Why do ammonium salt/phenol-based deep eutectic solvents show low viscosity?

The viscosity of deep eutectic solvents (DESs) plays an important role in determining how they are used industrially. In order to gain a deeper insight into the parameters which affect the viscosity of ionic DES, a series of systems composed of ammonium salts and two types of representative donors were prepared and characterized. They were investigated by quantum-chemistry calculations and molecular dynamics simulations. The viscosity of phenol/4-methylphenol-based system is much lower than that of glycolic acid-based system. Moreover, DESs containing glycolic acid exhibit higher activation energy values compared with DESs containing phenolics. It was found the existence of a strong charge transfer complex between glycolic acid and ammonium salt, thus suggesting its vital role in the fluidity difference of studied mixtures. The hydrogen bonds of glycolic acid-based system are partially covalent and partially electrostatic, manifested via atoms in molecules (AIM) analysis. Additionally, Cl^??HO_{phenolic hydroxyl} is expected to be less covalent than Cl^??HO_carboxyl, which is also identified by lower delocalization index in the AIM basin. The interaction network stability of glycolic acid-based DES is more robust than that of phenolics-based one due to the strong covalency of hydrogen bond. This is the main reason that ammonium salt/phenol-based DESs show low viscosity. This work gives new perspectives on more rational design of novel DES with low viscosity.     

Usage of deep eutectic solvents for the digestion and ultrasound-assisted liquid phase microextraction of copper in liver samples

In this study, we used deep eutectic solvents for digestion and ultrasound-assisted emulsification liquid phase microextraction (UA-ELPME) of copper in liver samples. Different types of DESs were prepared for digestion and microextraction steps. DESs consisting of lactic acid and choline chloride for the digestion step and DESs consisting of tetrabuthylamonium chloride and decanoic acid for ultrasound-assisted emulsification liquid phase microextraction were used in this method. The liver samples were digested by using DES-based digestion method. After digestion step, Cu(II) ions in aqueous phase were complexed with sodium dimethyl dithiocarbamate (NaDMDTC) and the obtained hydrophobic complex was extracted to tetrabuthylamonium chloride-decanoic acid DES phase. A microsample injection system coupled with flame atomic absorption spectrometer (MS-FAAS) was used in the detection of copper. LOD, LOQ, PF and % RSD were determined as 4.00, 13.2 µg L^??1, 10 and 3.2%, respectively. The proposed microextraction procedure was successfully applied to copper contents of the liver samples.     

Preparation of Magnesium,Cobalt and Nickel Ferrite Nanoparticles from Metal Oxides using Deep Eutectic Solvents

Natural deep eutectic solvents (DESs) dissolve simple metal oxides and are used as a reaction medium to synthesize spinel‐type ferrite nanoparticles MFe₂O₄ (M=Mg, Zn, Co, Ni). The best results for phase‐pure spinel ferrites are obtained with the DES consisting of choline chloride (ChCl) and maleic acid. By employing DESs, the reactions proceed at much lower temperatures than usual for the respective solid‐phase reactions of the metal oxides and at the same temperatures as synthesis with comparable calcination processes using metal salts. The method therefore reduces the overall required energy for the nanoparticle synthesis. Thermogravimetric analysis shows that the thermolysis process of the eutectic melts in air occurs in one major step. The phase‐pure spinel‐type ferrite particles are thoroughly characterized by X‐ray diffraction, diffuse‐reflectance UV/Vis spectroscopy, and scanning electron microscopy. The properties of the obtained nanoparticles are shown to be comparable to those obtained by other methods, illustrating the potential of natural DESs for processing metal oxides.     

Hydrated‐Metal‐Halide‐Based Deep‐Eutectic‐Solvent‐Mediated NiFe Layered Double Hydroxide: An Excellent Electrocatalyst for Urea Electrolysis and Water Splitting

The liquid structures of deep eutectic solvents (DESs) based on hydrated metal halides and their application as electrolytes have been widely studied. However, little attention has been paid to the direct use of this type of DES in the preparation of micro‐/nanomaterials. Herein, an FeCl₃ ? 6 H₂O/urea DES was used in the one‐step synthesis of NiFe‐LDH_D with a nanoflower morphology. In alkaline media, this catalyst promoted excellent electrocatalytic activity for the oxidation of urea at potential of 1.32 V (vs. RHE) and for the oxygen‐evolution reaction at a potential of 1.39 V to achieve a current density of 10 mA cm^?2. These results were superior to the results with NiFe‐LDH/NF that was obtained from an aqueous solution of FeCl₃, as well as most of the previously reported transition‐metal catalysts. Furthermore, NiFe‐LDH_D/NF could be readily implemented as both a cathode and an anode for the electrolysis of urea and water splitting. The use of hydrated‐metal‐halide‐based DESs for the preparation of LDH catalysts through a dipping‐redox strategy should both enrich the research of DESs and offer guidance for the rational surface engineering of catalysts for the electrolysis of urea and overall water splitting with high performance.     

Mixed Conductive,Injectable, and Fluorescent Supramolecular Eutectogel Composites

Eutectogels are an emerging family of soft ionic materials alternative to ionic liquid gels and organogels, offering fresh perspectives for designing functional dynamic platforms in water-free environments. Herein, the first example of mixed ionic and electronic conducting supramolecular eutectogel composites is reported. A fluorescent glutamic acid-derived low-molecular-weight gelator (LMWG) was found to self-assemble into nanofibrillar networks in deep eutectic solvents (DES)/poly(3,4-ethylenedioxythiophene) (PEDOT): chondroitin sulfate dispersions. These dynamic materials displayed excellent injectability and self-healing properties, high ionic conductivity (up to 10⁻² S cm⁻¹), good biocompatibility, and fluorescence imaging ability. This set of features turns the mixed conducting supramolecular eutectogels into promising adaptive materials for bioimaging and electrostimulation applications.     

Ice as Solid Electrolyte To Conduct Various Kinds of Ions

Water, considered as a universal solvent to dissolve salts, has been extensively studied as liquid electrolyte in electrochemical devices. The water/ice phase transition at around 0 °C presents a common phenomenon in nature, however, the chemical and electrochemical behaviors of ice have rarely been studied. Herein, we discovered that the ice phase provides efficient ionic transport channels and therefore can be applied as generalized solid‐state ionic conductor. Solid state ionic conducting ices (ICIs) of Li⁺, Na⁺, Mg²⁺, Al³⁺, K⁺, Mn²⁺, Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺, and Zn²⁺, frozen from corresponding sulphate solutions, exhibit ionic conductivities ranging from ≈10^?7 S cm^?1 (Zn²⁺) to ≈10^?3 S cm^?1 (Li⁺) at temperatures spanning from ?20 °C to ?5 °C. The discovery of ICIs opens new insight to design and fabrication of solid‐state electrolytes that are simple, inexpensive, and versatile.     

己内酰胺基酸性低共熔剂对柴油的氧化脱硫:低共熔剂组成与催化反应活性（英文）

汽车尾气中硫化物的排放所导致的酸雨和PM2.5等环境污染问题广受关注.各个国家和地区也相继制定了严格的标准来控制柴油中的含硫量.加氢脱硫工艺成熟,但是需要在高温高压下进行,并且柴油中二苯并噻吩及其衍生物的位阻效应使得加氢脱硫难以将其脱除.氧化脱硫作为加氢脱硫的补充技术,以其反应条件温和等优点成为脱硫研究的重要课题.作为离子液体类似物,低共熔剂不仅具有离子液体的优点,而且无毒、生物可降解、价格低廉,且制备过程简单,是一种绿色溶剂.低共熔剂作为萃取剂和催化剂用于柴油的氧化脱硫中,展现出非常好的应用前景.尽管在低共熔剂氧化脱硫体系中氢键发挥着重要的作用,但是关于低共熔剂组成,氢键强度与氧化脱硫反应活性三者之间关系的探究相对缺乏.本文以己内酰胺和草酸为原料,调节二者配比制备了一系列己内酰胺基低共熔剂.通过差示扫描量热法、傅里叶变换红外光谱、核磁共振氢谱以及热重分析对制备的低共熔剂进行表征,从而确定组成与氢键之间的关系.将制备的低共熔剂应用于氧化脱硫体系中,发现氧化脱硫率随着低共熔剂组成的变化而规律变化.此外,系统地研究了影响氧化脱硫效率的反应参数.结果表明,在优化的反应条件下,己内酰胺基酸性低共熔剂的脱硫率可以达到98%.该反应体系下,三种不同硫化物的脱除率按照以下顺序依次递减:二苯并噻吩4,6-二甲基二苯并噻吩苯并噻吩.实验数据与表征结果表明,在低共熔剂氧化脱硫体系中氢键相互作用影响脱硫效率,而氢键相互作用则可以通过调节低共熔剂的组成来改变.该结果为了解柴油深度脱硫机理提供了新的思路.     

A novel deep eutectic solvent-based ionic liquid used as electrolyte for dye-sensitized solar cells

We utilize a quaternary ammonium salt-derivative ionic liquid called G.CI which is a eutectic mixture of glycerol and choline iodide as electrolyte for dye-sensitized solar cells. Such eutectic compound belongs to a new series of ionic liquid called deep eutectic solvents (DES), which possess many outstanding features compared to the traditional imidazolium-based ionic liquids including cheap raw materials, simple preparation procedures and better biocompatibility. Current–voltage characteristics of the G.CI/PMII-based binary electrolytes stand at 0.533 V on V_oc, 12.0 mA cm^?2 on J_sc, 0.582 on fill factor, and 3.88% cell efficiency under AM 1.5, 100 mW/cm² illuminations. The comparable cell performance together with all the above advantages makes G.CI as a strong candidate for future electrolyte development for dye-sensitized solar cells (DSSCs).     

Isolation of Ferulic Acid from Wheat Bran with a Deep Eutectic Solvent and Modified Silica Gel

Five deep eutectic solvents (DESs) were synthesized with choline chloride and glycerol at ratios from 1:1 to 1:5 and used to extract ferulic acid from wheat bran. The DES with choline chloride:glycerol at a 1:2 molar ratio (DES-2) provided the highest extraction yield. The optimal extraction conditions for DES-2 were obtained using response surface methodology with a yield of 5.86?mg?·?g^?1 ferulic acid. The DES-2 was used to modify silica gel and purify ferulic acid from wheat bran by solid-phase extraction (SPE). The yields were compared for silica gel and silica gel modified with ionic liquid. The recoveries for ferulic acid were 64.1, 89.7, and 80.3%, respectively. Silica gel modified with DES-2 provided the highest recovery. The materials were characterized by infrared spectroscopy and scanning electron microscopy. The DESs were used as extraction solvents and to modify silica gel for SPE, expanding their use in the isolation of ferulic acid from wheat bran.     

Magnetic molecularly imprinted polymers based on silica modified by deep eutectic solvents for the rapid simultaneous magnetic‐based solid‐phase extraction of Salvia miltiorrhiza bunge,Glycine max (Linn.) Merr and green tea

Novel magnetic molecularly imprinted polymers (MMIPs) with multiple‐template based on silica were modified by four types of deep eutectic solvents (DESs) for the rapid simultaneous magnetic solid‐phase extraction (MSPE) of tanshinone Ⅰ, tanshinone ⅡA, and cryptotanshinone from Salvia miltiorrhiza bunge; glycitein, genistein, and daidzein from Glycine max (Linn.) Merr; and epicatechin, epigallocatechin gallate, and epicatechin gallate from green tea, respectively. The synthesized materials were characterized by Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Single factor experiments were to explore the relationship between the extraction efficiency and four factors (the sample solution pH, amount of DESs for modification, amount of adsorbent, and extraction time). It was showed that the DES4‐MMIPs have better extraction ability than the MMIPs without DESs and the other three DESs‐modified MMIPs. The best extraction recoveries with DES4‐MMIP were tanshinone Ⅰ (85.57%), tanshinone ⅡA (80.58%), cryptotanshinone (92.12%), glycitein (81.65%), genistein (87.72%), daidzein (92.24%), epicatechin (86.43%), epigallocatechin gallate (80.92%), and epicatechin gallate (93.64%), respectively. The novel multiple‐template MMIPs materials modified by DES for the rapid simultaneous MSPE of active compounds were proved to reduce the experimental steps than single‐template technique, and increase the extraction efficiency.     

Cyclic Voltammetry of Metallic Acetylacetonate Salts in Quaternary Ammonium and Phosphonium Based Deep Eutectic Solvents

Seven commercially sourced acetylacetonate salts were investigated in deep eutectic solvents (DESs that were prepared from ethylene glycol and trifluoroacetamide hydrogen bond donors) by cyclic voltammetry, to identify electrolytes suitable for future applications in electrochemical energy storage devices. Although the solubilities are low and on the order of 0.02 mol·L^?1 for the most soluble salts, some were found to display encouraging quasi-reversible electrochemical kinetics. For instance, the diffusion coefficients of copper(II) acetylacetonate and iron(III) acetylacetonate in the trifluoroacetamide based DES are 1.14 × 10^?8 and 5.12 × 10^?9 cm²·s^?1, which yields rate constants of 3.16 × 10^?3 and 8.43 × 10^?6 cm·s^?1, respectively. These results are better than those obtained with the DESs prepared from ethylene glycol. The poor kinetics of the iron(III) acetylacetonate system was possibly due to the hygroscopic nature of the DESs that resulted in a continuous build-up of moisture in the system in spite of the maintenance of an inert atmosphere by means of a plastic glove bag. Further work is thus envisaged in an inert dry box that could lead to H-type glass cell charge/discharge experiments in the future.     

Frontal Polymerization of Deep Eutectic Solvents Composed of Acrylic and Methacrylic Acids

Frontal polymerization of deep eutectic solvents (DESs) made with acrylic or methacrylic acid as the monomer and hydrogen bond donor was studied. Fronts with acrylic acid and choline chloride propagated more uniformly than with pure acrylic acid, so an exploration into how the DES affected frontal polymerization was performed. The hydrogen bond acceptor of the DES was replaced by several analogs to determine the effect on the DES front behavior. The analogs used were talc, DMSO, lauric acid, and stearic acid, which acted as a heat sink, inert diluent, hydrogen bonding diluent, and inert phase change material, respectively. None of the methacrylic acid‐analog systems were able to sustain a front. While the acrylic acid‐analog systems did sustain a front (with the exception of stearic acid), none of the fronts replicated the acrylic acid DES behavior. The acrylic acid–talc sample behaved more violently—like pure acrylic acid polymerization—than the acrylic acid DES, and the DMSO and lauric acid samples produced slower fronts than that of the acrylic acid DES. We propose that the reactivity of the acrylic acid and methacrylic acid is enhanced in the DES. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 4046–4050     

Efficient Extraction of Fermentation Inhibitors by Means of Green Hydrophobic Deep Eutectic Solvents

The methods for hydrogen yield efficiency improvements, the gaseous stream purification in gaseous biofuels generation, and the biomass pretreatment are considered as the main trends in research devoted to gaseous biofuel production. The environmental aspect related to the liquid stream purification arises. Moreover, the management of post-fermentation broth with the application of various biorefining techniques gains importance. Chemical compounds occurring in the exhausted liquid phase after biomass pretreatment and subsequent dark and photo fermentation processes are considered as value-added by products. The most valuable are furfural (FF), 5-hydroxymethylfurfural (HMF), and levulinic acid (LA). Enriching their solutions can be carried with the application of liquid–liquid extraction with the use of a suitable solvent. In these studies, hydrophobic deep eutectic solvents (DESs) were tested as extractants. The screening of 56 DESs was carried out using the Conductor-like Screening Model for Real Solvents (COSMO-RS). DESs which exposed the highest inhibitory effect on fermentation and negligible water solubility were prepared. The LA, FF, and HMF were analyzed using FT-IR and NMR spectroscopy. In addition, the basic physicochemical properties of DES were carefully studied. In the second part of the paper, deep eutectic solvents were used for the extraction of FF, LA, and HMF from post-fermentation broth (PFB). The main extraction parameters, i.e., temperature, pH, and DES: PFB volume ratio (V_DES:V_PFB), were optimized by means of a Box–Behnken design model. Two approaches have been proposed for extraction process. In the first approach, DES was used as a solvent. In the second, one of the DES components was added to the sample, and DES was generated in situ. To enhance the post-fermentation broth management, optimization of the parameters promoting HMF, FF, and LA extraction was carried under real conditions. Moreover, the antimicrobial effect of the extraction of FF, HMF, and LA was investigated to define the possibility of simultaneous separation of microbial parts and denatured peptides via precipitation.     

Evaluation of green and efficient deep eutectic solvents as media for extracting alkaloids from lotus leaf

Deep eutectic solvents (DESs) were applied as eco-friendly solvents in this study for the extraction of alkaloids from lotus leaf, including O-nornuciferine, N-nornuciferine, nuciferine and roemerine. A series of hydrophilic and hydrophobic DESs with different hydrogen bond donors and a acceptors were synthesized and screened for a suitable DESs for extraction of alkaloids from lotus leaf. The study results showed that the hydrophilic DES with choline chloride and propanediol had the highest extraction yield. The main factors affecting the extraction efficiency—choline chloride–propanediol ratio, water content in deep eutectic solvents, solid–liquid ratio and extraction time—were investigated via a single-factor experiment. The optimized extraction conditions were 30% of water in choline chloride–propanediol (1:4) for heated extraction for 30 min and solid–liquid ratio 1:100 g/ml. Under optimum conditions, the extraction yields of O-nornuciferine, N-nornuciferine, nuciferine and roemerine were 0.069, 0.152, 0.334 and 0.041 g/100 g respectively, which were higher than those of methanol in acidified aqueous solution. This study suggests considerable potential for DESs as promising materials for the green and efficient extraction solvents for bioactive alkaloids from natural sources.     

A novel vortex-assisted liquid phase microextraction method for parabens in cosmetic oil products using deep eutectic solvent

ABSTRACT

The parabens, which are harmful to our bodies, are primarily utilized as preservatives in medicine, personal care products and cosmetics. A novel, more efficient, fast and cheap vortex-assisted liquid phase microextraction method based on deep eutectic solvents (DESs) was developed for the determination of parabens. The microextraction conditions were optimized using these solvents and the analytical parameters of the method were determined under optimal microextraction conditions. After extraction, the chromatographic separation of parabens was undertaken using high-performance liquid chromatography-UV detection. Experimental parameters, such as DES type, DES volume, dilution solvent volume and vortex extraction time were optimized. DES6 [ChCl-Ethylene glycol (1/2)] was the most suitable DES to work in this study. Detection limits for this method of 0.053 µg mL^?1 for methylparaben, 0.061 µg mL^?1 for ethylparaben, 0.049 µg mL^?1 for propylparaben and 0.052 µg mL^?1 for butylparaben were obtained. Correlation coefficients (R²) for a concentration range of 0.1–100 µg mL^?1 were higher than 0.9992 and relative standard deviation (RSD) values below 2.91% at parabens concentration of 2.5 µg mL^?1 were obtained. The results of spike/recovery values of real samples were greater than 84%. When compared with other methods, the main advantages include lower LOD, short extraction time, rapidity, repeatability and simplicity.     

Chemoselective synthesis of xanthenes and tetraketones in a choline chloride-based deep eutectic solvent

A chemoselective synthesis of tetraketone and xanthene derivatives, by means of tandem Knoevenagel condensation and Michael addition in choline chloride-based deep eutectic solvents (DESs), is presented. The reaction of readily available aldehydes and active methylene compounds in malonic acid- and ZnCl₂-based DES gives various xanthenes derivatives with good to excellent yields under mild reaction conditions. On the other hand, tetraketones were synthesized in almost quantitative yields by simple condensation of an aldehyde and active methylene compounds in milder deep eutectic solvents of urea and SnCl₂. In addition, the reaction of other types of choline chloride-based DES leads to a mixture of tetraketone and xanthene.     

Application of Deep Eutectic Solvents in the Synthesis of Substituted 2-Mercaptoquinazolin-4(3H)-Ones: A Comparison of Selected Green Chemistry Methods

In this study, deep eutectic solvents (DESs) were used as green and eco-friendly media for the synthesis of substituted 2-mercaptoquinazolin-4(3H)-ones from different anthranilic acids and aliphatic or aromatic isothiocyanates. A model reaction on anthranilic acid and phenyl isothiocyanate was performed in 20 choline chloride-based DESs at 80 °C to find the best solvent. Based on the product yield, choline chloride:urea (1:2) DES was found to be the most effective, while DESs acted both as solvents and catalysts. Desired compounds were prepared with moderate to good yields using stirring, microwave-assisted, and ultrasound-assisted synthesis. Significantly, higher yields were obtained with mixing and ultrasonication (16–76%), while microwave-induced synthesis showed lower effectiveness (13–49%). The specific contribution of this research is the use of DESs in combination with the above-mentioned green techniques for the synthesis of a wide range of derivatives. The structures of the synthesized compounds were confirmed by ¹H and ¹³C NMR spectroscopy.     

A Comprehensive Study of CO2 Absorption and Desorption by Choline-Chloride/Levulinic-Acid-Based Deep Eutectic Solvents

Amine absorption (or amine scrubbing) is currently the most established method for CO₂ capture; however, it has environmental shortcomings and is energy-intensive. Deep eutectic solvents (DESs) are an interesting alternative to conventional amines. Due to their biodegradability, lower toxicity and lower prices, DESs are considered to be “more benign” absorbents for CO₂ capture than ionic liquids. In this work, the CO₂ absorption capacity of choline-chloride/levulinic-acid-based (ChCl:LvAc) DESs was measured at different temperatures, pressures and stirring speeds using a vapour–liquid equilibrium rig. DES regeneration was performed using a heat treatment method. The DES compositions studied had ChCl:LvAc molar ratios of 1:2 and 1:3 and water contents of 0, 2.5 and 5 mol%. The experimental results showed that the CO₂ absorption capacity of the ChCl:LvAc DESs is strongly affected by the operating pressure and stirring speed, moderately affected by the temperature and minimally affected by the hydrogen bond acceptor (HBA):hydrogen bond donator (HBD) molar ratio as well as water content. Thermodynamic properties for CO₂ absorption were calculated from the experimental data. The regeneration of the DESs was performed at different temperatures, with the optimal regeneration temperature estimated to be 80 °C. The DESs exhibited good recyclability and moderate CO₂/N₂ selectivity.     

An effective approach to enhanced thermoelectric properties of PEDOT:PSS films by a DES post‐treatment

As conventional organic solvents present inherent toxicity, deep eutectic solvents (DES) have been considered as excellent candidates due to their green characteristics. In this work, thermoelectric properties enhancement of PEDOT:PSS films is achieved by introducing DES as an additive and post‐treatment reagent. Direct addition and post‐treatment approaches lead to a maximum Seebeck coefficient of 29.1 μV K^?1 and electrical conductivity of 620.6 S cm^?1, respectively. In addition, an optimal power factor is obtained by DES post‐treatment, reaching up to 24.08 μW m^?1 K^?2, which is approximately four orders of magnitude higher than the pure PEDOT:PSS. Assuming a thermal conductivity of 0.17 W m^?1 K^?1, the maximum ZT value is estimated to be 0.042 at 300 K. Further, atomic force microscopy and X‐ray photoelectron spectroscopy are performed and suggest that the remarkably enhanced electrical conductivity originates from the removal of the excess insulating PSS and the phase separation between the PEDOT and PSS chains. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 885–892     

Preconcentration and Determination of Chlorophenols in Wastewater with Dispersive Liquid–Liquid Microextraction Using Hydrophobic Deep Eutectic Solvents

Abstract

Hydrophobic deep eutectic solvents (DESs) were synthesized and developed for the preconcentration of three chlorophenols from wastewater by dispersive liquid–liquid microextraction (DLLME). The analyte concentrations were determined by high-performance liquid chromatography (HPLC). The hydrophobic DESs were prepared with the combination of hydrogen bond donors of decanoic acid or octanoic acid with different hydrogen bond acceptors of quaternary ammonium salts of tetrabutylammonium chloride, tetraoctylammonium chloride, methyltrioctylammonium chloride, and tetraheptylammonium chloride). Following the study of the stability and characterization by Fourier transform infrared spectroscopy, the hydrophobic DESs were developed as extractants and employed for the removal of 4-chlorophenol (4-CP), 2,4-dichlorophenol (2,4-DCP), and 2,4,6-trichlorophenol (2,4,6-TCP) from wastewater. Using hydrophobic DESs as the microextraction solvents, several key parameters were optimized, including the type and volume of the hydrophobic DES, pH, and time of the extraction procedure. Under the optimized conditions, good recoveries from 90.8% to 93.0% were obtained for the three chlorophenols. The limits of detection were less than 0.05?µg/mL with relative standard deviations between 1.8% and 3.1%. The method was applied for the isolation and determination of synthetic chlorophenols in wastewater.