Carbon-chloroform extractables

Brazos River water contains a relatively high concentration of total organic carbon (TOC) in the summer. Some of this carbon is removed in the floe as indicated by both the CCE (Carbon Chloroform Extract) and TOC. 

In the early 1960s, over 19,000 municipal water systems had been identified. These systems drew surface waters for treatment into drinking water. At this time, however, federal water pollution control efforts revealed that chemical and industrial wastes had polluted many surface waterways. Thus, the 1962 standards provided the addition of more recommended maximum limiting concentrations for various substances such alkyl benzene sulfonate, barium, cadmium, carbon-chloroform extract, cyanide, nitrate, and silver. 

The 43 g. of basic mixture remaining after removal of the buphanamine was dissolved in 500 ml. of chloroform and shaken with 500 ml. of N hydrochloric acid. The chloroform layer was washed twice with water, and the aqueous solution was washed with chloroform. The combined aqueous solutions were neutralized carefully with concentrated sodium hydroxide (ice cooling) and made alkaline with excess potassium carbonate. Chloroform extraction of the basic solution gave 13.0 g. of free bases which formed water-soluble hydrochlorides. 

As natural causes—aquatic plant and animal life—contribute organic substances, it follows that all waters can contain some extractables. In clean waters the carbon-chloroform extractables will often be less than 50, or even 25, parts per billion. In contrast, waters polluted with industrial waste may contain extractables in the hundreds or even thousands of parts per billion. The carbon-adsorption technique can be used to monitor the quality of drinking water supplies thus, water with less than 50 parts per billion of extractables can be presumed to be clean. The U.S. Public Health Service 1961 Drinking Water Standards actually call for a recommended limit of 200 ppb of carbon-chloroform extractables. 71... 

The large difference between the optimum dose of CI2 determined in this study and that reported by Robeck et al. 21) may result from the amount of CI2 consumed in oxidizing formulating solvents, plus the chlorine demand of the river water which was characterized by a chemical oxygen demand of 5-35 mg/liter and a carbon-chloroform extract of 185-1320 /xg/liter. 

Neutralise the cold contents of the flask with 500-600 ml. of 40 per cent, aqueous sodium hydroxide solution, equip the flask for steam distillation and steam distil until about 1 litre of distillate is collected. The steam distillate separates into two layers. Add solid sodium hydroxide (< 100 g.) to complete the separation of the two layers as far as possible. Remove the upper (organic) layer and extract the aqueous layer with three 50 ml. portions of chloroform. Dry the combined organic layer and chloroform extracts with anhydrous potassium carbonate and distil the mixture through a short fractionating column (e.g., an 8 Dufton column) after a fore run of chloroform, followed by pyridine, collect the crude 4-ethylpyridine at 150-166° (49 g.). Redistil through a Fenske-... 

A iridine traces in aqueous solution can be determined by reaction with 4-(p-nitroben25l)pyridine [1083-48-3] and potassium carbonate [584-08-7]. Quantitative determination is carried out by photometric measurement of the absorption of the blue dye formed (367,368). Alkylating reagents interfere in the determination. A iridine traces in the air can be detected discontinuously by absorption in Folin s reagent (l,2-naphthoquinone-4-sulfonate) [2066-93-5] (369,370) with subsequent chloroform extraction and hplc analysis of the red dye formed (371,372). The detection limit is ca 0.1 ppm. Nitrogen-specific thermal ionisation detectors can be used for continuous monitoring of the ambient air. 

Cyclohexanedione (5) 2,5-Dicarbethoxy-l,4-cyclohexanedione (10 g) is suspended in a solution of 34 g of 85 % phosphoric acid, 250 ml of water, and 5 ml of ethanol in a 500-ml round-bottom flask. The mixture is refluxed for 5 days (or until all the solid material has dissolved), cooled, and extracted six times with 100-ml portions of chloroform (or better, continuously extracted with chloroform). The combined chloroform extracts are dried (sodium sulfate) and the solvent is removed (rotary evaporator). The residue on distillation affords 1,4-cyclohexanedione, bp 130-133720 mm. The product solidifies and may be recrystallized from carbon tetrachloride, mp 11-19°. 

The filtrate was extracted twice with 100 ml of carbon tetrachloride. The carbon tetrachloride phase was discarded. The aqueous phase was adjusted to pH 11 by addition of 6 N aqueous sodium hydroxide and extracted four times with 300 ml portions of chloroform. The combined chloroform extract was washed three times with 100 ml of saturated aqueous sodium chloride solution and the sodium chloride phase was discarded. The chloroform extract was dried over anhydrous magnesium sulfate, filtered and the filtrate evaporated to dryness under vacuum on a 50° to 60°C water bath. The residue was a clear, colorless glass weighing 45 g analyzing about 95% 7(S)-chloro-7-deoxylincomycin. 

The ethyl p-chlorophenoxyisobutyrate may be obtained by heating a mixture of 206 parts of dry p-chlorophenoxyisobutyric acid, 1,000 parts of ethanol and 40 parts of concentrated sulfuric acid under reflux during 5 hours. The aicohol is then distilled off and the residue is diluted with water and extracted with chioroform. The chloroform extract is washed with sodium hydrogen carbonate solution, dried over sodium sulfate and the chloroform removed by distillation. The residue is distilled under reduced pressure and there is obtained ethyl p-chlorophenoxyisobutyrate, BP 148° to 150°C/20 mm. 

When addition is complete the mixture is heated under reflux during 5 hours and then the acetone is removed by distillation. The residue is dissolved in water, acidified with hydrochloric acid and the mixture extracted with chloroform. The chloroform extract is stirred with sodium hydrogen carbonate solution and the aqueous layer is separated. The alkaline extract is acidified with hydrochloric acid and filtered. The solid product is drained free from oil on a filter pump, then washed with petroleum ether (BP 40° to 60°C), and dried at 50°C. The solid residue, MP 114° to 116°C, may be crystallized from methanol (with the addition of charcoal) to give p-chlorophenoxyisobutyric acid, MP 118° to 119°C. 

The methanol is evaporated with agitation. The residue is dissolved in 1.5 liters water and is repeatedly extracted with chloroform. The combined chloroform extracts are evaporated to dryness, and the residue is recrystalllzed from carbon tetrachloride. 80 g of 2-amlno-5-methoxyethoxypyrimidine of MP 80°C to 81 °C are obtained. 

A PET oligomer isolation method has utilised chloroform extraction in a Parr bomb lined with a Teflon-TFE fluoro-carbon resin [40]. The analytics of fluoropolymer processing aids (combustion analysis, XRF, EUR, 19F NMR, OM) have recently been described [29]. Combustion analysis (Parr Oxygen Bomb Calorimeter) can be used for quantitative analysis... 

We have used the Kupchan scheme successfully in the separation of the multifunctional diterpenoid kalihinols from various Acanthella species (cf. Sect. 4.2.2). These compounds were distributed between the carbon tetrachloride and chloroform layers [19, 25], No isocyanosesquiterpenes were present in the hexane layer. By contrast, separate experiments with the Australian A. klethra revealed that sesquiterpenoid isonitriles were found exclusively in the hexane extract. No kalihinols were present in the carbon tetrachloride or chloroform extracts [26],... 

Laughlin et al. [122] analysed chloroform extracts of tributyltin dissolved in seawater using nuclear magnetic resonance spectroscopy. It was shown that an equilibrium mixture occurs which contains tributyltin chloride, tributyl tin hydroxide, the aquo complex, and a tributyltin carbonate species. Fluorometry has been used to determine triphenyltin compounds in seawater [123]. Triph-enyltin compounds in water at concentrations of 0.004-2 pmg/1 are readily extracted into toluene and can be determined by spectrofluorometric measurements of the triphenyltin-3-hydroxyflavone complex. 

The data recently published by Ouchi and Imuta (15) on a chloroform extract of Yubari coal also indicates similarities to petroleum. Branching is greater at the low carbon numbers and drops off at higher carbon numbers as in crudes (II) and Fischer-Tropsch product (17). The other similarity to crude oil is noted in the odd-even alternation of normal alkanes from Cm to C25 with the odd carbon number alkanes predominating. 

Aqueous samples extracted with chloroform chloroform extract further extracted with 1 M HjSO, the acid extract buffered with 0.4 M sodium tribasic phosphate and then pH adjusted between 6 and 7 using NaOH the neutralized extract then treated with chloroform organic layer separated and concentrated benzidine analyzed by HPLC using an electrochemical detector (i.e., glassy carbon electrode). 

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