CARBON BISITLPHEDE, CARBONIC DISULPHIDE, SULPHOCA.RBONIC ACID, THIOCARBONIC ANHYDREDE. (Fn., Sulfure de carbone, Acide sulfocarbonique ; GER., Schtrefelkohknatoff.) CS2 = 76; relative weight, 38. Sp. gr. at 0° (32° F.), 1.0272; at 16° (60° F.), 1.272; sp. gr. of the vapour at 16' (60° F.) (theoretical), 2.6296; (observed), 2.64-17 ; boiling peint of the commercial article, 48° (about 118.4° F.), that of the pure substance 43° (109.4' F.).
Bisnlphide of carbon Ls a colourless, heavy, very volatile liquid, possessing an acrid, pungent taste, high refractory powers, and a very powerful fcetid, alliaceous odour, due to the presence of impurities in the unrefined product, but only giving off an ether-like smell when pure. It has been considered insoluble in water; but this is not strictly true, as, by prolonged contact, water will dissolve it at ordinary temperatures, in the proportion of about Tb-W, part of the weight of water. It may be mixed in almost all proportions with alcohol, ether, benzine, and the fixed and volatile oils; and it acts as a solvent of fats, oils, resins, indiarubber, sulphur, phosphorus, bromine, chlorine, iodine, camphor, S:e. It cannot be solidified in vacuo except it be mixed with ether, and for its congelation, under ordinary conditions, a very low temperature ia required; it may, however, easily be frozen by directing a very strong current of dry air upon the surface of the liquid. By the evaporation which ensues, so much heat is rendered latent that the mercury of a thermometer, placed in the vessel during the operation, will not have descended to 32°F. before a coating of the frozen substance will have been formed on the sides of the vessel. The temperature then falls rapidly to 0° F., while a white mammillated mass rises to the surface. When the whole mass haa solidified, the temperature rises again to 10' F., where it continues until melting supervenes. The bisulphide will remain solid for some time, and, while in this state, possesses a peculiar aromatic odour. It ia highly inflammable ; its vapour when mixed with air takes fire, accordiog to one authority, at about 119° (300° F.), exploding with great violence under some conditions; another authority asserts that, when mixed with hydrogen or carbonic oxide, it iguites below 216° (420° F.); it bums with a blne flame, giving rise to sulphurous and carbonic anhydrides. Further, it is deadly poisonoua, inhalation of the vapour producing giddiness, vomiting, congestion, and finally c,oma. The pure liquid, exposed to sunlight for a considerable time, undergoes partial and
gradual decomposition, turtling yellow, and depositing an insoluble brown substance. Bisulphide of carbon is composed of 15.8 per cent. of carbon and 84.2 per cent. of sulphur, and is produced by paasing the vapour of sulphur over charcoal kept at a red heat, or by diatilling an intimate mixture ot native metallic sulphides with charcoal or coke, the former being the only method employed commercially. Though not to be compared with sulphuric acid, for instance, as re2;ards its importanc,e among manufactures, it nevertheless takes a high place among chemical products, principally by reason of the fact that many substances formerly discarded as waste have, by its use, been made to render valuable returns.
Atatufacture.—Thc arrangement of the furnaces employed 10 bisulphide of carbon varies considerably. According to a very general plan, they conaist of four fireclay cylinders, each about .5 ft. 10 in. high, and 20 in. internal diameter, with a ring about 6 in. from the bottom, supporting an earthenware tray full of holes, which forms a grating. Each cylinder is furnished with three holes in the cover, the first for the introduction of the sulphur, the second for the escape of the gaseous bisulphide, the third and largest for the introduction of the charcoal. The opera tion being conducted without interniission, three charges of charcoal per twenty-forir hours are put into the cylinders, each of which is supplied at regular intervals of three minutes with charges of about 104 oz. of coarsely pulvelized charcoal, the four cylinders thus receiving, in the course of twenty-four hours, about 300 lb. of sulphur each, or a total of 1200 lb. The four cylinders are set perpendicularly in rnssonry, and heated by the flame of a single fire. A small porcelain tube about 24 in. diameter passes through the cover of each eylinder, and also penetrates the false bottom, while it rises about 10 in. above the cover. A second opening in the cover admita the end of a bent tube, about 3f in. diameter, hy which the gases make their escape to the coolers. Finally, the third opening, 6 in. diameter, is intended for the reception of the leg of a funnel each time charcoal has to be supplied to the cylinders.