Determination Of Chlorophenols In Water Research Articles

Sustainable and green synthesis of porous organic polymer for solid-phase extraction of four chlorophenols in water and honey

A novel hypercrosslinked polymer (API-HCP) was synthesized using as monomer for the first time. API-HCP exhibited high adsorption affinity toward chlorophenols due to the hydrogen bond, halogen bond and π-stacking interactions. With API-HCP as adsorbent, an efficient solid phase extraction method coupled with high performance liquid chromatography (SPE-HPLC) was established for the sensitive detection of chlorophenols in water and honey samples. Under the optimum conditions, the method provided a good linear response in the range of 0.07–100 ng mL−1 for water and 1.7–500 ng g−1 for honey sample. High sensitivity was achieved, with detection limits (S/N = 3) of 0.02–0.07 ng mL−1 for water and 0.5–1.5 ng g−1 for honey samples. The method recoveries for spiked sample were between 84.0 % and 116.0 %, with relative standard deviations ≤6.1 %. The API-HCP based SPE-HPLC method provided a robust platform for sensitive determination of chlorophenols in water and honey samples.

Determination of chlorophenols in water by liquid chromatography method after magnetic solid phase extraction based on SiO2/MIL‐101@Fe3O4 nanoadsorbent

AbstractLiquid chromatographic determination of chlorophenols in water and wastewater samples was performed following magnetic solid phase extraction based on SiO2/MIL (Materials Institute Lavoisier)‐101@Fe3O4 nanoadsorbent. To the best of our knowledge, there is no report on the synthesis and application of SiO2/MIL‐101@Fe3O4 for enrichment and extraction of chlorophenols. The nanoadsorbent was characterized by scanning electron microscopy, transmission electron microscopy, Fourier Transform infrared spectroscopy, and vibrating sample magnetometry. One variable at a time and central composite design were used for optimization. The optimum conditions were achieved as following: pH value, 4.7; sample volume, 40 mL; nanoadsorbent amount, 25.0 mg; adsorption time, 3.5 min sonication; salt concentration, 10% w/v NaCl; eluent volume, 140 µL 0.01 mol/L HCl in methanol. After optimization, linearity was attained in the range of 0.2‐300 µg L−1 (r2 > 0.9978) and limits of detection were 0.06‐0.2 µg L−1. Method precision as relative standard deviation was less than 6.7% and enrichment factors were achieved in the range of 134–189. The proposed method based on using SiO2/MIL‐101@Fe3O4 nanoadsorbent is simple and fast owing to the magnetically‐assisted separation. Finally, the method was employed for the analysis of mineral water and wastewater samples with satisfactory results (recovery, 89–103%; relative standard deviation, 5.0–7.9%).

Determination of chlorophenols in water using dispersive liquid-liquid microextraction coupled with water-in-oil microemulsion electrokinetic chromatography in normal stacking mode.

The current routes to couple dispersive liquid-liquid microextraction with capillary electrophoresis are the evaporation of water immiscible extractants and the back-extraction of analytes. In this study, a new methodology for this combination using water-in-oil microemulsion electrokinetic chromatography coupled with normal stacking mode on-line sample concentration was developed to analyze chlorophenols in water samples. The analytes were extracted with tributyl phosphate and the extractant dilution (3×) was directly injected into an electrophoresis buffer (7.7cm) containing 5% sodium dodecyl sulfate, 78% 1-butanol, 2% 1-heptane, and 15% sodium acetate solution (pH 8.0). This proposed method is very simple and convenient compared to the conventional procedures. The key parameters affecting separation and concentration were systematically optimized. Under the optimized conditions, dispersive liquid-liquid microextraction contributed an enrichment factor of 45-50, and the overall sensitivity improvement was 312-418-fold. Limits of detection between 1.4 and 3.0ng/mL and limits of quantification between 4.5 and 10.2ng/mL were achieved. Acceptable repeatability lower than 3.0% for migration time and 9.0% for peak areas were obtained. The developed method was successfully applied for analysis of the chlorophenols in real water samples.

Efficient removal and trace determination of chlorophenols from water using mixed hemi-/ad-micelle ionic liquid-coated magnetic graphene oxide and the adsorption mechanism

Solid phase extraction based on magnetic graphene oxide nanoparticles and 1-hexadecyl-3-methylimidazolium bromide is used for the removal and determination of chlorophenols in water.

Hollow fiber liquid–liquid–liquid microextraction followed by solid-phase microextraction and in situ derivatization for the determination of chlorophenols by gas chromatography-electron capture detection

A method based on the combination of hollow fiber liquid–liquid–liquid microextraction and solid-phase microextraction (SPME) followed by gas chromatography-electron capture detection was developed for the determination of chlorophenols in water and wastewater samples. Silica microstructures fabricated on the surface of a stainless steel wire were coated by an organic solvent and used as a SPME fiber. The analytes were extracted through a hollow fiber membrane containing n-decane from sample solution to an alkaline aqueous acceptor phase. They were then extracted and in situ derivatized on the SPME fiber using acetic anhydride. Experimental parameters such as the type of extraction solvent, acceptor phase NaOH concentration, donor phase HCl concentration, the amount of derivatizing reagent, salt concentration, stirring rate and extraction time were investigated and optimized. The precision of the method for the analytes at 0.02–30μgL−1 concentration level ranged from 7.1 to 10.2% (as intra-day relative standard deviation) and 6.4 to 9.8% (as inter-day relative standard deviation). The linear dynamic ranges were in the interval of 5–500μgL−1, 0.05–5μgL−1, 0.02–1μgL−1 and 0.001–0.5μgL−1 for 2-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol, respectively. The enrichment factors were between 432 and 785. The limits of detection were in the range of 0.0004–1.2μgL−1. Tap water, well water and wastewater samples were also analyzed to evaluate the method capability for real sample analysis.

Ultrasound‐Assisted Emulsification‐Microextraction With In Situ Derivatization and Gas Chromatography‐Electron‐Capture Detection for Determination of Chlorophenols in Water

A new method, ultrasound‐assisted emulsification–microextraction (USAEME) with in situ derivatization and gas chromatography‐electron‐capture (GC‐μ‐ECD) detection, was developed to determine selected chlorophenols (CPs), including 2‐chlorophenol, 2,6‐dichlorophenol, 2,4,5‐trichlorophenol, 2,3,4,6‐tetrachlorophenol, and pentachlorophenol in water and wastewater samples. Initially the suitable solvent was determined and amount of derivatization reagent (acetic anhydride) and K2CO3, other experimental variables involving extraction and derivatization time, volume of extraction solvent and sample ionic strength, were optimized employing a 23 factorial experimental design. The developed method employed 100 μL of chloroform as extraction solvent, extraction with in situ derivatization for 10 min using 100 µL of acetic anhydride and 100 µL K2CO3 (5%, w/v) for 5 mL samples at 25°C with no ionic strength adjustment and centrifugation for 5 min at 4000 rpm. The average relative recoveries under optimum conditions were >97% with relative standard deviation (RSD) ≤5% for three different spiking levels (5, 20, and 100 μg L‐1). The limits of detection for studied CPs were in the range of 0.007–0.011 μg L−1. The developed USAEME with in situ derivatization method was successfully applied to real water samples such as tap, dam water, and domestic wastewater. The developed method showed comparable efficiency with conventional liquid–liquid extraction‐derivatization coupled with GC‐μ‐ECD. The results demonstrated that the developed USAEME with in situ derivatization is simple, fast and reliable for determination of selected CPs in water samples by GC‐μ‐ECD.

Development of a solid‐phase microextraction fiber coated with poly(methacrylic acid‐ethylene glycol dimethacrylate) and its application for the determination of chlorophenols in water coupled with GC

A solid-phase microextraction (SPME) fiber coated with poly(methacrylic acid-ethylene glycol dimethacrylate) coupled to GC with a micro electron-capture detector was developed for the determination of four chlorphenols in water samples for the first time. A novel and simple method for the preparation of this novel SPME fiber was proposed by copolymerization of methacrylic acid and ethylene glycol dimethacrylate in an appropriate solvent using a glass capillary as a "mold". The factors affecting the polymerization were optimized in detail. Furthermore, the extraction performance of the poly(methacrylic acid-ethylene glycol dimethacrylate) fiber was evaluated. Moreover, experimental headspace-SPME parameters, such as extraction temperature, extraction time, salt concentration, stirring speed, and pH, were optimized by orthogonal array experimental designs. Under the optimized conditions, the target analytes were linear in the range of 0.2-50 ng/mL, and the correlation coefficients were all greater than 0.99. RSD was less than 8.9%, and the detection limits were in the range of 0.1-10 ng/L. Four cholorphenols were detected from tap and lake water samples using the proposed method, with the recoveries of spiked natural water samples were ranged from 91.8 to 110.8, and 90.6 to 111.4% for tap and lake water samples, respectively.

Determination of chlorophenols in water by headspace solid phase microextraction ion mobility spectrometry (HS-SPME-IMS)

Chlorophenols (CPs) as persistent toxic compounds are of worldwide environmental concern. Usage of chlorinated phenols, especially pentachlorophenol (PCP), has been restricted or widely banned in many countries due to their possible adverse health effects even at low concentrations. Ion mobility spectrometry (IMS) has received increasing interest in environmental applications due to its unique characteristics, such as portability and speed of analysis. A range of sample introduction methods combined with IMS enable analysis from different environmental matrices. This study utilised headspace solid phase microextraction IMS (HS-SPME-IMS) in the determination of CPs from water samples. The extraction conditions were examined and the method was applied to real water samples. The developed method is suitable to detect CPs at milligram per liter level in water. Based on the results, SPME-IMS setup is feasible as an early warning system for water monitoring of pollutants present in drinking or surface water in case of environmental accidents or leakages.

HPLC Determination of Chlorophenols in Water with Separation by Ionic Liquids [Bmim]BF4 Aqueous Two-phase Solvent Sublation

HPLC Determination of Chlorophenols in Water with Separation by Ionic Liquids [Bmim]BF4 Aqueous Two-phase Solvent Sublation

Full automatic determination of chlorophenols in water using solid‐phase microextraction/on‐fiber derivatization and gas chromatography‐mass spectrometry

A fully automated combination of solid-phase microextraction and on-fiber derivatization coupled with gas chromatography-mass spectrometry was developed to determine 17 chlorophenols in aqueous samples. Optimal parameters for the automated process, such as fiber coating (polyacrylate), derivatization reagent (N,O-bis(trimethylsilyl) trifluoroacetamide), extraction time (60 min), derivatization time (5 min), incubation temperature (35°C), sample pH (3), and ionic strength (300 g L(-1) of NaCl), as well as desorption time (5 min) and desorption temperature (270°C) were established. The whole procedure took only 90 min and was performed automatically. The shortcomings of silylation derivatives, like incompleteness and instability, were overcome by using solid-phase microextraction on-fiber silylation in this study. The results from both pure water and river water samples showed that the method had a good linearity (r(2) = 0.9993-1.0000), ranging from 0.01 to 100 μg L(-1). The related standard deviations were between 3.6 and 10.0%. The limits of detections and qualifications ranged from 0.03 to 3.11 ng L(-1) and 0.09 to 10.4 ng L(-1) for the CPs, respectively. The proposed method is superior to traditional solid phase extraction procedure.

Faster and simpler determination of chlorophenols in water by fiber introduction mass spectrometry

Solid phase microextraction (SPME) of chlorophenols [2-chlorophenol (2CP), 2,4-dichlorophenol (24CP), 4-chloro-3-methylphenol (43CP), 2,4,6-tri-chlorophenol (246CP) and pentachlorophenol (PCP)] followed by direct mass spectrometric analysis has been performed by fiber introduction mass spectrometry (FIMS). Two SPME fibers (65 μm PDMS/DVB and 85 μm PA fibers) were tested, and FIMS was performed via selective ion monitoring (SIM). The extractions were evaluated at 10% ionic strength and pH 1. Best extraction times were determined for both fibers. Limits of detection (LOD) and limits of quantification (LOQ) for both fibers were in the low μg L −1 range. Coefficients of correlation for the analytical curves showed linear responses and mineral water and river water samples spiked with 50 μg L −1 presented high recoveries. FIMS, as compared to current EPA methods, is demonstrated to allow faster and simpler (elimination of pre-separation or derivatization steps) analysis of chlorophenols in water with the required sensitivity.

Application of liquid–liquid–liquid microextraction and ion-pair liquid chromatography coupled with photodiode array detection for the determination of chlorophenols in water

A method termed as liquid–liquid–liquid microextraction was utilized to extract chlorophenols from water. The extracted chlorophenols, present in anionic form, were then separated, identified, and quantitated by ion-pair high-performance liquid chromatography with photodiode array detection (HPLC/DAD). For trace chlorophenol determination using HPLC/DAD, the chlorophenolate anion provides a better ultraviolet spectrum for quantitative and qualitative analyses than does uncharged chlorophenol. This is due to the auxochromic effect of the phenolate anion. In the study, experimental conditions such as organic phase identity, acceptor phase volume, sample agitation, extraction time, acceptor phase NaOH concentration, donor phase HCl concentration, salt addition, and UV absorption wavelength were optimized. Relative standard deviations (RSD, 2.3–5.4%), coefficients of determination ( r 2 0.9994–0.9999), and detection limits (0.049–0.081 ng mL −1) of the proposed method were investigated under the selected conditions. The method was successfully applied to analyses of reservoir and tap water samples, and the relative recoveries of chlorophenols from the spiked reservoir and tap water samples were 94.1–100.4% and 87.8–101.2%, respectively. The proposed method is capable of identifying and quantitating each analyte to 0.5 ng mL −1, confirming the HPLC/DAD technique to be quite robust for monitoring trace levels of chlorophenols in water samples.

Development of a solid-phase microextraction method with micellar desorption for the determination of chlorophenols in water samples: Comparison with conventional solid-phase microextraction method

A novel analytical method is presented for the determination of chlorophenols in water. This method involves pre-concentration by solid-phase microextraction (SPME) and an external desorption using a micellar medium as desorbing agent. Final analysis of the selected chlorophenols compounds was carried out by high-performance liquid chromatography (HPLC) with diode array detection (DAD). Optimum conditions for desorption, using the non-ionic surfactant polyoxyethylene 10 lauryl ether (POLE), such as surfactant concentration and time were studied. A satisfactory reproducibility for the extraction of target compounds, between 6 and 15%, was obtained, and detection limits were in the range of 1.1–5.9 ng mL −1. The developed method is evaluated and compared with the conventional one using organic solvent as a desorbing agent. The method was successfully applied to the determination of chlorophenols in water samples from different origin. This study has demonstrated that solid-phase microextraction with micellar desorption (SPME-MD) can be used as an alternative to conventional SPME method for the extraction of chlorophenols in water samples.

In‐capillary solid‐phase extraction–capillary electrophoresis for the determination of chlorophenols in water

A novel CE method combined with SPE in a single capillary was developed for analysis of chlorophenols in water. A frit of 0.5 mm was first made by a sol-gel method, followed by packing a SPE sorbent in the inlet end of the capillary. Two phenol derivatives, 2,4-dichlorophenol and 2,4,5-trichlorophenol, were used as the model compounds. By loading sample solutions into the capillary, the two chlorophenols were extracted into the sorbent. They were desorbed by injecting only about 4 nL of methanol. Finally, the analytes were separated by conventional CE. The technique provided a concentration enhancement factor of over 4000-fold for both chlorophenols. The detection limits (S/N = 3) of 2,4-dichlorophenol and 2,4,5-trichlorophenol were determined to be 0.1 ng/mL and 0.07 ng/mL, respectively. For replicate analyses of 5 ng/mL of 2,4-dichlorophenol, within-day and between-day RSDs of migration time, peak height and peak area were in the range of 1.8-2.0%, 4.0-4.4% and 4.1-4.6%, respectively. The method shows wide linear range, acceptable reproducibility and excellent sensitivity, and it was applied to the analyses of spiked river water samples. The capillary packed with the SPE sorbents can be used for more than 400 runs without performance deterioration.

Vial position in the determination of chlorophenols in water by solid phase microextraction

The extraction of chlorophenol from water by headspace solid phase microextraction (HS-SPME) in vials located both vertically and horizontally is compared. The results obtained show that kinetic parameters are clearly affected by how the vial is placed in the analysis of semivolatile compounds. Extraction time for reach the equilibrium was three times lower in the horizontal configuration. An on-line extraction unit coupled to a continuous flow system is used to analyse unmodified ground water samples. In order to increase the high throughput, the analysis time is reduced and the sensitivity increased by making the extraction simultaneously with two fibres. The proposed method is applied to the analysis of spiked river water samples. The precision expressed as relative standard deviation ranges from 3.5 to 4.8%, and the recoveries from 94 to 105%.

Stir bar sorptive extraction with in situ derivatization and thermal desorption–gas chromatography–mass spectrometry for determination of chlorophenols in water and body fluid samples

A new method, stir bar sorptive extraction (SBSE) with in situ derivatization and thermal desorption (TD)–gas chromatography–mass spectrometry (GC–MS), which is used for the determination of trace amounts of chlorophenols, such as 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TrCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) and pentachlorophenol (PCP), in tap water, river water and human urine samples, is described. The derivatization conditions with acetic acid anhydride and the SBSE conditions such as extraction time are investigated. Then, the stir bar is subjected to TD followed by GC–MS. The detection limits of the chlorophenols in tap water, river water and human urine samples are 1–2, 1–2, and 10–20 pg ml −1 (ppt), respectively. The calibration curves for the chlorophenols are linear and have correlation coefficients higher than 0.99. The average recoveries of the chlorophenols in all the samples are higher than 95% (R.S.D. < 10%) with correction using added surrogate standards, 2,4-dichlorophenol-d 5, 2,4,6-trichlorophenol- 13C 6, 2,3,4,6-tetrachlorophenol- 13C 6 and pentachlorophenol- 13C 6. This simple, accurate, sensitive and selective analytical method may be applicable to the determination of trace amounts of chlorophenols in liquid samples.

Improved determination of chlorophenols in water by solid-phase microextraction followed by benzoylation and gas chromatography with electron capture detection

A rapid method for the determination of chlorophenols in drinking water by solid-phase microextraction and gas chromatography with electron capture detection was developed and validated. A fused silica fiber coated with a 65 μm thick stationary phase of poly (dimethylsilox-ane)/divinylbenzene was used to extract chlorophenols after performingin situ derivatisation with pentafluorobenzoyl chloride in the polymeric coating. Validation was carried out in terms of limits of detection (LOD), limits of quantitation (LOQ), linearity and precision.In situ derivatisation and the choice of a fiber with more affinity towards the derivatised analytes gave LODs in the 0.005–0.8 μgL−1 range which are lower values than those reported in previous work using poly(dimethylsiloxane) or poly(acrylate) fibers. Linearity was statistically verified over one order of magnitude for each compound. The production of chlorophenols as disinfection by-products in the treatment of drinking water with chlorine was studied over a period of eight days: mono-, di-and trichlorophenols were detected and quantitated.

Determination of chlorophenols by solid-phase microextraction and liquid chromatography with electrochemical detection

A solid-phase microextraction method has been developed for the determination of 19 chlorophenols (CPs) in environmental samples. The analytical procedure involves direct sampling of CPs from water using solid-phase microextraction (SPME) and determination by liquid chromatography with electrochemical detection (LC–ED). Three kinds of fibre [50 μm carbowax-templated resin (CW-TPR), 60 μm polydimethylsiloxane–divinylbenzene (PDMS–DVB) and 85 μm polyacrylate (PA)] were evaluated for the analysis of CPs. Of these fibres, CW-TPR is the most suitable for the determination of CPs in water. Optimal conditions for both desorption and absorption SPME processes, such as composition of the desorption solvent (water–acetonitrile–methanol, 20:30:50) and desorption time (5 min), extraction time (50 min) and temperature (40 °C) as well as pH (3.5) and ionic strength (6 g NaCl) were established. The precision of the SPME–LC–ED method gave relative standard deviations (RSDs) of between 4 and 11%. The method was linear over three to four orders of magnitude and the detection limits, from 3 to 8 ng l −1, were lower than the European Community legislation limits for drinking water. The method was applied to the analysis of CPs in drinking water and wood samples.

Multi- and univariate interpretation of the interlaboratory validation of PrEN 12673; GC determination of chlorophenols in water

In order to validate the (preliminary) CEN method PrEN 12673 “Water quality – Gas Chromatographic determination of some selected chlorophenols in water” an interlaboratory study was organised. The intercomparison study comprised a total of nine samples; a high-level, a low-level and a blank sample of three types of water; drinking water, surface water and waste water. The level of the spikes were based on the water quality objectives. The variation in the samples due to homogeneity and stability of the components was tested extensively and appeared to be negligible in comparison with variation between the results of the participants. Results were received from 24 laboratories from eight European countries. In this data set about 7% of the data were detected as statistical outliers and were subsequently rejected. For the remaining data set the relative standard deviations for repeatability varied between 5% and 25% and reproducibility between 26% and 56%. Both these ranges complied with the general variation in interlaboratory studies as found by Horwitz. The recovery of the spikes found by the participants generally varied between 60% and 140%. The data set was also evaluated for differences in results due to the degrees of freedom in the standard method. The largest difference was found between participants who perform internal versus external calibration. The latter method obtained results that were on average up to 50% lower than the results of the participants applying internal standards. Another degree of freedom in the standard method that should be evaluated was the use of a mass spectrometer (MS) instead of an electron capture detector (ECD). The MS results varied, among the components, between minus 25% and plus 20% compared to the ECD results. The result of the interlab study was compiled into one large data set to enable a multivariate evaluation. Since only alternative selections of the chlorophenols were added to each of the samples, this data set contained a lot of missing values (>50%). A least squares procedure was implemented to estimate the PCA-like results iteratively showing a prominent first principle component that describes about 40% of total variance with all loadings on the same side. This indicated that a major multi-component systematic source of variation was present at a number of laboratories.

Determination of chlorophenols in water by direct acetylation and solid-phase extraction

Determination par chromatographie en phase gazeuse avec detecteur a ionisation de flamme ou a capture d'electrons