Correction - "Phase Equilibria in Hydrocarbon Systems. Volumetric

and pressure through proper instrumentation is also important. An adequate system for normal and emergency venting to a safe location should be provid...
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INDUSTRIAL AND ENGINEERING CHEMISTRY

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Continue purging until all air is removed. Close vent valve K and regulator by-pass valve J Close valves G and I . Open telltale valve H 2. Start ethylene oxide feed Open valve B, close valve C, and open valve D Open valves E and F after pressure on the cylinder has reached the desired point (not over 50 pounds per square inch gage) When proper liquid level has been built up in the vaporizer, open steam or hot water to coils After pro er pressure has been reached on vaporizer, open vaLe L to process 3, Shut off ethylene oxide feed Close valve L Shut off steam or hot water to coils Close valw E and F Close valves D and B. Open C This procedure will leave the container ready for shipment back to the manufacturer. The vapor phase in the insulated drum is principally the inert gas used to force out the ethylene oxide. If the vaporber is to remain down for a short period of time, the vapor phase should be blanketed with an inert gas. If it is to remain down for an indefinite time, the ethylene oxide should be removed and the vaporizer purged with an inert gas. USE IN CHEXICALREACTIONS.Because of the explosive characteristics of ethylene oxide vapor and the generally ex+ thermia nature of the reaction of the liquid with various materkIs, precautions are required when the compound is fed into a reaction mixture. The vapor phase of reactions under pressure should be diluted or blanketed with an inert gas. Proper agitation assures complete mixing of the ethylene oxide with the reactants and prevents formtion of “pockets” of liquid ethylene oxide. This avoids loss of control of the reaction and possible rupture of low pressure rewtors. Some means of cooling the reaction should be provided, such as internal coils or an external cooler using water or a refrigermt as the cooling medium. The control of temperature and pressure through proper instrumentation is also important. adequate system for normal and emergency venting to a d e location should be provided. In addition, safety valves and rupture diaphragms should be installed and should be of sufficient siae to relieve the pressure in the event of abnormal reactions other than explosions. Check valves should be installed in feed lines in an effort to prevent the reactants from entering an insulated drum, vaporizer, or any v d containing pure ethylene oxide. This precaution is necto avoid the poaeibility of undesirable reactions, which in some c w e ~might cause excessive pressure increases. LITERATURE CITED

(1) Aesoniated Factory Mutual Fire Insuranee Companies, IND. (2) I

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ENQ.CEFDM., 32,882 (1940). Burden. F. A.. and Burgoyne, J. R., Proc.Roy. SOC.London, 199, ,

328 (1949). (3) Carbide and Carbon Chemioals Division, Union Carbide and Carbon Corp., data. (4) G u D ~A.~ K., , J . SOC.Chem. Id.. 68, 179 (1949); FIAT, Final . ‘ Rs&1311. (5) Kaye, S.,and Phillips, C. R.,Am. J . Hug., 50, 270-305 (1949). (6) Kharaach, M. S.,Bur. Standards J . Research, 2,359 (1929). (7) Ifistiakomky, G.B., and Rice, W. W., J . Chem. Phys., 8, 620 (1940). (8) Lindgren, D.L., and Shepard, H. H., J . Econ. Enlomol., 25, 248 (1932). (9) Maass, O.,and Boomer, E. H., J . Am. Chem. Soc., 44, 1709 (1923). (10) McLaughlin, R.S.,Am. J . Ophllmlmol., 29,1355 (1946). (11) MeC, E.,b d l . Sachversttlnd. Ztg., 44,155 (1938); J . Ind. Hug. Toxicol., 20, 197 (1938) (abstract). (12) Meta, E.,Samml. Vergijtungsfullen, 10, 37 (1939); J . I d . Hug. Tozicol., 23,33 (1941) (abstract). (13) Perkin, W. H., J . Chem. Soc.,63, 488 (1938). (14) Peytral, E.,Bull. noc. chim., 39,206-14 (1926). (15) Sexton, R. J., unpublished data. (16) Sexton, R. J., and Henson, E. V., J. Ind. Hug. Tozicol.,31, 297 (1949). (17) Smyth, H.F.,Jr., private communication. .

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(18) Von Oettingen, W., Occupation and Health, Suppl., October 1939. (19) Waite, C. P., Patty, F. A., and Yant, W. P., U.8.Pub. Healfh Repts., 45, 1832 (1930). (20) Wan, 9.-W., and Dodge, B. F., IND.ENO.CHEM.,32,96 (1940). RECEIVED January 30, 1960.

Phase Eauilibria in Hvdrocarbon Systems-Correction J

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In the article entitled “Phase Equilibria in Hydrocarbon Systems. Volumetric and Phase Behavior of t t , MethanePropane System” [Reamer, Sage, and Lacey, IND.ENG.CHEM., 42, 534-9 (1950)], errors occurred in some of the reported values of molal volume of bubble-point liquid. These errors relate to states rich in propane and resulted from an improper method of calculation. A few modifications in molal volumes of the condensed liquid at states near bubble point also were involved. Tables I and I1 present revised values for the states concerned.

TABLE I. CORRECTION MOLALVOLUMES OF MIXTURES OF METHANE AND PROPANE IN LIQUID PJUSE~ 0.1

Pressure, Lb./Sq. Inch Absolute 0.2 0.3 0.4 0.5 0.6 Mole Fraction Methane At 40” F. ... ,, 1.295

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Bubble point 1.485

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At 100’ F.

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At 160’ F. Bubble point 1.834 1.963 .. . , . ., ... .. a Values not listed are correat aa preaented in Table I of basic reference. b Molal volumes expressed in cubic feet per pound mole.

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TABLE 11. CORRECTED MOLALVOLUMESAT BUBBLE POINTFOR METHANE-PROPANE SYSTEM“ Preasure Lb./Sq. h c h Abs. 40° F. 70° F. looo F. 130° F. 180’ F. 190° F. 79, 1.347c ... ,.. ... i25b , 1 .iiz .., ... 100 1.343 ... 160 1.336 1:iio 200 1.329 1.405 1:494 ... 260 1.322 1.400 1.491 300 1.315 1,395 1.489 1:&4 1 ,604 360 1.308 1.390 1.487 400 1.302 1.385 1.488 1.484 1 606 11776 450 1.297 i.asi 600 1.291 1.376 1.484 1 ,609 1.789 550 1.286 ... 1.484 1.611 1.803 1.615 1.484 600 1.281 ... 1.817 1.484 650 1.277 1 ,620 1.834 ... 1.484 1.851 700 1.273 ... ... ... ..* 726 750 1:ZiO . . . 1:486 ... 800 1.269 . . . 1.488 . * * 850 1.289 . . . 1.490 . . . 900 1.270 ... . . . 1.495 950 1.271 ... . . . 1.502 . . . 1434d . 1.892 .,. 1353d ... 2:ios ... 12184 ... ... ... 2:2i)3 . 767d ,.. 2:io State%not inoluded in thw table are correct as presented in Table I1 of hasic referenco. b Vapor pressure of propane. c Molal volumes expressed in oubio feet per pound mole. d Critical states.

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H. H. REAMER, B. H. SAGE,AND W. N. LACEY