Chlorophenols extraction from water

Ion-pair extraction and IPC were combined to analyze phosphoric acid mono- and diesters originating from the microbial hydrolysis of flame retardants. Even tertiary treatment did not ensure complete removal of the studied compounds detected in municipal wastewater [107], Chlorophenols extracted from water samples as anionic chlorophenolates were studied by IPC because the anionic forms of these analytes provide better UV ultraviolet absorption than uncharged chlorophenol based on their auxochromic effects. IPC conditions yielded adequate retention of the charged analytes and good sensitivity [108]. 

The DLLME technique was introduced by Rezaee et al. and applied for extraction of polycyclic aromatic hydrocarbons (PAHs), pesticides, and alkylbenzenes [17] UV filters [18] and chlorophenols [19] from water samples. Summarized applications can be found in review articles [20-24]. An interesting concept is the introduction of ionic liquids as extractants [25-28]. 

Chlorophenol metabolites of chlorophenoxy acid herbicides were successfully extracted from water and soils by SPME. The optimization of the derivatization-SPME in water for these metabolites (among 30 phenohc compounds), showed that CW-PDMS (85 fim) was the most suitable fiber, with quantification limits ranging from 1 to 15... 

Figure 13.15 Chromatograms obtained by on-line ti ace enrichment of 50 ml of Ebro river water with and without the addition of different volumes of 10% Na2S03 solution for every 100 ml of sample (a) blank with the addition of 1000 p.1 of sulfite (b) spiked with 4 p.g 1 of the analytes and 1000 p.1 of sulfite (c) spiked with 4 p.g 1 of the analytes and 500 p.1 of sulfite (d) spiked with 4 p.g 1 of the analytes without sulfite. Peak identification is as follows 1, oxamyl 2, methomyl 3, phenol 4, 4-niti ophenol 5, 2,4-dinitrophenol 6, 2-chlorophenol 7, bentazone 8, simazine 9, MCPA 10, atrazine. Reprinted from Journal of Chromatography, A 803, N. Masque et ai, New chemically modified polymeric resin for solid-phase extraction of pesticides and phenolic compounds from water , pp. 147-155, copyright 1998, with permission from Elsevier Science.

Bekou, E., Dionysiou, D.D., Qian, R.-Y., Botsaris, G.D., Extraction of chlorophenols from water using room temperature ionic liquids, ACS Sympos. Ser., 856, 544-560,2003. 

Departing from the "conventional extraction cell design, Theibolt et al. (11) used a novel phase segmentor and subsequent phase separator in order to extract 4-chlorophenol and phenol from water. On-line SFC was used for subsequent analysis. Recoveries and reproducibilities for the system were not reported, although with a single pass system 100% recovery would not be expected. We too have demonstrated... 

Caro, E., R.M. Marce, P.S.G. Cormack, D.C. Sherrington, and F. Borrull. 2003. On-line solid-phase extraction with molecularly imprinted polymers to selectively extract substituted 4-chlorophenols and 4-nitrophenol from water. J. Chromatogr. A 995 233-238. 

Other plants such as potatoes, cauliflower, cherries, and soybeans and several fungi may also be used as sources of peroxidase enzymes. Soybeans, in particular, may represent a valuable source of peroxidase because the enzyme is found in the seed coat, which is a waste product from soybean-based industries [90]. In this case, it may be possible to use the solid waste from the soybean industry to treat the wastewaters of various chemical industries. In fact, the direct use of raw soybean hulls to accomplish the removal of phenol and 2-chlorophenol has been demonstrated [105]. However, it should be noted that this type of approach would result in an increase in the amount of solid residues that must be disposed following treatment. Peroxidases extracted from tomato and water hyacinth plants were also used to polymerize phenolic substrates [106], Actual plant roots were also used for in vivo experiments of pollutant removal. The peroxidases studied accomplished good removal of the test substrate guaiacol and the plant roots precipitated the phenolic pollutants at the roots surface. It was suggested that plant roots be used as natural immobilized enzyme systems to remove phenolic compounds from aquatic systems and soils. The direct use of plant material as an enzyme source represents a very interesting alternative to the use of purified enzymes due to its potentially lower cost. However, further studies are needed to confirm the feasibility of such a process. 

A process to separate naphthenes from paraffins is claimed in Ref. [103]. It involves the use of a polar solvent for separation in a microporous membrane device. Use of membrane extraction to remove p-nitrophenol in wastewater from dye and pesticide synthesis was investigated in Ref. [104]. Removal of nonvolatile pesticide components from water is presented in Ref. [105]. Removal of several important organic pollutants such as phenol, chlorophenol, nitrobenzene, toluene, and acrylonitrile from wastewater was investigated in Ref. [106]. 

Nitroso-4-chlorophenol and rhodamine B form a ternary complex with iron(II) which is extractable from sea water with benenzene or toluene at pH 4.7. A 20-fold... 

In the field of solid-phase extraction (SPE) methods, research is oriented toward the identification and synthesis of new sorbents with increased selectivity. It has already been shown that polar adsorbents such as Oasis HLB (vinylpyrrolidone-divinylbenzene copolymer) can isolate organophosphorous pesticides from blood or serum, or triazines, acetamides and phenoxy acids from surface and waste water. Recently, a new polymeric material, polyaniline, was introduced for the extraction of chlorophenolic pesticides in water samples. Immunosorbents produced by covalent immobilization of the antibody generated against the target analyte on... 

El-Sheikh, A.H. Al-Quse, R.W. El-Barghouthi, M.I. Al-Masri, F.S. (2010). Derivatization of 2-chlorophenol with 4-amino-anti-pyrine A novel method for improving the selectivity of molecularly imprinted solid phase extraction of 2-chlorophenol from water. Talanta, 83,667-673. 

Bagheri and Saraji [152] also employed a polymeric material, polyaniline, as a new sorbent for SPE of some environmental pollutants from water samples. In this work, chlorophenols were extracted from aqueous samples by SPE using 120 mg polyaniline and determined by GC with ECD. 

It is difficult to compare recoveries obtained by different laboratories because their extraction conditions (pH, phase ratio, number and time-length of extractions, salinity) are generally different. Sample volumes can be very high, up to 200 1 [433], and 50 1 of surface water [434] or 201 of sea water allow the extraction of 5 ng/1 of alkanes. When using a specific detection method, the sample volume can be lower 2 ng/1 of PAH was determined from 11 of river water using liquid chromatography and fluorescence detection [435]. Chlorophenols below the 10 ng/1 level were determined from 100 ml of sea water with electron capture detection (ECD) GC [436]. 

Water extraction is also occasionally combined with solid-phase microextraction. Thus Wennrich et al. [97] determined chlorophenols in soil by using accelerated water extraction to remove the chlorophenols from the soil followed by adsorption onto a solid sorbent for ten minutes at 125 °C. Low ppb detection limits were thus achieved. 

The operational performance of an HF-based ESTM technique was first described by Liu et al.71 A 15-cm piece of HF was filled with an acceptor buffer solution, after which the F1F was made into a loop. This loop-like F1F device was soaked in n-undecane, and then immersed in 1 L of a river or leachate water sample for extraction of freely dissolved chlorophenols. This FIF-loop device was also employed for selective ESTM sampling of freely available Cu+2 in leachate water.78 The selectivity stemmed from a selective liquid membrane (di-n-dihexyl ether) containing a carrier (crown ether/oleic acid) and a selective stripping agent in the acceptor solution. 

FIGURE 13.3 Hollow-fiber devices for membrane extraction (a) hollow-fiber loops for equilibrium extraction. (Reprinted from Liu, J.-F., Jonsson, J.A., and Mayer, R, Equilibrium sampling through membranes of freely dissolved chlorophenols in water samples with hollow fiber supported liquid membrane, Anal. Chem., 77, 4800. Copyright 2005 American Chemical Society.) (b) Liquid-phase microextraction device... 

To prepare the [m-(acetylpyridinio)-n-alkyl]adenosine pyrophosphates, 10 mmoles of acetylpyridinio-n-alkylphosphoric acid and 10 mmoles of adenosine 5 -phosphoromorpholidate (as salt of 4-morpholine iV,iV -dicyclohexylcarboxamidine) are dissolved in 20 ml of freshly distilled o-chlorophenol. The mixture is stored at room temperature for 7 days. Progress of the condensation reaction is checked daily by paper electrophoresis (0.1 M Tris chloride at pH 8.1, 30 V/cm). After the reaction is completed, 60 ml of water are added to the mixture and the suspension is extracted 3 times, each with 200 ml of ethyl ether. The first ether extract obtained is reextracted with 30 ml of water. The combined aqueous phases are reduced to a volume of 5 ml under reduced pressure and are charged on to a Dowex 1X8 column (formate form, 2 X 50 cm, 100-200 mesh). The column is washed with 6.5 liters of water, and the coenzyme analogs are eluted from the resin with a convex gradient of formic acid ... 

Caro et al. [155] s)mthesized three polymers using 4-chlorophenol (4-CP) as the template, following different protocols (noncovalent and semicovalent), and used different functional comonomers, 4-vinylpyridine (4-VP) and methacrylic acid (MAA). They have evaluated the selectivity of the polymers as MIPs sorbent in SPE coupled online to LC. They found out that the 4-VP noncovalent polymer was the only polymer that showed a clear imprint effect. This MIP also showed cross-reactivity for the 4-chloro-substituted phenols and for 4-NP from a mixture containing the 11 priority EPA phenolic compounds and 4-CP. The MIP was applied to selectively extract the 4-chloro-substituted compounds and 4-NP from river water samples. Figure 16.4 shows the chromatograms obtained by online MISPE with the 4-VP noncovalent 4-CP imprinted polymer of 10 mL standard solution (pH 2.5) spiked at 10 mg/L with each phenolic compoimd. 

Method II To a similar size sample, add a little water, alkalize, and extract the alkaloid quantitatively with chloroform. Wash the combined chloroform extracts, filter, and reduce volume of chloroform to about 10 ml. Add 50 ml CH3CN and titrate either potentiometrically or visually using chlorophenol red, which changes from yellow to colorless at the end point. 

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