Carbon disulfide, distillation

White and red phosphorus, candle with a long wick, carbon disulfide, distilled water, filter paper. 

Quantitatively, sulfur in a free or combined state is generally determined by oxidizing it to a soluble sulfate, by fusion with an alkaH carbonate if necessary, and precipitating it as insoluble barium sulfate. Oxidation can be effected with such agents as concentrated or fuming nitric acid, bromine, sodium peroxide, potassium nitrate, or potassium chlorate. Free sulfur is normally determined by solution in carbon disulfide, the latter being distilled from the extract. This method is not useful if the sample contains polymeric sulfur. 

Manufacture. Trichloromethanesulfenyl chloride is made commercially by chlorination of carbon disulfide with the careful exclusion of iron or other metals, which cataly2e the chlorinolysis of the C—S bond to produce carbon tetrachloride. Various catalysts, notably iodine and activated carbon, are effective. The product is purified by fractional distillation to a minimum purity of 95%. Continuous processes have been described wherein carbon disulfide chlorination takes place on a granular charcoal column (59,60). A series of patents describes means for yield improvement by chlorination in the presence of dihinctional carbonyl compounds, phosphonates, phosphonites, phosphites, phosphates, or lead acetate (61). 

Other components in the feed gas may react with and degrade the amine solution. Many of these latter reactions can be reversed by appHcation of heat, as in a reclaimer. Some reaction products cannot be reclaimed, however. Thus to keep the concentration of these materials at an acceptable level, the solution must be purged and fresh amine added periodically. The principal sources of degradation products are the reactions with carbon dioxide, carbonyl sulfide, and carbon disulfide. In refineries, sour gas streams from vacuum distillation or from fluidized catalytic cracking (FCC) units can contain oxygen or sulfur dioxide which form heat-stable salts with the amine solution (see Fluidization Petroleum). 

Modem plants generally produce carbon disulfide of about 99.99% purity. High product quaUty is ensured by closely controlled continuous fractional distillation. Reagent and U.S. Federal specifications, and typical commercial-grade quaUty are Hsted in Table 5. 

Carbon Disulfide Chlorination. The chlorination of carbon disulfide [75-15-0] is a very old method of producing carbon tetrachloride that is still practiced commercially in the United States. In this process CS2 reacts continuously with chlorine in an annular reactor at 105—130°C. Product CCl is separated by distillation to a CS2 content of 0—5 ppm. By-product S2CI2 is reduced in a reactor at 450°C with hydrogen without a catalyst to give sulfur of 99.985% purity (32). Other processes use ferric chloride as a catalyst (33,34). 

Ethyleneamines are used in certain petroleum refining operations as well. Eor example, an EDA solution of sodium 2-aminoethoxide is used to extract thiols from straight-mn petroleum distillates (314) a combination of substituted phenol and AEP are used as an antioxidant to control fouling during processing of a hydrocarbon (315) AEP is used to separate alkenes from thermally cracked petroleum products (316) and TEPA is used to separate carbon disulfide from a pyrolysis fraction from ethylene production (317). EDA and DETA are used in the preparation and reprocessing of certain... 

A number ot aryl trifluoromethyl ethers are synthesized by fluormation of aryl chlorothioformates with molybdenum hexafluoride. The reagents are progressively heated from -25 to 130 C, and the products are distilled off. Molybdenum disulfide and carbon disulfide are the by-products [12] (equation 16)... 

Schwefel-kobalt, m. cobalt sulfide, -kohle, /. sulfurous coal, high-sulfur coal, -kohlen-saure, /. sulfocarbonic acid (trithiocarbonic add, HaCSa). -kohlenstoff, m. carbon disulfide. -kolben, m. retort for distilling sulfur, -kora, -kbrachen, n. sulfur granule, -kuchen,... 

A mixture of 13,3 grams of anhydrous aluminum chloride and 100 ml of carbon disulfide is added to 19,4 grams of 2-propionyloxybenzoic acid (prepared from the reaction of pro-pionyl chloride and 2-hydroxybenzoic acid). After an initial evolution of hydrogen chloride, the solvent is removed by distillation and the mixture is heated at 150° to 160°C for 4 hours. The cooled reaction mixture is treated with ice and hydrochloric acid and the product, 2-hydroxy-3-carboxypropiophenone, is obtained from the oily residue by distillation in vacuo,... 

Figure 1 Apparatus for hot acid decomposition of aUsylenebis(dithiocarbamates) and distillation of carbon disulfide. 1 = Three-necked round-bottom flask 2 = air inlet tube 3 = dropping funnel 4 = Liebig reflux condenser 5 = gas washing tubes 6 = carbon disulfide absorption tube.

The carbon disulfide is decanted, and 200-300 ml. of water is added to the contents of the flask. Initially the mixture reacts slowly, but after some time the reaction becomes so vigorous that it is necessary to pour off the water (Notes 1 and 2). The addition of water, followed by its removal when the reaction becomes very vigorous, is repeated until decomposition is complete. The combined aqueous solutions are extracted several times with chloroform, and the combined extracts are dried over anhydrous sodium sulfate. Distillation of the solvent gives a dark brown liquid residue which is distilled under reduced pressure to give 310.3 g. (89%) of the thioamide as a yellow liquid, b.p. 133-135° (12 mm.) (Note 3). 

Typically, indium trichloride with excess As oxide and metal Zn powder were mixed in an aqueous HC1 solution, which was sealed in a stainless Teflon-lined autoclave. This was heated at 120°C for 18-24 hours, and then cooled to room temperature. The black product was washed with carbon disulfide, anhydrous methanol and distilled water and desiccated in vacuum. The residue was etched and dispersed in an -butanol dilute solution of HF and water, stirred and centrifugally separated. In the final product, spherical InAs nano-crystals were obtained. 

Residua are the dark-colored nearly solid or solid products of petroleum refining that are produced by atmospheric and vacuum distillation (Figure 11.1 Chapter 3). Asphalt is usually produced from a residuum and is a dark brown to black cementitious material obtained from petroleum processing that contains very high-molecular-weight molecular polar species called asphaltenes that are soluble in carbon disulfide, pyridine, aromatic hydrocarbons, and chlorinated hydrocarbons (Chapter 3) (Gruse and Stevens, 1960 Guthrie, 1967 Broome and Wadelin, 1973 Weissermel and Arpe, 1978 Hoffman, 1983 Austin, 1984 Chenier, 1992 Hoffman and McKetta, 1993). 

To a cooled (10°C) stirred solution of 30 gm (0.27 mole) of catechol in 150 ml of dry carbon disulfide and 42.4 gm (0.54 mole) of pyridine is added drop-wise 33.7 gm (0.28 mole) of thionyl chloride in 80 ml of dry carbon disulfide. After the addition the reaction mixture is allowed to stand at 10°C for hr, refluxed for hr, separated from the warm syrupy layer of pyridine hydrochloride, concentrated, and the residue distilled to afford 41 gm (97 %), b.p. 137°-138°C (105 mm). 

Arrange a water bath in such a way as to immerse the solution in it and distill off the carbon disulfide as completely as possible, since its presence interferes with the next step. Quickly replace the Liebig condenser with the air condenser and its train, as shown in Fig. 17, and renew the current of dry carbon dioxide until all air has been displaced from the apparatus. 

In a i-l. three-neck flask equipped with a mechanical stirrer, a reflux condenser, and a thermometer (with bulb immersed in the liquid), are placed ioo g. (0.75 mole) of anhydrous aluminum chloride and 300 g. of carbon disulfide (Note 1). The suspension is cooled to 15-25° and a solution of 60 g. (0.71 mole) of thiophene (p. 72) and 105 g. (0.75 mole) of benzoyl chloride in 225 g. of carbon disulfide is added through the condenser, with stirring, over a period of three and one-half hours (Note 2). The solution is allowed to warm up to room temperature, and stirring is continued for three more hours the reaction mixture is then allowed to stand overnight. The mixture is refluxed on the water bath for three and one-half hours, cooled, poured on ice, and extracted with ether. The ether extract is washed successively with sodium carbonate solution and water, and then dried over calcium chloride. The ether is removed by distillation on the water bath, and the residue is distilled under reduced pressure. The yield of product boiling at 200-209 V30-40 mm. is ir7-r20 g. (88-90 per cent of the theoretical amount). On crystallization from 1 I. of petroleum ether (b.p. 65-1x0°) there is obtained 110 112 g. of product melting at 52°. Another crystallization... 

The experiments may be run with a larger amount of carbon disulfide with satisfactory results. This, however, involves a longer time for distillation and is therefore undesirable. More concentrated solutions were not tried. 

Mesitoic acid has been obtained by hydrolysis of its amide which was prepared from mesitylene, carbamyl chloride, and aluminum chloride in carbon disulfide.1 It has been prepared by heating isodurene with dilute nitric acid,2,3 in small yields by the distillation of 2,4,6,-trimethylmandelic acid,4 by dry dis-... 

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