Linear Alkylbenzene Sulfonates, Nonylphenol Ethoxylates and Di(2-ethylhexyl)phthalate in Composting Processes: Environmental Risks

Composting is an important waste management strategy, providing an economical and environment-friendly approach to sanitizing and stabilizing biosolids for land soil amendment. However, the resulting product can contain a large number of organic pollutants that may have adverse effects on the ecosystem. This paper presents the occurrence of eight widely used organic pollutants (four linear alkylbenzene sulfonates (LAS C10-C13), nonylphenol and its mono- and di-ethoxylates (NPE) and a di(2-ethylhexyl)phthalate (DEHP)) in full-scale composting processes. LAS homologues were detected at the highest concentrations (range of ∑LAS: 2068–9375 mg kg−1 dm), exceeding the limit fixed in the EU Directive draft. The concentration levels of the NPE and DEHP were significantly lower (up to 27.5 and 156.8 mg kg−1 dm, respectively) and did not exceed their fixed limits in the EU Directive draft. Ecotoxicological risk assessment for when compost is amended onto soils has also been evaluated. The concentrations measured represented a medium-low risk for most compounds, although it was not enough in the case of LAS C11 and C13 and NP.

Synthesis, properties, and applications of an anionic–nonionic Gemini surfactant for highly efficient remediation of perchloroethylene-contaminated aquifers

Monomeric surfactants are currently used for the remediation of dense non-aqueous phase liquid-contaminated groundwater. However, they result in low remediation efficiency because of their high adsorption loss and low temperature and salt resistance. In this study, a novel and green Gemini surfactant, SNE(10)SID (sodium nonylphenol ethoxylate (10) sulfoitaconate diester), was synthesized for subsurface environment characteristics through esterification and sulfonation. This surfactant consisted of two long and straight hydrophobic chains, two selfsame non-ionic portions, and two anionic moieties covalently connected to each other by an itaconic acid spacer. The critical micelle concentration was ∼10−4 M. The interfacial tension between SNE(10)SID and perchloroethylene (PCE) was significantly low, and the value was found to be 1.0 mN/m. SNE(10)SID exhibited excellent activity under conditions of low temperature and in high salt systems. The solubility of PCE was up to 8863 mg/L in a 4 wt% SNE(10)SID solution, which was two orders of magnitude higher than the solubility recorded in pure water. SNE(10)SID exhibited a low adsorption loss (only 0.8 mg/g at a concentration of 2 g/L in medium sand). The PCE desorption ability of the surfactant was far significantly higher than the PCE desorption abilities of other monomeric surfactants in various aquifer media. Under conditions of dynamic flushing, the low-viscosity SNE(10)SID solution exhibited excellent remediation ability when PCE-contaminated simulated aquifers were used for the studies. The total PCE removal rate reached was 87.5% after the flushing of 10 pore volumes. These results revealed that SNE(10)SID was an excellent surfactant that could be used to realize efficient aquifer remediation.

Nonylphenol Ethoxylate Surfactants Modified by Carboxyl Groups for Foam EOR at High-Salinity Conditions

High mineralization of water complicates the use of foam in reservoir conditions. Anionic–nonionic surfactants are one of the best candidates for these conditions since they have both high surface activity and salt tolerance. One of the ways to obtain anionic–nonionic surfactants is to modify nonionic surfactants by an anionic group. The type of the group and its chemical structure can strongly affect the properties of the surfactant. In this work, widely-produced nonionic surfactant nonylphenol (12) ethoxylate (NP12EO) was modified by new types of carboxylic groups through the implementation of maleic (NP12EO-MA) and succinic (NP12EO-SA) anhydrides with different saturation levels. The main objectives of this work were to compare synthesized surfactants with nonionic precursor and to reveal the influence of unsaturated bonds in the carboxyl group on the properties of the foam. NaCl concentration up to 20 wt% was used to simulate high mineralization conditions, as well as to assess the effect of unsaturated bonds on foam properties. Synthesized anionic–nonionic surfactants retained surfactant solubility and long-term stability in high-salinity water, but have better foaming ability, as well as higher apparent viscosity, in porous media. The presence of an unsaturated bond in NP12EO-MA surfactant lowers foaming ability at high mineralization.

Non‐linearchanges in phase inversion temperature for oil and water emulsions of nonionic surfactant mixtures

AbstractHydrophilic–lipophilic deviation (HLD) is a semiempirical framework for surfactant‐oil–water (SOW) formulation that has effectively assimilated SOW properties such as phase inversion temperature (PIT) and Winsor Type I ↔ II ↔ III ↔ IV microemulsion behavior. The HLD system's reliance on surfactant and oil parameters necessitates their experimental determination when relevant and accurate values are not available. In this study, experiments have been of the type commonly used to generate test surfactant HLD parameters based on perturbation of a well‐defined SOW reference system and assumption of linear mixing behavior for PIT versus component mole fractions. The reference SOW compositions comprisedn‐octane, 0.01 M aqueous NaCl, and puren‐decyl tetraethylene glycol ether (C10E4) reference surfactant. Test surfactants were primary alcohol ethoxylates and nonylphenol ethoxylates comprising disperse PEG (polyethylene glycol) chain lengths that are inherent to commercial production of nonionic ethoxylate surfactants. We observe non‐linear behavior of PIT versus test surfactant mole fraction, even when accounting for surfactant concentration effects, so the desired linear correlation that could otherwise be used to assign an HLD parameter has not been obtained. Since an objective of this study has been to improve the predictive utility of the HLD framework for commercial nonionic surfactants, relevant terms in the HLD equation have been assessed in terms of their potential contributions to non‐linear behavior. One current working‐explanation relates substantial non‐linear PIT contribution to oil‐like surfactant components in disperse commercial ethoxylates.

Submerged membrane filtration process coupled with powdered activated carbon for nonylphenol ethoxylates removal.

A combination of a submerged membrane filtration system and powdered activated carbon (PAC) was investigated for nonylphenol ethoxylates removal. Both filtration flux and initial powdered activated carbon dosage had significant effects on the micropollutants removal efficiency. The best performance was achieved under the filtration flux of 20 L/m2.h and the initial powdered activated carbon of 50 mg/L. The removal efficiencies of nonylphenol ethoxylates was obtained at 75±5% in the first 60 hours, and then decreased at 55±7% and 23±11% in the following hours, respectively. As observed, over 65% of dissolved organic carbon mass adsorbed into powdered activated carbon that was suspended in the bulk phase, and the remainder was adsorbed into powdered activated carbon that deposited on the membrane surface. It reveals that the combination between submerged membrane filtration and PAC could be an effective solution for enhancing removal of micropollutants from water.

Photocatalytic efficiency of titania nonylphenol ethoxylate composite thin films under solar irradiation

Photocatalytic efficiency of titania thin-films on ITO synthesized in the presence of nonylphenol-surfactants containing different numbers of ethoxylate-units was investigated under solar-irradiation. A colorless transparent titania-gel formed in the non-aqueous medium in the presence of nonylphenol-10-ethoxylates while milky white opaque gel was observed with nonylphenol-35-ethoxylates. They were coated on ITO plate by dipping method and calcined at 350, 500 and 700 °C. The XRD, IRRAS, EDS, SEM and AFM analyses revealed that different composite nanostructures are formed by calcinations of Ti-nonylphenol-35-ethoxylates at 350 and 500 °C. The photocatalytic-efficiencies of the composite films are better than the other titania nanostructures. Transparency and band-gap energy evaluated from transmittance measurements demonstrated that visible-light responsive Ti-nonylphenol-35-ethoxylates composites are more efficient catalysts than UV-absorbable Ti-nonylphenol-10-ethoxylates films. The photocatalytic degradation rate of the methylene-blue on the catalysts was calculated using the Langmuir-Hinshelwood equation and its modified form derived in this study by considering intensity changes in solar light. The dye degradation efficiency of the Ti-nonylphenol-ethoxylate films changes in the 58–74% range after 2 h of irradiation in 0.02 mM MB solution. The solution completely decolorized after 8 h of irradiation on the TiNP-35 catalysts calcined at 350 °C.

An experimental investigation on the effect of surfactant for the transesterification of soybean oil over eggshell-derived CaO catalysts

• Nonylphenol ethoxylates was used as a co-solvent in transesterification reaction. • The use of surfactant accelerates the rate of the biodiesel production reaction. • CaO catalyst from eggshells showed high efficiency in biodiesel production. • The use of surfactant decreases the required alcohol/oil ratio. • The thermogravimetric analysis proved to be efficient for determining the FAME yield. Biodiesel is a biodegradable and renewable fuel, that generally consists of fatty acid methyl ester (FAME) produced by transesterification of lipids using methanol and a catalyst. Calcium oxide (CaO) is a heterogeneous catalyst that has been extensively studied to produce biodiesel due to its high catalytic activity. In addition, and in order to avoid mass transfer limitations that would slow down the reaction, it is also common to use a co-solvent. Thus, this work aims to evaluate the use of the surfactant Nonylphenol seven Ethoxylates (NP7EO) for the CaO-catalyzed transesterification of soybean oil. For this study, chicken eggshell was the source of calcium used to produce the CaO for the reaction. This work represents one of the few articles where transesterification was performed using a surfactant combined with a biobased and residual source of Ca. An experimental design was performed to evaluate the surfactant concentration and reaction time. Another factorial experimental design was carried out considering factors such as reaction time, catalyst concentration, and methanol-to-oil molar ratio. Ultimately, the model predicted by the experimental design was shown to be significant and the highest yield obtained after a 3 h reaction time was 98.95% with a 5 wt% catalyst loading and a 7:1 methanol-to-oil molar ratio using 1 wt% of surfactant and operated at 65 °C. The results showed that the surfactant allowed reducing the methanol-to-oil molar ratio and reaction time, which ultimately could contribute in decreasing the biodiesel production costs.

The Investigation into Neurotoxicity Mechanisms of Nonylphenol: A Narrative Review.

Background Nonylphenol (NP), a chemical compound widely used in industry, is the result of the nonylphenol ethoxylate decomposition and it is known as an estrogen-like compound. Numerous studies and researches have shown that it has many destructive functions of various organs such as the brain. This toxicant causes oxidative stress in the cortex and hippocampus cells, which are two essential regions to preserve memory and learning in the brain.Methods This review examines recent findings to better understanding the mechanisms of NP neurotoxicity. We used Scopus, Google Scholar, and PubMed databases to find articles focused on the destructive effects of NP on the oxidative stress pathway and its defense mechanisms.Results NP has potential human health hazards associated with gestational, peri- and postnatal exposure. NP can disrupt brain homeostasis in different ways, such as activation of inflammatory factors in brain especially in hippocampus and cortex, disruption of the cell cycle, changes in neuron, dendrites and synapses morphology, disruption of extra and intracellular calcium ion balance and also memory and learning disorders

Determination of Endocrine-Disrupting Nonylphenols and Nonylphenol Carboxylates by High-Performance Liquid Chromatography-Tandem Mass Spectrometry: Levels in German Food after Restriction

Nonylphenols (NPs) and nonylphenol carboxylates (NPECs) are products of the biodegradation of nonylphenol ethoxylates (NPEOs), which is a widely used group of nonionic surfactants. These compounds are persistent, toxic, and exhibit estrogenic activity. Global scientific and public discourse has revealed the consequences of long-term dietary exposure to these endocrine disrupters. Since 2005, the utilization and sale of NPEOs and NPs have been regulated in some industrial applications by Directive 2003/53/EC of the European Union (EU). The objective of this investigation was to assess the NPs and NPECs concentration levels in foodstuffs following the implementation of the EU directive. Using a method based on high-performance liquid chromatography combined with tandem mass spectrometry (HPLC-MS), NPs and NPECs were determined in the same German food basket that was examined before the restriction. NPs were detected in 22 of the 24 food samples, whereas NPECs were below the limit of detection. The concentrations of NPs on a fresh weight basis varied between 0.1 and 6.3 μg kg−1. Based on the data of food consumption rates in Germany and the concentrations of NPs in the food samples, the daily NP intake for an adult was determined to be 2.7 µg day−1, which is one-third of the value found in the 2002 study. However, our findings revealed that NPs remain ubiquitous in foods at relevant concentrations, which highlights the need for further examinations in particular the isomer-specific aspects. This is especially important as nonylphenol is found in human blood in many studies.

Impact of phenolic compounds on free amino acid contents and electrophoretic patterns of the Nile Tilapia, Oreochromis niloticus

The present research was designed to determine the free amino acids (FAAs) composition and electrophoretic protein patterns by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in Oreochromis niloticus exposed to 1/10 LC50-96 hrs of phenol and nonylphenol ethoxylate 9 (NPEO 9) under laboratory condition for 4 weeks, in an attempt to develop sensitive bio-indicators for evaluation of pollution effects. Variations of FAAs were apparent in both treated groups. Significant increases were recorded in all individual amino acids including essential and non-essential ones, except for proline for both treated groups and leucine for phenol exposed fish group where they decreased significantly. The electrophoretic analysis of protein of the skeletal muscle homogenate using SDS-PAGE indicated that the control group yielded 10 fractions of molecular masses between 166 and 23 kDa. A total number of 9 bands were separated from fish of phenol group; they were varied from 168 to 23 kDa. However, 6 bands only were separated from fish of the NPEO 9 group; they were varied from 157 to 28 kDa. The muscle protein extract from fish of the phenol group showed five unique bands (168, 96, 68, 52, and 39 kDa). Moreover, fish that were exposed to NPEO 9 group showed three unique bands (157, 92, and 72 kDa). The highest similarity index S value observed between phenol and control groups was 0.37, followed by 0.33 between NPEO 9 group and the control one. This could be an indicator of changes in protein metabolism due to phenol and NPEO 9 pollution.

Biodegradation of Nonylphenol Ethoxylate in waste water by Penicillium chrysogenum

Current research aims to isolate fungal isolates capable of biodegrading Nonylphenol Ethoxylate (NPEOs) from secondary activated sludge. Samples were collected from Zenin wastewater treatment plant, El-Giza, Egypt. Physical and chemical analysis were performed. Screening of microbial isolates capable of degrading Nonylphenol Ethoxylate was performed on basal salts medium with Nonylephenol Ethoxylate as the only carbon source. Quantification of the residual amount of the (NPEOs) was determined by using a liquid chromatography technique. Morphological identification of the most promising fungal isolates degrading NPEOs was performed based on current universal keys, Penicillium database management system and molecular technique 18S rDNA using ITS1 (forward) and ITS4 (reverse) primers. Cytotoxicity test for microbes was performed by using different concentrations of NPEOs. Results revealed that eight microbes were isolated, which achieved the highest percentage of NPEOs biodegradation ( 70 - 80 %) .One novel species named Penicillium chrysogenum was able to biodegrade (NPEOs) (80%). In case of the Penicillium chrysogenum cytotoxic activity against mammalian cells from African green monkey kidney cells was detected under these experimental conditions (CC50) was 46.5 ± 4.8 µg/ml and the inhibitory cytotoxic activity against normal human lung fibroblast cells was detected under these experimental conditions with CC50 was 74.1 ± 6.1 µg/ml.

Determination of specific urinary nonylphenol metabolites by online-SPE-LC-MS/MS as novel human exposure biomarkers

Nonylphenol (NP) is an endocrine disrupting and ecotoxic substance that has been detected in a variety of environmental matrices. It is utilized for the production of non-ionic nonylphenol ethoxylate (NPEO) detergents and other high production volume chemicals. Human biomonitoring data are scarce and mostly limited to the non-oxidized NP, which is ubiquitous in the (laboratory) environment and susceptible to external contamination. Here, we describe a sensitive, precise, accurate and rugged analytical method for the determination of OH-NP and oxo-NP, two potential alkyl-chain-oxidized metabolites of NP in human urine. We used single isomer standards, obtained by custom synthesis, for the quantification of the sum of the respective isomers. After enzymatic hydrolysis of potential urinary phase II conjugates, urine samples were analyzed by online turbulent flow chromatography for analyte enrichment and matrix depletion coupled to reversed phase liquid chromatography with negative electrospray-ionization triple quadrupole tandem mass spectrometry detection (online-SPE-LC-MS/MS). Quantification was performed by stable isotope dilution analysis. Limits of quantification in urinary matrix were 0.5 µg/L for OH-NP and 0.25 µg/L for oxo-NP. Mean relative recoveries were 101–105% (OH-NP) and 112–117% (oxo-NP) and the method imprecision (CV) in matrix was below 5%. In spite of extensive use restrictions in the EU since 2003, we could quantify OH-NP and oxo-NP in 94% and 47% of spot urine samples from the general German population (n = 32) collected in 2014. Thus, both metabolites seem suitable as sensitive and specific urinary biomarkers of NP exposure for future human biomonitoring population studies. Currently this method is used to quantitatively investigate human NP metabolism and to derive urinary metabolite excretion fractions that can be used to calculate external doses based on urinary biomarker concentrations.

Use of MCM‐41 as an Efficient Adsorbent for Removal of Nonionic Surfactant from Aqueous Solutions

AbstractThe as‐synthesized MCM‐41 and its modified forms are used as adsorbents for the removal of nonylphenol ethoxylate (NP‐10) from aqueous solutions. The partial template containing MCM‐41 is prepared by treating the as‐synthesized sample with ethanolic ammonium nitrate solution. Complete removal of the template is performed using the calcination process. The prepared adsorbents are characterized by X‐ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy, and nitrogen physisorption techniques. The effect of adsorbent weight, pH, contact time, and initial concentration on the adsorption efficiency is studied. The equilibrium adsorption data are well defined, and they are fitted with Langmuir isotherm model. The maximum adsorption capacities (qm) and pseudo‐second‐order rate constants (k2) are calculated. The best adsorbent, in terms of removal efficiency, results to be the thermally treated MCM‐41, characterized by the highest surface area, and thus with the largest porosity. Specifically, the removal efficiency for NP‐10 is around 84% (558 mg g−1) with an initial concentration of 700 mg L−1, which is increased to 91% (455 mg g−1) for a 500 mg L−1 initial concentration. Thermodynamic studies depict that the adsorption of NP‐10 onto MCM‐41 is an endothermic process and the spontaneity is controlled by entropy.

The Effect of Non- Ioic Surfactant in Gravity Drainage Processes in the Reservoir to Increase Oil Production at a Laboratory Scale

Chemical flooding is one of the methods used to increase oil recovery. One of the chemical flooding used is alkaline surfactant, where the alkaline and surfactant function is to reduce interface stress and form microemulsion . In this study, a screening of surfactant was conducted in order to determine which surfactants were compatible and then injected to increase oil production. The surfactants used in this study were non-ionic surfactants namely Poly Ethylene Glycol Monooleate (PEGM), Nonyl Phenol Ethoxylate (NP-6), Poly Ethylene Glycol Diolate (PD) and Sodium Dodecyl Benzene (SDB) with surfactant concentrations of 0.3 %, NaCL concentrations of 0%, 2% and 5%, and alkaline concentrations (NaOH and Na2CO3) of 0.05%, 0.1% and 0.5%. The result obtained from the measurement of Interfacial Tension (IFT) surfactant PEGM 3% at the brine concentration of 2% was 0.012638 Dyne/cm. After that imbibition testing was performed to perceive the ability of surfactants to bind oil in rock pores, the highest oil recovery was 75.7% in PEGM surfactant concentration of 0.3%, salinity of 2%, and NaOH alkaline of 1.2%.

Degradation of Nonylphenol Ethoxylate-10 (NPE-10) by Mediated Electrochemical Oxidation (MEO) Technology

Nonylphenol ethoxylate (NPE-10) is a non-ionic surfactant that is synthesized from alkylphenol ethoxylate. The accumulation of NPE-10 in wastewater will endanger the ecosystem as well as the human being. Nowadays, NPE-10 can be degraded indirectly by using an electrochemical treatment by the advancement of technology. Thus, this study is aimed to evaluate the electro-degradation potential of NPE-10 by MEO using Ce(IV) ionic mediator. In addition, the influence of Ag(I) ionic catalyst in the performance of MEO for the degradation of NPE-10 was also observed. The potency of MEO technology in the NPE-10 degradation was evaluated by voltammetry technique and confirmed by titrimetry and LC-MS analysis. The results showed that in the absence of Ag(I) ionic catalyst, the degradation of NPE-10 by MEO was 85.93%. Furthermore, when the Ag(I) ionic catalyst was applied, the performance of MEO in degradation of NPE-10 was improved to 95.12%. The back titration using Ba(OH)2 confirmed the formation of CO2 by 46.79%, whereas the redox titration shows the total of degradation organic compounds by 42.50%. It was emphasized by the formation of two new peaks in the LC-MS chromatogram. In summary, our results confirmed the potential of MEO technology for the NPE-10 degradation.

Studies on influence of characteristics of surfactant and foam on foam concrete behaviour

This paper describes an extensive laboratory-based investigation conducted to evaluate the relative performance of foam produced with two different synthetic surfactants namely Sodium lauryl sulphate (SLS) and Nonylphenol ethoxylate (NPE) along with an additive Carboxymethyl cellulose sodium salt (CMC) for use in foam concrete. The different essential characteristics of foam and surfactants such as initial foam density, foam stability, average bubble size and viscosity of surfactant solution are investigated in the present study through systematic experimental design based on response surface methodology. Further, based on studies on microstructure of foam concrete, it is found that selection of surfactant and CMC concentration have significant influence on foam characteristics and hence on the air void size distribution of foam concrete. In addition, the dependence of the compressive strength and water permeation characteristics of foam concrete on the air void size parameters of concrete is also investigated. Experimental outcomes indicate that increase in surfactant concentration from 3% to 6% results in 24%–44% reduction in median air void diameter in concrete which eventually led to 29%–37% enhancement in compressive strength of foam concrete mixes. In the same line, addition of CMC to surfactant solution enhances viscosity of surfactant solution significantly and thereby results in improvement of foam microstructure, concrete air void microstructure and eventually improves compressive strength of foam concrete. Further, improved microstructure with smaller air voids in foam concrete with NPE + CMC results in 10%–25% relatively higher compressive strength than SLS + CMC foam concrete mixes.

A Profile of New Zealand Crossbred Wool Clip in Both Greasy and Scoured Forms in the 2017-18, 2018-19, and 2019-20 Seasons

ABSTRACT New Zealand is the third-largest producer of wool in the world and accounts for approximately 9.3% of world production (approx. 140,000 tonnes greasy annually). We describe the properties of the New Zealand crossbred wool clip over the 2017–18, 2018–19, and 2019–20 seasons and compare the statistics from the greasy farm lots with data obtained from consignments of scoured wool. Monthly average values of diameter, vegetable matter, and color exhibit seasonality, and despite the fact that approximately 30% of the wool is exported in its greasy state, the remaining 70% scoured onshore still adequately represents the body of the clip, with still some degree of seasonality, but with changes in the distribution of diameters of consignments (but not the overall averages), and improvements in color. Additionally, we demonstrate that despite the replacement of nonylphenolethoxylate (NPEO) by more environmental-friendly detergents, the levels of residual ash and grease in the scoured wool consignments show improvement over those reported in 2003 and 2007.