Development of methods based on low-temperature partitioning (LTP) for monitoring cresols and chlorophenols in sewage sludge, soil, and water in column leaching.

Cresols and chlorophenols are chemical contaminants that are potentially toxic to humans and can be found in sewage sludge. These chemical contaminants can migrate into the sludge-soil-water system when sludge is used as a conditioner for agricultural soils. Thus, the objective of this study was to develop methodologies based on extraction with low-temperature partitioning (LTP) to determine cresols and chlorophenols in sewage sludge, soil, and water. The analysis was performed by gas chromatography coupled with mass spectrometry (GC-MS). The validated methods were applied to monitor cresols and chlorophenols in a column-leaching study of a sludge-soil-water system. Satisfactory results were achieved for selectivity, limit of quantification (LOQ), linearity, accuracy, and precision. In the column leaching study, only 2,4,6-trichlorophenol was quantified in sludge samples after 20 days of the experiment. None of the studied compounds were quantified in soil and leached water samples, due to the degradation promoted by the microorganisms present in the sewage sludge. Finally, validated methods were suitable for monitoring cresols and chlorophenols in the sludge-soil-water system.

Single bubble in-tube microextraction coupled with capillary electrophoresis.

Headspace (HS) extraction is a sample pretreatment technique for volatile and semivolatile organic compounds in a complex matrix. Recently, in-tube microextraction (ITME) coupled with CE using an acceptor plug placed in the capillary inlet was developed as a simple but powerful HS extraction method. Here, we present single bubble (SB) ITME using a bubble hanging to the capillary inlet immersed in a sample donor solution as a HS of submicroliter volume (∼200 nL). The analytes evaporated to the bubble were extracted into the acceptor phase through the capillary opening, then electrophoresis of the enriched extract was carried out. Since the bubble volume was much smaller than a conventional HS volume (∼1 mL), it was filled with the evaporated analytes rapidly and the analytes could be enriched much faster compared to conventional HS-ITME. Owing to the high surface-to-volume ratio of the SB, 5 min SB-ITME yielded the enrichment factor values similar to those of 10 min HS-ITME. When 5 min SB-ITME at room temperature was applied to a tap water sample, the enrichment factors of 2,4,6-trichlorophenol (TCP), 2,3,6-TCP, and 2,6-dichlorophenol were 53, 41, and 60, respectively, and the LOQs obtained by monitoring the absorbance at 214 nm were 5.6-8.3 ppb, much lower than 200 ppb, the World Health Organization guideline for the maximum permissible concentration of 2,4,6-TCP in drinking water.

Modified activated carbon derived from chestnut oak shells as a new sorbent for the needle-trap extraction.

In this study, an acid-treated-activated carbon was prepared from chestnut oak shell carbonization followed by modification with hydrochloric acid/nitric acid and then used as a new sorbent for headspace needle-trap extraction of chlorophenol compounds from aqueous solutions. Different techniques, including scanning electron microscopy, nitrogen adsorption-desorption analysis, and Fourier transform-infrared spectroscopy were used for the characterization of the sorbents. The effects of some experimental parameters, including the temperature, pH, sorbent amount, and time of extraction were optimized. The developed method is fast and sensitive, providing low and sub ng/L detection limits. The limits of detection and quantification were in the range of 0.75-5 and 5-15 ng/ml, respectively, and the equilibrium time was 20 min. Wide linearity in the range of 15-2000 ng/L with R2  > 0.9993 was obtained. Repeatability of the method was accessed at 50, 100, and 200 ng/L concentration levels and RSD% of 5%-12% was achieved. The introduced method was applied for analyzing real water samples containing spiked chlorophenols, and the relative recovery values were found to be in the range of 84%-99% at the concentration levels of 50, 100 and 200 ng/L.

Magnetic solid-phase extraction using polydopamine-coated magnetic multiwalled carbon nanotube composites coupled with high performance liquid chromatography for the determination of chlorophenols.

Polydopamine (PDA)-coated magnetic multiwalled carbon nanotube (M-MWCNT) composites were synthesized in two facile preparation steps, and were used as adsorbents for magnetic solid-phase extraction (MSPE) coupled with high-performance liquid chromatography (HPLC) for simultaneous extraction, enrichment and determination of five kinds of typical chlorophenols (CPs) in water samples. The as-prepared magnetic composites showed excellent magnetic properties and high thermal stability. Various main parameters influencing the extraction efficiency of MSPE were systematically investigated. Under the optimized MSPE-HPLC conditions, a high enrichment factor (EF) was obtained in the range of 85-112 for 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), 2,6-dichlorophenol (2,6-DCP), 2,4-dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP). Good linearity was obtained in the range of 2.0-200 µg L-1 for 2-CP and 4-CP and 1.0-200 µg L-1 for 2,6-DCP, 2,4-DCP and 2,4,6-TCP, with a correlation coefficient (R2) higher than 0.9964. The limits of detection (LODs) and the limits of quantification (LOQs) were in the range of 0.10-0.31 µg L-1 and 0.35-1.03 µg L-1, respectively. The intraday and interday precisions evaluated using relative standard deviation (RSD) values were in the range of 1.05-2.25% and 1.88-2.83%, respectively. The validated MSPE-HPLC method was also successfully applied to analyze five kinds of CPs in tap water, lake water, river water and seawater samples, and satisfactory recoveries were obtained in the range of 76.87-106.5% with RSDs of 1.64-6.78%.

Bikini textile contact dermatitis: A Sherlockian approach revealing 2,4-dichlorophenol as a potential textile contact allergen.

BACKGROUND: Different textile constituents may act as allergens and/or irritants and provoke textile contact dermatitis (TCD). OBJECTIVES: To report a case of TCD caused by ethylene glycol monododecyl ether and 2,4-dichlorophenol, present in a bikini. METHODS: A woman presented with an eczematous, pruritic rash in the area of the bikini straps and back. Patch testing was performed with the European baseline, textile, sunscreen, and photo-patch series, the bikini "as is", and ethanol and acetone extracts of the bikini. Thin-layer chromatography (TLC) of the extracts and gas chromatography-mass spectrometry (GC-MS) analysis were used to elucidate the culprit agents. RESULTS: Positive reactions were found to the bikini "as is" and to the ethanol and acetone extracts. Patch testing with TLC strips showed a strong reaction to spots-fractions 3 and 4. GC-MS was performed to identify substances in each fraction and those suspected to be skin sensitisers were patch tested. On day (D) 4 positive reactions to ethylene glycol monododecyl ether (irritant reaction) and 2,4-dichlorophenol (++) were observed. CONCLUSION: A myriad of chemical compounds can be found in clothing. Ethylene glycol monododecyl ether and 2,4-dichlorophenol were identified as the potential culprits of this bikini TCD.

Tailoring of bismuth vanadate impregnated on molybdenum/graphene oxide sheets for sensitive detection of environmental pollutants 2, 4, 6 trichlorophenol.

In the present work, we reported a one pot simple colloidal-gel synthesis of molybdenum bismuth vanadate (MoBiVO4). The charge transfer property of MoBiVO4 was improved by developing a composite with graphene oxide (GO) through sonochemical technique. The optical and morphological analysis revealed that successful formation of GO-MoBiVO4 composite without any other filth. As prepared composite was used to modify the superficial surface of glassy carbon electrode (GO-MoBiVO4/GCE) and applied for the selective detection of environmental pollutant 2, 4, 6 trichrlorophenol (TCP). The electron channeling capability of GO with molybdenum bismuth vanadate possessed a superior electrochemical response in cyclic voltammetry (CV), whereas bare GCE and other modified electrodes provided an inferior response with lower current response. The differential pulse voltammetry (DPV) response of TCP at GO-MoBiVO4/GCE outcomes with low level detection of 0.4 nM and higher sensitivity of 2.49 µA µM-1 cm-2 with wider linear response 0.199-17.83 µM. Furthermore, the proposed sensor applied in practicability analysis and the results indicates GO-MoBiVO4/GCE prominent towards electrochemical detection of TCP.

Wood preservatives in children's wooden toys from China: Distribution, migration, oral exposure, and risk assessment.

A total of 90 wooden toys were collected, and six wood preservatives (chlorophenols and lindane) were analyzed by using gas chromatography-tandem mass spectrometry to assess the exposure risk of children to wood preservatives through oral contact with wooden toys. The detection rates of six preservatives ranged from 2.2% to 22.2%. The contents of the preservatives ranged from 0.6 µg/kg to 9.6 µg/kg. 2,4-Dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP) had higher detection rates and contents than other preservatives. Thus, their migration behaviors from toys to saliva were further investigated. In 11 positive samples, the max migration ratios of 2,4-DCP and 2,4,6-TCP ranged from 7.1% to 20.3% and from 11.1% to 24.8%, respectively. For children aged 3-36 months, the daily average 2,4-DCP exposure level associated with wooden toys ranged from 2.7 pg/(kg day) to 46.9 pg/(kg day), and the daily average 2,4,6-TCP exposure ranged from 3.6 pg/(kg day) to 69.4 pg/(kg day). The contribution to exposure provided by the saliva mobilization pathway was more than that provided by the ingestion of scraped-off toys, and the exposure level of 2,4,6-TCP was greater than that of 2,4-DCP. The max hazard quotient for 2,4-DCP was 1.9 × 10-4, and the max cancer risk for 2,4,6-TCP was 1.2 × 10-9. The above results indicated that although wood preservatives were distributed in wooden toys, exposure arising from directly mouthing these materials currently does not pose unacceptable risks to children.

An eco-friendly low-temperature synthetic approach towards micro-pebble-structured GO@SrTiO3 nanocomposites for the detection of 2,4,6-trichlorophenol in environmental samples.

The low-temperature synthesis of the graphene oxide-wrapped perovskite-type strontium titanate nanocomposites (GO@SrTiO3-NC) is reported for the electrochemical sensing of organochlorine pesticide 2,4,6-trichlorophenol (TCP) detection. The as-prepared GO@SrTiO3 nanocomposites provide a large surface area, excellent conductivity, and active sites, which are more favorable to the catalysis of TCP. The synergistic effect between the GO and the perovskite SrTiO3 results in the extended working range of 0.01 to 1.47 and 1.47 to 434.4 µM with a very low detection limit of 3.21 nM towards TCP detection. Moreover, the prepared sensor possessed good selectivity and long-term stability. Finally, the practical applicability of the sensor was tested in environmental samples of river water and soil, exhibiting adequate recovery values.

Fabrication of carbonyl-functional hypercrosslinked polymers as solid-phase extraction sorbent for enrichment of chlorophenols from water, honey and beverage samples.

Three carbonyl-functional novel hypercrosslinked polymers (HCP-TPS, HCP-TPA, and HCP-TPP) were successfully fabricated through an one-step Friedel-Crafts acylation reaction by copolymerizing paraphthaloyl chloride with triphenylsilane, triphenylamine, and triphenylphosphine, respectively. The resultant HCPs contained plenty of carbonyl-functional groups. Among the series of such HCPs, HCP-TPS displayed the best adsorption capability to chlorophenols (CPs), and thus it was employed as solid-phase extraction (SPE) adsorbent for enrichment of chlorophenols from water, honey, and white peach beverage prior to determination by high-performance liquid chromatography. Under the optimal conditions, the detection limits of the method (S/N = 3) were 0.15-0.3 ng mL-1 for tap water and leak water, 2.5-6.0 ng g-1 for honey sample and 0.4-0.6 ng mL-1 for white peach beverage sample. The recoveries of CPs in the spiked water, honey samples, and white peach beverage were in the range of 89.0-108.4%, 81.4-118.2%, and 85.0-113.5%, respectively. This work provides a new strategy for constructing functionalized HCPs as efficient SPE adsorbents. In this work, three novel hypercrosslinked polymers (HCPs) were synthesized by the Friedel-Crafts alkylation reaction (paraphthaloyl chloride as the alkylating agent, triphenylsilane, triphenylamine, and triphenylphosphine as the aromatic units). Then, HCP-TPS was applied to soild-phase extraction sorbent for enrichment CPs from water, honey, and white peach beverage samples.

Monitoring of priority pollutants chlorophenols in water and milk by headspace solid-phase microextraction based on electrospun polycaprolactam nanofibers decorated with cadmium oxide-carbon nanotubes.

Priority pollutants chlorophenols are broadly used chemicals that are persistent in the environment and causing serious human health hazards. The current study introduces a novel adsorbent for the extraction of chlorophenols from river water, surface water, and milk by headspace solid-phase microextraction coupled with gas chromatography. The adsorbent composite was prepared by blending polycaprolactam (nylon-6) mat and newly synthesized carbon nanotubes decorated with cadmium oxide nanoparticles followed by electrospinning technique to produce based nanofiber. The proposed nanofiber was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction techniques. The main parameters that affect extraction efficiency, including ionic strength, extraction time, desorption time, and extraction temperature, were investigated and optimized. The linear range was 0.05-5 ng/mL; the limits of detection (signal/noise=3) were 0.02-0.04 ng/mL. The relative recoveries for real samples (river water, surface water, and milk) were in the range of 84-114%.

Effect of transient pH variation on microbial activity and physical characteristics of aerobic granules treating 4-chlorophenol.

Chlorophenols are inhibitory compounds that can be biodegraded by aerobic granules in discontinuous processes. Many industrial wastewaters are characterized by transient pH variation over time. These pH changes could affect the overall granule structure and microbial activity during the chlorophenol biodegradation. The objective of this research was to evaluate the effects of transient pH variation on the specific degradation rate (q), granule integrity coefficient (IC), and size in sequencing batch reactors treating 4-chlorophenol (4-CP). First, aerobic granules were acclimated for efficient 4-CP degradation (>99%). The acclimated granules consisted of 55.7% of the phyla Proteobacteria and 40.6% of Bacteroidetes. The main bacteria belong to the order Sphingobacteriales (24%), as well as Amaricoccus, Acidovorax, Shinella, Rhizobium, and Flavobacterium, some of which are new genera reported in acclimated granules degrading 4-CP. Then, pH changes were applied to the acclimated aerobic granules, observing that acid pHs decreased to a greater extent the specific degradation rate (67% to 99%) than basic pHs (34% to 80%). These pH changes caused the granule disaggregation but with lower effects on the IC. The effects of pH change were mainly on the microbial activity more than the physical characteristics of aerobic granules degrading 4-CP.

Comparative time-based intermediates study of ozone oxidation of 4-chloro- and 4-nitrophenols followed by LCMS-TOF.

Greater insights on the degradation pathways and intermediates formed during the oxidation of organics can be achieved by more suitable and compatible instrumentation. In our research, we sought to explore the relative advantages of the liquid chromatography coupled to a time of flight mass spectrometer (LCMS-TOF) technique for the comparative time-based degradation intermediates and pathways of 4-chlorophenol (4CP) and 4-nitrophenol (4NP). The ozonation of the analytes solution (100 mL of 2 x 10-3 M) was done in a sintered glass reactor, with an ozone dose of 0.14 mg min-1 (O2/O3 10 mL/min). The comparative oxidation results revealed that the 4-chloro- and 4-nitrocatechol pathways via hydroxylation were the major degradation route for 4CP and 4NP. Catechol intermediate was present as a primary breakdown product for the two analytes. Hydroquinone was observed as transient degradation intermediate for 4CP, but was absent for 4NP. Rather, a novel ozonation intermediate 2, 4-dinitrophenol was identified which was further oxidized to 3,6-dinitrocatechol. Several dimer products were identified in the oxidation processes, favored by alkaline conditions with more versatility shown by 4CP. The study provided a great insight into the ozone degradation intermediates and pathways, with some intermediates scarce in literature identified.

Field-amplified sample injection combined with capillary electrophoresis for the simultaneous determination of five chlorophenols in water samples.

A sensitive method of CZE-ultraviolet (UV) detection based on the on-line preconcentration strategy of field-amplified sample injection (FASI) was developed for the simultaneous determination of five kinds of chlorophenols (CPs) namely 4-chlorophenol (4-CP), 2-chlorophenol (2-CP), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and 2,6-dichlorophenol (2,6-DCP) in water samples. Several parameters affecting CZE and FASI conditions were systematically investigated. Under the optimal conditions, sensitivity enhancement factors for 4-CP, 2-CP, 2,4-DCP, 2,4,6-TCP, and 2,6-DCP were 9, 27, 35, 43, and 43 folds, respectively, compared with the direct CZE, and the baseline separation was achieved within 5 min. Then, the developed FASI-CZE-UV method was applied to tap and lake water samples for the five CPs determination. The LODs (S/N = 3) were 0.0018-0.019 µg/mL and 0.0089-0.029 µg/mL in tap water and lake water, respectively. The values of LOQs in tap water (0.006-0.0074 µg/mL) were much lower than the maximum permissible concentrations of 2,4,6-TCP, 2,4-DCP, and 2-CP in drinking water stipulated by World Health Organization (WHO) namely 0.3, 0.04, and 0.01 µg/mL, respectively, and thereby the method was suitable to detect the CPs according to WHO guidelines. Furthermore, the method attained high recoveries in the range of 83.0-119.0% at three spiking levels of five CPs in the two types of water samples, with relative standard deviations of 0.37-8.58%. The developed method was proved to be a simple, sensitive, highly automated, and efficient alternative to CPs determination in real water samples.

Migration regularity of six preservatives from wooden children's products to saliva and sweat based on microstructure-related migration models.

Wood preservatives in wooden children's products (WCPs) may migrate into children's body through oral and dermal exposure, resulting in a potential health risk. In this paper, a systematic investigation on the migration regularity of lindane and five chlorophenols preservatives from WCPs to saliva and sweat was introduced. Migration models were established based on the abundant migration data among different time periods (2 min-96 h). Wood exhibited complex porosity for various species, resulting in the deviation of the migration of preservatives from different samples. By introducing a correction coefficient (f) calculated based on the sample microstructure (specific surface area and pore distribution), the predicted values of correcting migration model matched better with the experimental data. Migration data indicated that exposure risks should be noticed when children were in contact with WCPs because a considerable quantity of preservatives migrated into the body in a short time. This work is expected to play a role in the formulation of chemical limit standards to promote the safety of WCPs, and may serve ideas as basis for the migration research of chemicals in wooden products.

Novel fluorescent sensor using molecularly imprinted silica microsphere-coated CdSe@CdS quantum dots and its application in the detection of 2,4,6-trichlorophenol from environmental water samples.

In this study, a high fluorescence sensitivity and selectivity, molecularly imprinted nanofluorescent polymer sensor (MIP@SiO2 @QDs) was prepared using a reverse microemulsion method. 2,4,6-Trichlorophenol (2,4,6-TCP) was detected using fluorescence quenching. Tetraethyl orthosilicate (TEOS), quantum dots (QDs) and 3-aminopropyltriethoxysilane (APTS) were used as cross-linker, signal sources and functional monomer respectively. The sensor (MIP@SiO2 @QDs) and the non-imprinted polymer sensor (NIP@SiO2 @QDs) were characterized using infra-red (IR) analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The selectivity of MIP@SiO2 @QDs was examined by comparing 2,4,6-TCP with other similar functional substances including 2,4-dichlorophenol (2,4-DCP), 2,6-dichlorophenol (2,6-DCP) and 4-chlorophenol (4-CP). Results showed that MIP@SiO2 @QDs had better selectivity for 2,4,6-TCP than the other compounds. Fluorescence quenching efficiency displayed a good linear response at the 2,4,6-TCP concentration range 5-1000 µmol/L. The limit of detection (LOD) was 0.9 µmol/L (3σ, n = 9). This method was equally applicable for testing actual samples with a recovery rate of 98.0-105.8%. The sensor had advantages of simple pretreatment, good sensitivity and selectivity, and wide linear range and could be applied for the rapid detection of 2,4,6-TCP in actual samples.

Electronic Tongue Coupled to an Electrochemical Flow Reactor for Emerging Organic Contaminants Real Time Monitoring.

Triclosan, which is a bacteriostatic used in household items, has raised health concerns, because it might lead to antimicrobial resistance and endocrine disorders in organisms. The detection, identification, and monitoring of triclosan and its by-products (methyl triclosan, 2,4-Dichlorophenol and 2,4,6-Trichlorophenol) are a growing need in order to update current water treatments and enable the continuous supervision of the contamination plume. This work presents a customized electronic tongue prototype coupled to an electrochemical flow reactor, which aims to access the monitoring of triclosan and its derivative by-products in a real secondary effluent. An electronic tongue device, based on impedance measurements and polyethylenimine/poly(sodium 4-styrenesulfonate) layer-by-layer and TiO2, ZnO and TiO2/ZnO sputtering thin films, was developed and tested to track analyte degradation and allow for analyte detection and semi-quantification. A degradation pathway trend was observable by means of principal component analysis, being the sample separation, according to sampling time, explained by 77% the total variance in the first two components. A semi-quantitative electronic tongue was attained for triclosan and methyl-triclosan. For 2,4-Dichlorophenol and 2,4,6-Trichlorophenol, the best results were achieved with only a single sensor. Finally, working as multi-analyte quantification devices, the electronic tongues could provide information regarding the degradation kinetic and concentrations ranges in a dynamic removal treatment.

Effects of 4-chlorophenol toxicity on sludge performance and microbial community in sequencing batch reactors.

In this study, the effects of 4-chlorophenol (4-CP) influent concentrations ranging from 10 to 100 mg L-1 on sludge toxicity, enzymatic activity and microbial community, along with their correlations, were investigated in a sequencing batch bioreactor (SBR), which was defined as the acclimated SBR. Another SBR was set as a control group that did not receive the influent 4-CP. The results showed that the sludge toxicity increased as the influent 4-CP increased, exhibiting a positive correlation with 4-CP loads. The enzymatic activity was stimulated after long-term acclimation with 4-CP and was positively related to the 4-CP loads and sludge toxicity. During the stable operational stages of the acclimated SBR, the microbial diversity first increased and then decreased as the 4-CP loads increased, while the similarity of the microbial community between the acclimated and control SBRs decreased with increasing 4-CP loads. The aim of this study is to provide theoretical support for reducing sludge toxicity in industrial wastewater treatment.

Fate of the organophosphorus pesticide profenofos in cotton fiber.

Pesticides carried by cotton fiber are potential risk for production workers and consumers. Dissipation behaviour of a commonly used cotton pesticide profenofos in cotton fiber during growing period and scouring treatment was investigated. The results showed that profenofos in the fiber from the pre-opened and post-opened bolls both decreased to undetectable amounts 21 days after pesticide application. However, a minority of profenofos was converted to a strongly irritant compound, 4-bromo-2-chlorophenol and retained a non-negligible amount in cotton fiber even after 28 days. Profenofos and its degradation product could be completely removed during the conventional cotton scouring process. The degradation half-time of profenofos in scouring bath was only 3.0 min, and the degradation product was also 4-bromo-2-chlorophenol. Cotton products made of profenofos-carrying fiber are safe; however, the scouring waste should be detoxicated before discharge due to the accumulation of 4-bromo-2-chlorophenol in the scouring bath. These results could be useful for evaluating the risk of cotton fiber from the profenofos applied fields.

One-step preparation of polyimide-inlaid amine-rich porous organic block copolymer for efficient removal of chlorophenols from aqueous solution.

A novel polyimide-inlaid amine-rich porous organic block copolymer (PI-b-ARPOP) was prepared via one-step polymerization by using different molar ratios of melamine (MA)/terephthalaldehyde (TA)/pyromellitic dianhydride (PMDA), at molar ratios of 4/3/1, 4/2/2 and 4/1/3. The copolymer contained both aminal groups belonging to ARPOP and imide groups belonging to PI, and the bonding styles of the monomers and growth orientations of the polymeric chains were diversiform, forming an excellent porous structure. Notably, MA/TA/PMDA (4/2/2) had a surface area and pore volume of 487.27 m2/g and 1.169 cm3/g, respectively. The adsorption performance of the materials towards 2,4-dichlorophenol (2,4-DCP) in ultra-pure water was systematically studied. The pH value of 7 was optimal in aqueous solution. Na+ and Cl- ions did not negatively affect the adsorption process, while humic acid (HA) slightly decreased the capacity. The equilibrium time was 40 sec, and the maximum adsorption capacity reached 282.49 mg/g at 298 K. The removal process was endothermic and spontaneous, and the copolymer could maintain its porous structure and consistent performance after regeneration by treatment with alkali. Moreover, to further assess the practical applicability of the material, the adsorption performance towards 2,4-DCP in river water was also investigated. This paper demonstrated that the PI-b-ARPOP can be an efficient and practical adsorbent to remove chlorophenols from aqueous solution.

Dispersive liquid-liquid microextraction of five chlorophenols in water samples followed by determination using capillary electrophoresis.

Dispersive liquid-liquid microextraction (DLLME) coupled with CE was developed for simultaneous determination of five types of chlorophenols (CPs), namely 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), 2,4-dichlorophenol (2,4-DCP), 2,6-dichlorophenol (2,6-DCP), and 2,4,6-trichlorophenol (2,4,6-TCP) in water samples. Several parameters affecting DLLME and CE conditions were systematically investigated. Under the optimized DLLME-CE conditions, the five CPs were separated completely within 7.5 min and good enrichment factors were obtained of 40, 193, 102, 15, and 107 for 4-CP, 2,4,6-TCP, 2,4-DCP, 2-CP, and 2,6-DCP, respectively. Good linearity was attained in the range of 1-200 µg/L for 2,4,6-TCP, 2,4-DCP, 2-300 µg/L for 4-CP and 2-CP, and 1-300 µg/L for 2,6-DCP, with correlation coefficients (r) over 0.99. The LOD (S/N = 3) and the LOQ (S/N = 10) were 0.31-0.75 µg/L and 1.01-2.43 µg/L, respectively. Recoveries ranging from 60.85 to 112.36% were obtained with tap, lake, and river water spiked at three concentration levels and the RSDs (for n = 3) were 1.31-11.38%. With the characteristics of simplicity, cost-saving, and environmental friendliness, the developed DLLME-CE method proved to be potentially applicable for the rapid, sensitive, and simultaneous determination of trace CPs in complicated water samples.