Multicomponent Determination of Chlorinated Hydrocarbons Using a Reaction-Based Chemical Sensor. 1. Multivariate Calibration of Fujiwara Reaction Products

An in situ method for the determination of trichloroethylene (TCE), perchloroethylene (PCE), chloroform (CHCl3), and carbon tetrachloride (CCl4) in aqueous solution is described. The method is based on ESERS—a combination of electrochemical methods and surface-enhanced Raman scattering (SERS). Electrochemistry prepares the surface of a copper electrode for SERS and concentrates the analyte on the surface. The formation of common reaction products for chloroalkanes and for chloroalkenes prevents unequivocal differentiation within a specific class of chlorinated hydrocarbons. However, spectroscopic selectivity between the chloroalkane and chloroalkene classes is excellent, while differences in electrochemical response provide a secondary means for differentiating analyte class. Sensitivity was found to be: <1 ppm for TCE; 15 ppm for PCE; 15 ppm for CHCl3; and 10 ppm for CCl4. Application of the method to groundwater contaminated with TCE has been demonstrated. In combination with a fiber-optic waveguide, the ESERS technique offers potential for remote detection of chlorinated hydrocarbons in groundwater and remediation process streams.

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Rapid Quantitative Vatside Check Test For Chlorinated Hydrocarbons in Aqueous Emulsions: Toxaphene and Lindane

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/48.2.334 ◽

1965 ◽

Vol 48 (2) ◽

pp. 334-338

Author(s):

Fred P Czech

Keyword(s):

Organic Solvent ◽

Field Test ◽

Chlorinated Hydrocarbons ◽

Reaction Products ◽

Special Equipment ◽

Field Worker ◽

Organic Halogen ◽

Alcohol Solvent ◽

Check Test

Abstract A simple and rapid field test is described for the vatside determination of toxaphene and lindane in aqueous emulsions used for the eradication of ectoparasites in livestock. With appropriate modification, the test should also be useful for aqueous emulsions of other chlorinated hydrocarbons. The chlorinated hydrocarbon is “salted-out” of emulsion and extracted into an organic solvent, and the extract is reacted with sodium biphenyl, which strips the molecule of organic halogen. After solution of reaction products in a glycol-alcohol solvent and adjustment of pH, the resultant chloride is titrated with silver nitrate to a pink end point with 2″,7″-dichlorofluorescein. All procedures except extraction are carried out in one vessel and there is no need for special equipment. A field worker can perform an analysis in 15 minutes.

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Leather. Determination of chlorinated hydrocarbons in leather. Chromatographic method for short-chain chlorinated paraffins (SCCP)

10.3403/30262093 ◽

2015 ◽

Keyword(s):

Chromatographic Method ◽

Chlorinated Hydrocarbons ◽

Short Chain ◽

Chlorinated Paraffins

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APPLICATION OF MULTIVARIATE CALIBRATION AND DERIVATIVE ANALYSIS IN THE SPECTROPHOTOMETRIC DETERMINATION OF SOME ASCORBIC ACID PHARMACEUTICAL MIXTURES

Bulletin of Pharmaceutical Sciences. Assiut ◽

10.21608/bfsa.2004.65453 ◽

2004 ◽

Vol 27 (2) ◽

pp. 269-280

Author(s):

Ibrahim Refaat

Keyword(s):

Ascorbic Acid ◽

Spectrophotometric Determination ◽

Multivariate Calibration ◽

Derivative Analysis

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Decomposition of peroxobenzoic acid in benzene catalyzed by transition metal 2,4-pentanedionates

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19840673 ◽

1984 ◽

Vol 49 (3) ◽

pp. 673-679 ◽

Cited By ~ 1

Author(s):

Pavel Lederer ◽

Eva Mácová ◽

Josef Vepřek-Šiška

Keyword(s):

Transition Metal ◽

Reaction Rate ◽

Reaction Products ◽

Acid Decomposition ◽

Analogous Experiment ◽

Catalytic Effects

The decomposition of peroxobenzoic acid in benzene was studied, and catalytic effects of Fe(III), Mn(III), Co(II), Co(III), and Cr(III) on the reaction rate and the composition of the reaction mixture were investigated. An analogous experiment carried out in perdeuterobenzene and determination of the distribution of deuterium in the reaction products provided evidence for the participation of the solvent in peroxobenzoic acid decomposition.

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