University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Phenols, chloro

@ ChemSpider@ NIST@ PubChem

Citations 6

"Preconcentration And Flow Injection Multivariate Determination Of Priority Pollutant Chlorophenols"
Anal. Chim. Acta 1995 Volume 308, Issue 1-3 Pages 238-245
F. Navarro-Villoslada, L. V. Pérez-Arribas, M. E. León-González* and L. M. Polo-Díez

Abstract: Water (500 ml) containing up to 200 ppb of chlorophenols was acidified with 10 mL 3 M HCl and passed through a XAD-4 column (1.2 g of resin; 65 mm x 5 mm i.d.) at 4 ml/min. The chlorophenols were eluted with 10 mL methanol. The eluate was evaporated to dryness and the residue was dissolved in 10 mL 0.01 M borate buffer of pH 9.1. A 250 µL portion of the solution was injected into a borate buffer carrier stream (1.5 ml/min) and merged with a 1.5 g/l tetrabutylammonium nitrate stream (1.2 ml/min). The flow passed through a reaction coil (30 cm x 0.3 mm i.d.) to allow chlorophenol-tetrabutylammonium ion-pairs to form. The ion-pairs were extracted into CHCl3 by merging with a CHCl3 stream (0.6 ml/min). After passing through the extraction coil (130 cm x 0.3 mm i.d.) the phases were separated in a membrane phase separator. The spectra of the organic phase were recorded every 0.6 s from 200-430 nm. The first derivative spectra was calculated. Calibration standards contained up to 10 mg/l of chlorophenols. Three multivariate methods were used, namely, classical least squares, partial least squares and a Kalman filter. The method was used to analyze tap water spiked with chlorophenols up to 180 µg/l. All three multivariate calibration methods gave acceptable errors (~e;5%) for each chlorophenol (listed) except 2,4,6-trichlorophenol (~e;15%).
Water Spectrophotometry Spectroscopy Sample preparation Calibration Ion pair extraction Kalman filter Organic phase detection Preconcentration Multivariate calibration Partial least squares Phase separator

"An Electrocatalytic Approach For The Measurement Of Chlorophenols"
Anal. Chim. Acta 1996 Volume 327, Issue 3 Pages 235-242
Shishan Zhao and John H. T. Luong*

Abstract: Chlorophenols were oxidized to chloroquinone by reaction with ceric sulfate or chloroperoxidase. Determination was carried out by FIA using 0.1 M phosphate buffer of pH 7 containing 40 mM glucose as the carrier solution (1 ml/min). Detection was effected with an enzyme electrode prepared by depositing a mixture of glucose oxidase and glutaraldehyde onto the surface of a vitreous C electrode. Measurements were made relative to a Ag/AgCl reference electrode. A Pt-wire electrode served as the counter electrode. The relative sensitivities of the electrode towards 19 chlorophenols were reported. Highest response was exhibited towards 2,4,6-trichlorophenol in which the detection limit was 1.5 nM. The detection limits for the other congeners ranged from 10^-20 nM.
Potentiometry Electrode

"Quenched Room Temperature Phosphorescence Detection For Flow Injection And Liquid Chromatography"
Anal. Chem. 1983 Volume 55, Issue 12 Pages 1886-1893
J. J. Donkerbroek, A. C. Veltkamp, C. Gooijer, N. H. Velthorst, and R. W. Frei

Abstract: The cited detection technique is based on quenching of the phosphorescence of biacetyl by suitable analytes. The sensitivity of such quenching is dependent on the bimolecular rate constant of the quenching reaction. Values for this constant and for the estimated limit of detection in aqueous 83.7% acetonitrile, water or hexane are listed for various chloroanilines, amines, aromatic N compounds, S-containing compounds, chlorophenols, aromatic and aliphatic hydroxy-compounds, and inorganic ions. The detection limits are often very low, e.g., 1 to 10 nM. The rectilinearity of the relationship between signal and concentration. can be extended by use of electronic signal inversion techniques. Application of this detection method to flow injection analysis and HPLC is demonstrated.
Clinical analysis HPLC Phosphorescence Quenching Review Theory

"A Reticulated Vitreous Carbon Spectroelectrochemical Detector For Flow Injection Analysis And Liquid Chromatography"
Electroanalysis 1992 Volume 4, Issue 4 Pages 487-493
Janet Weiss Sorrels, Howard D. Dewald

Abstract: The design, construction and operation are described of a spectroelectrochemical detector, with a 1 cm optical path length, that incorporates an optically transparent reticular vitreous-carbon working electrode (cf. Dewald and Wang, Anal. Chim. Acta, 1984, 166, 163) which can easily be replaced in the event of electrode fouling. In the determination of [Fe(CN)6]3- by a flow injection procedure, with spectrophotometry at 410 nm, the calibration graph was rectilinear in the range 4 to 100 µM and the limit of detection was ~2 µM. Application of the detector in LC is exemplified by the analysis of a mixture of phenol, chlorophenols and nitrophenols. A spectroelectrochemical detector for flow injection and liquid chromatography is described. The detector design has dimensions of a standard 1 cm sample cuvette with a replaceable reticulated vitreous carbon working electrode. No special cell holder or modifications to the spectrophotometer are required to use the detector. Chronocoulometry is used to indicate a trend from thin-layer behavior toward semi-infinite diffusion behavior as the electrode pore size increases. Ferro-/ferricyanide solutions were used to evaluate the flow injection characteristics of the detector. A sampling rate of 180 injections per h was used. Linear calibration curves in the micromolar range were achieved with a reproducibility of 2-7%. A mixture of phenol, chlorophenols, and nitrophenols was used to investigate the simultaneous electrochemistry and optical response for liquid chromatography
Spectroelectrochemistry Electrode Apparatus Detector

"Rhodamine Labelling Reagent For The Determination Of Chlorophenols By Liquid Chromatography With Peroxyoxalate Chemiluminescence Detection"
J. Chromatogr. A 1988 Volume 459, Issue 1 Pages 139-149
P. J. M. Kwakman, J. G. J. Mol, D. A. Kamminga, R. W. Frei, U. A. Th. Brinkman and G. J. De Jong

Abstract: The pre-column labelling procedure involved the whirl-mixing of 500 µL of a solution of chlorophenols in 0.02 M carbonate buffer (pH 9.0), 100 µL of 0.2 M tetrabutylammonium iodide in aqueous 50% acetone, and 500 µL of a 0.5 mg mL-1 solution of Lissamine Rhodamine B sulfonyl chloride (Kodak, Weesp, Netherlands) in hexane - toluene - acetonitrile (4:3:1). After further mixing with 50 µL of ~2 M propylamine, 400 µL of the organic layer was evaporated to dryness. The residue, dissolved in mobile phase, was analyzed on a column (15 cm x 3.1 mm) of LiChrosorb RP-18 (5 µm) with acetonitrile - 10 mM imidazole nitrate buffer of pH 7.0 (3:1) as mobile phase (0.5 mL min-1), or on a column (25 cm x 3.1 mm) of LiChrosorb Si 60 (5 µm) with toluene - acetonitrile - methanol (12:8:1) containing 5 mM imidazole as mobile phase (0.5 mL min-1). Post-column derivatization was performed with 10 mM bis-(2-nitrophenyl) oxalate(I) and 50 mM H2O2 in acetonitrile for the reversed-phase system, or 10 mM I in toluene - acetonitrile (3:2), and a solid-phase perhydrit reactor for the normal-phase system. Detection limits were in the low pg range. Calibration graphs were rectilinear from 5 to 500 ppb of 2,4,6-trichlorophenol.
Chemiluminescence HPLC Post-column derivatization

"Sensitive Liquid Chromatographic Determination Of Alkyl-, Nitro- And Chlorophenols By Pre-column Derivatization With Dansyl Chloride, Post-column Photolysis And Peroxyoxalate Chemiluminescence Detection"
J. Chromatogr. A 1991 Volume 553, Issue 1 Pages 345-356
P. J. M. Kwakman, D. A. Kamminga and U. A. Th. Brinkman, G. J. De Jong

Abstract: Aqueous phenol-containing solution was adjusted to pH 12 with 1 M NaOH, treated with aqueous tetrabutylammonium bromide and dansyl chloride in CH2Cl2. After mixing, a portion of the organic phase was applied to an amino-bonded SPE column and the dansyl derivatives were eluted with CH2Cl2. The eluate was evaporated to dryness and the residue was dissolved in aqueous 50% methanol. A portion of the solution was analyzed by LC on a column (20 cm x 3.2 mm) of LiChrosorb RP-18 (3 µm) with methanol - imidazole buffer of pH 7 as eluent (gradient elution details given). After chromatography, the dansyl derivatives were irradiated in a photochemical reactor (cf. Scholten et al., ibid, 1980, 199, 239) before 2-nitrophenyl oxalate - H2O2 in acetonitrile were added to the column eluate (for chemical excitation); peroxyoxalate chemiluminescence detection at 470 nm (excitation at 340 nm) was used. The method was applied to determine several phenolic compounds in surface water; detection limits were 0.01 to 0.1 ng mL-1.
Surface Chemiluminescence LC Buffer Column pH Pre-column derivatization Reactor Sensitivity Post-column derivatization