July 1948
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I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
(8) Cameion, Ei. K., and Huiat, L. -4.,Zbid., 26,885 (1904). (9) Cameron, F. K.. and Seidell, A., Ibid., 26, 1454 (1904) : 27,1503 (1905). (IO) Causse, H., Compl. rend., 114,414 (1892). (11) Davis, W. A., J . SOC.Chem. Znd., 26, 727 (1907). (12) Elmore, K., andFarr, T., IND. ENG.CHEM.,3 2 , 5 8 0 (1940). (13) Haddon, C. L., and Blown, M . A . W., J . SOC.Chem. Znd., 43, 11 (1924). (14) Halla, F., 2. Krist., 80, 349 (1931); Z . angrw. Chem., 41, 659 (1931). (15) Hill, A. E., J . Am. Chem. Soc., 59, 2242 (1937). (16) Hill, W. L., and Hendrirks, S . B., IND.ENG.CHEM.,28, 440 (1936). (17) Hill, W. L., andJacob, K. D., J . Assoc. OficiaZAgr. Chemists, 17, 487 (1934). (18) Holt, L. E., La Mer, V. K., arid Chown, H. H . , .J. Biol. Chum., 64, 509, 567 (1925) (19) Jung, H., 2. anorg. Chem., 142, 73 (1925). (20) Kolh, J., Compt. rend., 78, 825 (1874). (21) Le Chatelier, H., "Recherches exp&-imeritales sur la Constitution des Mot tiers hydroliques," Paris, 1887.
1293
(22) Linck, G., and Jung, H., 2. anorg. Chem., 137, 407 (1924). (23) Lugg, J. W. H., T r a n s . F a r a d a y Soc., 27,297 (1931). (24) McCandless, J. M., and Burton, J. A,, IND.ENG.CHEM.,16, 1267 (1924). (25) Marshall, H. L., Hendrickb, S . B., and Hill, W. I,., Ibid., 32, 1631 (1940). (26) Marshall, H. L., and Hill, W. L., I b i d . , p. 1129. (27) Partridge, E. P., and White, A. H., J . Am. Chem. Sor., 51, 360 ( 1 929). (28) Posnjak, E., Am. J . Sci., 35 A, 247 (1938). (29) Ranisdell, L. S., and Partridge, E. P., Am. M i n e d , 14, 59 (1929). (30) Roller, P. S., J . Phys. Chem.,35, 1132 (1931). (31) Sanfourche,A., and Facet, B., Bull. soc. chim., 53, 1221 (1933). (32) Sanfourche, A,, and Krapivine, A , Zbid., p. 1573. (33) van't Hoff, J. H., 2. physik Chem., 45, 257 (1903). (34) Viard, Compt. rend., 114,414 (1892). (35) Weiser, H. B., Milligan, W.O., and Eckolm, W. E., J . Am. Chem. Soc., 58, 1261 (1936).
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RE,CEIVED March 4, 1947
SYSTEM LBUTENE-n-BUTANE Compositions of Coexisting Phases B. H. SAGE AND W. N. LACEY California Institute of Technology, Pasadena, Calif. ,.I
[ h e compositions of coexisting gas and liquid phases in the 1-butenen-butane system were experimentally determined for seventeen equilibrium states at four temperatures ranging from 100' to 280' F. The results, which were not of great accuracy, were correlated graphically by plotting the isobaric difference in the mole fractions of I-butene i n the two phases as isothevmal functions of the .mole fraction of 1-butene i n the liquid phase. Throughout the interval of temperature experimentally investigated the observed difference between the composition of coexisting phases i s markedly less than that predicted by Haoult's law.
E C E N T developments in petroleum processing have emphasized the need for data on the phase behavior of systems containing both paraffin and olefin hydrocarbons. I n the present investigation equilibrium phase compositions were determined for the 1-butene-n-butane system at loo", 160°, 220°, and 280" F. The volumetric and phase behavior of 1-butene was investigated earlier a t pressures up t o 10,000 pounds per square inch for temperatures between 100" and 340" F. (4). The properties of n-butane at temperatures and pressures of interest in the present study were reported by several investigators ( I , $ , 3 ) . MATERIALS
The 1-butene used in this study was prepared by dehydration of n-butyl alcohol using activated alumina as a catalyst. Details of the process of preparation and purification were described in a n earlier publication (a). A sample of the material used in the investigation varied less than 0.3 pound per square inch in its vapor pressure from bubble point t o dew point at 100'F. The n-butane was obtained from the Phillips Petroleum Company together with a n analysis which indicated the presence of less than 0.003 mole fraction isobutane and negligible amounts of other impurities. This material was fractionated in a 4-foot vacuum jacketed column packed with small helical glass rings. The column was operated at atmospheric pressure with a reflux
ratio of about 50 t o 1. The initial and final portions of the material fractionated were discarded, and the intermediate fraction amounting t o approximately 0.8 of the total overhead product was condensed at liquid-air temperatures at a pressure of about 4 X 10-6 inch (10-4 mm.) of mercury in order t o remove noncondensable gases. A sample of the material prepared in this manner had a vapor pressure at 100' F. which agreed t o within 0.1 pound per square inch with the value of 51.5 pounds per square inch absolute for the vapor pressure of pure n-butane. APPARATUS AND PROCEDURE
Th.: equilibrium chamber used for the study of this system had sample ports at the midpoint and at the top of the cell. After the amount of material in the cell was adjusted so that the lower sample port was in contact with the liquid phase and the upper port with the gas phase, the system was brought t o equilibrium at the desired state with the aid of mechanical agitation which was accomplished by the rotation of a n internal stirrer. Isobaric conditions were maintained in the equilibrium cell during withdrawal of the samples by injecting mercury at, a suitable rate. Duplicate gas and liquid phase samples were withdrawn at each experimentally observed state. The samples were collected in evacuated 500-ml. bulbs provided with glass stopcocks and standard taper ground-glass joints. The bulbs were filled t o slightly more than atmospheric pressure and the samples were then transferred t o the analytical apparatus. The amount of 1-butene in a sample was determined by volumetric, catalytic hydrogenation methods (6). From the measured diminution in volume as a result of the hydrogenation of the 1-butene and from the original volume of the sample and the total volume of the sample and hydrogen, the mole fraction of unsaturated hydrocarbon was computed, taking irito account the deviations of the hydrocarbons from perfect gas and ideal solution behavior. The analytical measurements permitted the calculation of a t least two, and generally three values of the mole fraction of n-butene from each set of data. The average of these calculations was taken as the most probable value for the particular state. t
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INDUSTRIAL A N D ENGINEERING CHEMISTRY
Vol. 40, No. 7 EXl’h,H I R 1hN r A L RESULTS
The mean value of the mole fiac tion of 1-butene in each of the Samples analyzed, ab computed from the aiialvtical rcsults, is recoided In Table I. Isothermal curve5 0 03 sho\%ingthe isobaric difference in 4 mole fraction of 1-butene in the gas I and liquid phases as a function of *‘ a 0 2 the mole fraction of 1-butene in th(, liquid phase are presented in Figuie 1 . The ube of the differences in 0.01 mole fraction provides a more wmsitive indication of consistencv in the data, as it emphasizes vaii0 2 04 06 ations in a smaller quantity than would be the case if the mole fracMole Fraction 1-Butene tion in the gas phase had been Figure 1. Effect of Temperature on the Relation between the Mole Fraction of plotted directly. 1-Butene in the Liquid Phase and the Isobaric Difference in the RIok Fractions If both components of the system of 1-Butene i n the Gas and Liquid Phase are assumed to behave in accordance ITith Raoult’s law, it may be shown that the difference in mole fraction of 1-butene in the gas and TABLI’: I. F;XPEHIMESTALLY OBSERVED COVPO~ITIONS013’ liquid phases is related to the composition of the liquid phase as COEXISTING PHASES foll OWR : (104
‘re mu., O F ,
100
Pressure, Lb./Sq. In. Abs. 5 2 .3 5 4 , .i 56.8 59.6 61.7
160
122.6 126.9
130.4 136.8 141.2
220
244.9 252.7 270,8
278.4 280
444.7 4 5 4 . ti
484, .5
Mole Fraction 1-Butene Gas Liquid 0.1237 0,1060 0.1205 0.1050 0,3088 0.2719 0.3105 .... 0.4728 0,4382 0.4810 0,4436 0,7190 0.6881 0.7212 0.6889 0.9329 0.9313 .... 0.9310 0.1165 0.1042 0.1140 0 . I015 0,2980 0.2708 0.2967 0.2697 0,4658 0.4365 0 ,4669 0.4384 0.7232 0.694%
I______
’
0.7190
0,9339 0,9351 0.1108
:
0 2876 0.2879 0.7174 0.7082 0.9311 0,9287 0,1377 0,1388 0.2787 0,2786 0,7014 0,7009
As shown in Figure I, the differences between duplicate experimental values are larger than would be desirable. The greater part of the inconsistencies probably resulted from uncertainties in the analytical techniques. However, the dispersion of the experimental values is less than the deviation‘from Raoult’s law behavior as shown for 100 F. by the dashed curve in the figure. Corresponding deviationi: at higher temperatures are markedly greater.
....
0,9299 0.9269 0,0982 0.0971 0.2649 0.2649 0.703l 0.6971 0.9221 0,9218 0.1316 0.1310 0,2733 0.2676 0.6918 0,6917
h platinum resistance therniometer \Tab used to measuie the temperature of the oil bath in xhich the equilibrium cell was immersed. It was calibrated by comparison with a similar standard instrument and it is estimated that the uncertainty in the temperatures reported is less than i.O.05 O F. The pressure in the equilibrium cell TYas measured by use of a piston-and-cylinder pressure balance, similar in principle to one described earlier (6). The uncertainty in the measurement of pressure was about *0.3y0. The estimated uncertainty in the composition of a phase is, for the most part, of the order of *0.002 mole fraction, although for several of the states uncertainties of as much as *0.005 mole fraction exist. Although this uncertainty is not unusually large for such equipment, the accuracy obtained leaves much t o be desired in determining the differences in the compositions of the coexisting phases. For this reason, the experimental results should be considered to be of preliminary nature and subject t o later refinement, when more accurate analytical methods are employed.
SIvIOOTH1:D AND I N T E R P O L %TED RESULTS C O S C E R X I N G COMPOSITIOSs O F COEXISTINL P H A S E S
TABLE 11.
.~At 1000 1’.
Preq-
sure, It3.Jsq in. ahg.
At 1800 ._-_Pres17.
sure, lb./sq. in. ahs.
A t 220’ F.
L-___
Yi YI 0.000 120.6 0.000 122.8 0.110 I2.6 0.115 0 , l 0.120 03.7 0.223 123.0 0 . 2 0.232 0.217 53.0 0.330 128.4 0.322 0 . 3 0.337 56.2 0.431 129.8 0.423 0.2 0 . 4 3 9 n . J 0.637 5 7 . 4 0 . 5 3 1 1 3 2 . 1 0 . 5 2 3 p8.5 0.628 134.4 0.620 0 . 6 0.634 09.8 0.723 136.6 0.716 0.7 0.728 60.6 0.816 138.8 0.811 0 . 8 0.821 140.8 0.905 61.6 0.908 0 . 9 0.911 1 . 0 1.000 6 2 . 5 1.000 142.9 1.000 a X I = mole fraction I-hurene in liquid phase. h 1’1 = mole frartiori 1-butene i n gas phase. .Ylu
Y,h
0.0 0 . 0 0 0
31 . 5
Presmre, lb./sp. in. abs. 241.2 245.3 249.4 253.6 257.7 261.9 280.0 270.1 274.3 278.4 282.6
At 280° E’.
YI 0.000 0.107 d.211 0.314 0.415 0.514 0.612
0.709 0.806 0.903 1.000
Pressure, Ib./sq. in. ahs. 436 443 450 457 464 471. 478 485 492 $99
m
Large scale isothermal plots relating the pressure of the system in the two-phase region to the composition of the liquid phase m r e prepared and curves were dravx with the simplest Corm capable of representing the experimental results within the estimated unccrtainty of the pressure and composition measurements.. Interpolated values read from these plots combined with values t,aken from the curves shown in Figurc 1 furnished the resulk recorded in Table 11. KO indication of the occurrence of constant boiling mixt,ures was observed in t,his system in the rangc of temperat,ure investiyakd. Table I11 compares values froni Table TI with those predicted by Raoult’s law under such conditions that, the mole fractions of the two component,^ in the liquid phase are equal. The observed
July 1948
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
TABLE 111. COMPARISON O F OBSERVED BEHAVIORAND PREDICTED FROM RAOULT'S LAW
THAT
(RIole fraction 1-butene in liquid phase = 0.5) Y1 - Xi" reinp , OI' Predicted Observed 100 0,048 0 039 160 0 042 0 031 220 0.040 0.023 280 0.037 0 015 a Y I 7 mole fraction 1-butene in gas phase; XI = mole fraction 1-butene in liquid phase.
1301
Corporation; for the interest and valuable advice of Manson Benedict; and for the assistance of D. F. Botkin ifi the experimental work. NOiMENCL4TCJRh
P,"= vapor pressure of I-butene, lb. per
sq. in. absolute
Pg = vapor pressure of n-butane, lb. per sq. in. absolute X I = mole fraction 1-butene in the liauid - -Dhase Y I = mole fraction 1-butene in the gas phase LITERATURE CITED
difference in the compositions of the gas and liquid phases is consistently less than the calculated one; this indicates that a poorer separation of the components is obtained during the course of a fractional distillation than would be predicted by Raoult's law. 4CKNOWLEI)GMENT
Acknowlcdgment is made for financial assistance and encouragement in this study from the Polymerization Process
(1) Beattie, Simard, and Su, J . Am. Chem. Soe., 6 1 , 2 4 (1939). (2) Kay, I N D *ENQ* CHEM.l 3%358 (1g40).
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(5) Ritohie, Cole, and McMillan, IND. ENG.CHEM.,ANAL.ED., 8, 105 (1936). (6) Sage and Lacey, Trans. Am. Inst. [Mining Met. Engrs., 136, 136 (1940). RECEIVED March 2% 1947.
WOOD PRESERVATIVES Effect on Seam Compounds and Value a s Paint Primers WILLIAM SPACKMAN, JR.', AND OSWALD TIPP02 In*dustrial Test Laboratory, Philadelphia Naval Shipyard, Philadelphia, Pa
A
study of 832 test panels simulating ship planking showed that wood preservatives, of the copper naphthenate, chlorinated phenol, and phenyl mercury oleate types, produce no deleterious effects on the calking compounds used to seal the seams of wooden vessels. These preservatives are also shown to have no effect on the occurrence of paint failure if an adequate drying period is provided and if the normal priming coat of paint is applied. The tendency of the copper naphthenate to bleed through the paint film is materially reduced by the use of a good paint primer. The preservatives are of little value as paint primers, both from a theoretical and an experimental standpoint. They have few of the characteristics of a good primer and show up very poorly when used in place of the regular priming coat of paint. The study was made as a part of the United States Navy's program of research in wood preservation at the Industrial Test Laboratory, Philadelphia Naval Shipyard, Philadelphia, Pa.
M
I N E sweepers, net tenders, aircraft retrieving boats, aircraft refueling boats, PT boats, motor launches, and motor nhale boats were required in large numbers for the Navy's role in the recent war. As these are mainly wooden craft, numerous problems arose early in the war in connection with the storage, fabrication, and preservation of wood. I n a n attempt to find the solutions to some of these problems the Bureftu of Ships established a wood section a t the Industrial Test Laboratory of the Philadelphia hTaval Shipyard. At this laboratory investigations were conducted on the problems associated with the bending of wood @4), the prevention of checking and warping, the protection against marine borer damage, and the prevention of I Present address, D e p a r t m e n t of Biology, H a r v a r d University, Cambridge, Mass. 2 Present address, D e p a r t m e n t of Botany, University of Illinois, Urbana, Ill.
wood decay (26). I n the case of the latter two, considerable work was done on three types of preservatives which were developed by the oil refining and chemical industries during the decade preceding the war. These preservatives, of the copper naphtbenate, chlorinated phenol, and phenyl mercury oleate types, were adopted by the Navy in preference t o the older creosote and zinc chloride types whose limitations for water craft use have long been recognized. I n addition to investigations of the effectiveness of these relatively new preservatives as fungicides and shipworm inhibitors, it was necessary to determine the stage of construction a t which these preservatives could best be applied, as well as the best method of applying them. It was important t o establish the extent of the fire hazard involved in their use, and the nature of their effect on the health of the workmen who would be treating the wood. Further, it was necessary to discover the effect of these toxic agents on other materials that would be placed in close contact with the preservative-treated wood, such as the calking compound used to fill the seams between the ship's planking and the paint that is applied after the completion of the construction of the vessel. The present paper deals with the relation of the preservatives to the seam compounds and to the paint. After the application of planks t o the frames (ribs) of a ship, there remain between the planks imperfect seams through which water may seep. I n order t o block these seams, a n appropriate amount of cotton is driven into the space by means of a calking iron and a wooden mallet. The vessel is usually given a priming coat of paint after which the seam compound (a puttylike material) is applied with a putty knife, so that the seams are filled almost flush with the surface of the planking. The top coats of paint are then applied. If a preservative treatment is interjected into this schedule its timing will depend on whether the toxicant is applied by brush, by pressure, or by the hot and cold bath method. If either of the two latter methods is employed, the planks will have been treated by the time they are put in place on the frames. If the preservative is t o be applied by brushing or by
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