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Fig. 9.14 Six carbamates eluted in fraction III (portion of Carbofuran and Methiocarb in fraction II) 5.0ng of each compound gas chromatographic column, 5 OV-210. (Reprinted with permission from Thompson et al. 18 . Copyright (1977) Springer Verlag, New York.) Coburn et al. 315 reported a procedure for the extraction and analysis of N-methylcarbamates in natural water. Their procedure involved the extraction at pH3-4 by solvent partitioning with methylene chloride, salting out with sodium...

Introduction

1.1 Brief summary of methodologies 1.1.1 Titration procedures Anionic and cationic surface active agents, aliphatic amines, nitriles, amines, nucleic acid, nitriloacetic acid, mercaptans, disulphides, humic acid and fulvic acids, and also bromine, chlorine, iodine and organic nitrogen have been determined in a variety of water samples by titration procedures. As titration procedures are relatively insensitive compared to some other procedures, it is likely that they would be applied only to...

Ph3SnH Ph2SnH2 PhSnH3 SnPCV complex ecglccolorimetry

Gas-liquid chromatography was performed on a dual-column-dualdetector Varian Model 2400 instrument equipped, on one side, with a flame ionization detector and 0.7m x 2mm (i.d.) glass column containing 3 OV-17 on 60-80 mesh Gas Chrom Q. Column, injector and detector temperatures were 265, 275 and 300 C, respectively the carrier gas was nitrogen. Tetraphenyltin eluted within 8min under those conditions. The second side of the chromatograph was equipped with a tritium electron-capture detector and...

Xad7 Xad8

Alkanes, aromatic hydrocarbons, polyaromatic hydrocarbons, ethers, car boxy lie acids, phenols, alcohols, ketones, haloforms, ch I o robe men es, chloroaiiphatic hydrocarbons, polychlorobiphenyls, amines, amino acids, phosphorus- and chlorine-containing insecticides, chlorophenoxy and phenylacetic acid-type herbicides, Aminocarb and metabolites, kepone and miscellaneous organics Carboxylic acids, non-ironic surface active agents, aliphatic chloro compounds, polychlorobiphenyls,...

Organometallic compounds

Large amounts of arsenic enter the environment each year because of the use of arsenic compounds in agriculture and industry as pesticides and wood preservatives. The main amount is used as inorganic arsenic (arsenite, arsenate) and about 30 as organoarsenicals such as monomethylarsinate and dimethylarsinite. Arsenic is known to be relatively easily transformed between organic and inorganic forms in different oxidation states by biological and chemical action. Until recently, most of the...

Use Of Florasil As An Adsorbent In Chromatography

Sb between batch standard deviation. St total standard deviation. Sw within batch standard deviation. Sb between batch standard deviation. St total standard deviation. applied to a column (100mm x 4.2mm) of silica gel (Grace 950, 60- 200 mesh, dried at 30 C for 2h then deactivated with 5 of water). The column was then percolated (at 1mL min-1) in turn with hexane (20mL), benzene-hexane (3 2) (8mL), benzene (8mL) and ethyl acetate-benzene (1 1) (14mL). Each...

Gs13005

Paraoxon Parathion Parathion-ethyl Phorate (2-(ethylthio)ethyl)-O,O-dimethyl phosphorothioate phosphorothionate phosphorothioate 2,2-dichlorvinyldimethyl phosphate O,O-dimethyl-S-(2-(ethylthio)ethyl) phosphorodithioate phosphorothioate ethyl-S,S-diphenyl phosphorodithiolate thionate O- ethyl-S,S-diphenyl phosphordithioate phosphorothioate ethyl-S-phenylethyl phosphorothiolothionate ethyl-S-phenylethyl phosphorodithioate phosphorodithioate ethyl-4-(methylthio)-m-tolyl isopropyl...

D

Fig. 4.5 Differential pulse polarograms of tap water residues after nitration. A, blank B, tap water C, tap water + 11.2 Dg of LAS and D, tap water + 22.4Dg of LAS. Polarography was performed in Br buffer (pH 12) using an initial potential of -0.3V. (Reprinted with permission from Hart et al. 68 . Copyright (1979) Royal Society of Chemistry.) is carried out similarly. Use of an internal standard avoids interference from iron and from up to 1ppm of fluoride. Anionic detergents have been...

Surface active agents

4.1 Anionic detergents 4.1.1 Natural waters 4.1.1.1 Titration methods Bock and Reisinger 1 and Wickbold 2 have described a method for the determination of sodium dodecylbenzene sulphonate based on precipitation with p-toluidine and titration with sodium hydroxide. Wang et al. 3 have described a two-phase titration procedure for the determination of linear alkyl sulphonate and branched-chain alkylbenzene sulphonate in water. The method involves initial treatment of water sample with a known...

Oxygencontaining compounds

There are two sources of fatty acids in river water, man-made contamination and naturally occurring. Regarding the latter the determination of free and bound fatty acids present in aquatic systems is important first because fatty acids are sufficiently diverse in structure that they can be used to determine the source and cycling of organic carbon 1-5 and second because fatty acids iw vivo function primarily as structural compounds of membranes and energy storage products. In the reduced state...

Phosphoruscontaining compounds

Murray 1 has described a gas chromatographic method for the determination in water of triarylphosphate esters (1mol S-140, tricresyl phosphate, cresol phosphate). These substances are used commercially as lubricant oil and plastic additives, hydraulic fluids and plasticizers. The method involves extraction from the samples, hydrolysis and measurement of the individual phenols by gas chromatography as the trimethylsilyl derivatives. The lower detection limit was about 3ppm. In this procedure a...

Halogencontaining compounds

Gas Chromatography Charts

5.1 Saturated aliphatic halogen compounds Murray and Riley 1, 2 described gas chromatographic methods for the determination of trichloroethylene, tetrachloroethylene, chloroform and carbon tetrachloride in natural waters. These substances were separated and determined on a glass column (4m x 4mm) packed with 3 of SE-52 on Chromosorb W (AW DMCS) (80-100 mesh) and operated at 35 C, with argon (30mL min-1) as carrier gas. An electron-capture detector was used, with argon-methane (9 1) as quench...

Fenoprop

9.9.1 Natural waters 9.9.1.1 Gas chromatography Devine et al. 385 adjust the water sample (1L) to pH2 with hydrochloric acid and extract it with benzene (100, 50 and 50mL). The extract is dried over sodium sulphate, concentrated to 0.1mL and methylated by the addition of diazomethane in ethyl ether (1mL). After 10min, the volume is reduced to about 0.1mL, acetone is added and an aliquot is analysed by gas chromatography on one of three columns (1) 5 SE-30 on 60-80 mesh Chromosorb W at 175 C,...

Thinlayer chromatography

Thielemann 213 has described a thin-layer chromatographic method for the identification of phenolic impurities in diethyl ether or active carbon extracts of water. The separation and identification of o, m- and p-cresols, phenol, 2-naphthol, and 2,5,-, 3,4,- and 3,5-xylenols, after coupling with Fast Red Salt AL (CI Azoic Diazo Component 36), was carried out on Kieselgel G impregnated with potassium carbonate with the use of one of three solvents. Polyhydric phenols were not identifiable by...

Uv

Interest in developing a routine high-performance liquid chromatographic system that is capable of separating unknown and complex extracts with the best possible resolution of individual nonvolatile components. A system has been developed employing liquidsolid adsorption chromatography with gradient elution by the application of a series of solvents of rising polarity. A series of solvent reservoirs is connected via a programmable multiple port rotary valve to a solvent mixing chamber...

Oxygen demand parameters

Apart from the standard potassium chromate digestion procedure, several other procedures have been used for the determination of the chemical oxygen demand of natural waters including continuous flow injection analysis 1 , combustion-infrared spectroscopy 2 , titration with nitrate 3, 4 , spectrophotometry 5 and potentiometric titration 6 . In the direct potentiometric method for determining chemical oxygen demand, Dugin et al. 4 used a galvanic cell with no liquid junction. Reversibility of...

Cheeseman And Wilson Spectrophotometric Determination Of Phenol

Fig. 3.4 Gas liquid chromatography of alditol acetates of monosaccharides, formed by hydrolysis of DCHO in lake water (taken from the surface of Lake Nakanuma, Japan, on 26 May 1978). Peaks 1, rhamnose 2, fucose 3, ribose 4, arabinose 5, xylose 6, mannose 7, galactose 8, glucose 9, inositol internal standard. (Reprinted with permission from Ochiai 127 . Copyright (1980) Elsevier Science Publishers.) Steinle 129 has reviewed methods for the determination of carbohydrates in water samples. Eklund...

B

Fig. 5.14 Separation of a standard mixture of phenols on a Tenax GC column. Peak order (A) solvent impurity (B) phenol (C) o-cresol (D) 3,5-dimethylphenol (E) 4-chloro-3-methylphenol (F) 2,4,6-trichlorophenol (G) 2-napthol and (H) pentachlorophenol. Separations were obtained on a 18 in x 1 4 in (0.46m x 6mm) in SS Tenax GC column. Temperature held at 190 C for 1 min, then programmed at 10 C min-1 to 270 C and held at 270 C for 4min. (Reprinted with permission from Chriswell and Cheng 295 ....

Sulphurcontaining compounds

Duane and Stock 1 have discussed a titration method for determining thiols. Leek and Bagander 2 determined reduced sulphur compounds in natural waters by gas chromatography using a flame ionization detector. Substances determined include methyl mercaptan, dimethyl sulphide, hydrogen sulphide and carbon disulphide. Detection limits ranged from 0.2mg L-1 (carbon disulphide) to 0.6ng L-1 (methyl mercaptan). Heuatsch and Jutter 3 have discussed the gas chromatographic determination of dimethyl...

Nitrogencontaining compounds

6.1 Aliphatic amines 6.1.1 Natural waters 6.1.1.1 Spectrophotometric methods Florence and Farner 1 determined parts per billion (109) amines in waters, sea water and raffinates from uranium processing using a spectrophotometric procedure. Hermanson et al. 2 used an aluminium column (276cm x 4mm) packed with 80-100 mesh Chromosorb W supporting 8.9 of amine 220 at 95 C with nitrogen as carrier gas and flame ionization detection. A rectilinear response was obtained between peak area and amount of...

Retention Time Of Aldrine

Source Reprinted with permission from Suzuki et al. 10 . Copyright (1977) American Chemical Society. a Retention time of Aldrin was 4.99min. b No peak appeared. and microbially formed isomer of Dieldrin which was present in the field soil, could not be detected with a SCOT glass capillary column. This might be due to the thermal decomposition and or adsorption of Photodieldrin to the support of SCOT glass capillary column. The 'resolution index' with WCOT glass capillary columns was smaller...