INDUSTRIAL AND ENGINEERING CHEMISTRY
June 1950
carbon or organic phases. These are given for the methylcyclohexane and benzene systems aa Figures 10 and 11, respectively. Because of the low solubilities, this type of plot has not been attempted for the heptane system. Complete extraction of traces of aniline from a hydrocarbon stream by water scrubbing is concerned with the slopes of these curves aa they approach zero. For benzene, the slope is about 2, for methylcyclohexane at 25' C. it is about 5, and for heptane it is considerably above 6. These values indicate that aniline can be scrubbed completely from a hydrocarbon stream by counterflow treatment with water. The relative weight ratio of water to hydrocarbon for complete
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scrubbing is about unity for pure benzene and much leea than unity for the other hydrocarbons or their mixtures. Aniline is readily recoverable from water by fractionation (1). BIBLIOGRAPHY
(1) Griswold, et al., Im. ENG.CIIEM., 32,878 (1940). (2) Griswoid and Bowden, Ibid.,38, 609 (1046).
Seidell, A., "Solubilities of Organic Compounds," Vol. 11, 2nd ed., New York, D. Van Nostrand Co., 1941. (4) Varteresaitln and Fenake, IND. ENG.CHBM.,29,270 (1937). (8)
REOEIV8D September 18, 1948. Earlier papers of this series appeared in IND.ENQ.CRSM.,35, 247 (1943); 36,1119 (1944); 38,66, 170 (1946); and 41, 331 (1949).
ETHYLENE OXIDE Hasards and Methods of Handling L. G . HESS AND V. V. TILTON Carbide and Carbon Chemicals Diuleion, Union Chrbi.de and Carbon Corporation, South Charleston, W . Va. Ethylene oxide is stable to common detonating agents when in the liquid state. Recent experiments have indicated that ethylene oxide vapor, however, decomposes explosively when exposed to various ignition sources. The liquid phase muld not be detonated. Satisfactory methods of handling ethylene oxide were found when the explosive nature of its vapor was rewgnied. Results of a research study on its explosive properties are presented, together with suggested procedures for the handling and storage of this material. In order to present a complete discussion, chemical and physical properties, a few uses, and some data on toxieity of ethylene oxide are included.
E
THYLENE oxide, CzH40, is a cyclic ether, the structure of which may be represented as
I
CH/ The three-membered ring is capable of reaction with compounds having a labile hydrogen atom and reacts with such substances aa water, most alcohols, amines, ammonia, and organic and mineral acids. Thus, ethylene oxide is a useful starting material in the preparation of glycols, aldehydes, acids, esters, halides, amines, ethers, and many other derivatives. In a madified Grignard reaction it serves as a convenient reagent for the lengthening of a carbon chaii, two carbon atoms a t a time, Ethylene oxide k also valuable for removing the last traces of acidity in cases where aqueous alkalies may not be used. Ethylene oxide, as a fumigant, is highly toxic to certain insects and, in particular, to their eggs. Because it leaves no residual taste or odor, it is used to destroy certain molds and bacteria in food products. Because it is noncorrosive and has an agreeable odor, it may be used as an industrial fumigant. A nonflammable mixture of ethylene oxide and carbon dioxide, sold commercially as Carboxide fumigant, is convenient for this purpose (6).
TABLE I. PHYSICAL PROPERTIES OF ETHYLENE OXIDE Liquid Apparent speolfic gravity a t 20/20° C. A sp. gr./ At Average wei ht per gallon a t 20" C., Ib. Coeficient of expansion a t 200 C. At 6b0 C. Boiling oint a t 760 mm., C. mm' At(Ap. !40-780 mm., O Cd Boiling point a t 60 mm At 10 mm:: O C. Vapor pressyre a t 2Oo,C., mm. Hg Freeaing point C. Refractive i n d k nn a t 7O C. Viscosity a t 0" C., cp. Solubility in water a t loo C. Solubility of water in, a t loo C. Heat of vaporination a t 1 atm., B.t.u./Ib. Rash point, TAG glass open cup, C.
Reference
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1.3697 0.32 Complete Comalete 245
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