Thermal Conductivity of Alcohols and Glycols - Industrial

Absolute measurements of the thermal conductivity of mixtures of alkene-glycols with water. M. J. Assael , E. Charitidou , S. Avgoustiniatos , W. A. W...
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INDUSTRIAL AND ENGINEERING CHEMISTRY

February, 1945

,

show that the wool breaks into coarser chunks free from the fines characteristic of the untreated material. The photomicrograph of wool treated with a surface resin such as polystyrene emulsion (Figure 4) shows the same small fragments of wbol along with a great deal of debris and what may be surface resin which has come loose. A dyed woolen blanket was treated with Resloom M-75, the melamine resin was cured and insolubilized by heating, but the treated blanket was not washed. Here is found a large amount of extraneous matter (Figure 5 ) which may be loose dyestuff or resin. The large fragments of wool indicate the toughening action of the melamine resin which has penetrated the fiber.

TABLE V. Resin Used

.... Methylolmelamine

EFFECT OF RESINON MOISTURE PICKUP

Cotton Sheeting % moisture regain at % 667' rel. resin humfdity" 5.88

..

Spun Rayon $7, mqisture regain at % 66% rel. resin humidity" 11.66

..

Wool Flannel yomoisture regain at %. 66% rel. resin humidity" . 10.32

1.0 2.4 5.0

. ...

5.87 1.2 11.00 9.6 5.41 3.0 10.95 4.69 6.1 10.42 i. 10.0 4.48 12.0 10.12 Methylol2.3 5.49 7.2 10.34 6.4 urea 5.6 5.14 ... .. Moisture regain is figured on the weight of the dry fiber.

..

..

10.52

... ... ...

10.62

...

COTTON. Cellulose has a characteristic subfibril structure (Figure 6) when mechanically disintegrated in water and examined under the electron microscope. Treatment of cotton fabrics with melamine type resins gives the fabrics (Figures 7 and 8) greater resilience and less tendency t o shrink on washing. Examination of melamine-treated fabrics which have been mechanically disintegrated shows certain differences under the electron microscope which are quite different from the effects noted on wool. After me'amine resin treatment the cotton fibers appear to break u p into subfibrils of the same thickness and length as the

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untreated, but these subfibrils seem to be caught or stuck together a t various points. This indicates that the resin acts as a n adhesive between the subfibrils and does not penetrate them as well as in the case of wool. The samples of cotton sheeting treated with a styrene dispersion (Figure 9) show again the surface effect of this resin with no effect on the way in which the subfibrils are formed. RAYON.The melamine and styrene resins have the same effect on rayon as they do on cotton. However, in the case of rayon the subfibrils are much shorter than those observed for cotton. This seems to confirm the reported observation that the degree of polymerization of cotton is appreciably reduced when i t is converted into rayon. A sample of tire cord rayon (Figure 10) with the fine debris in the background is characteristic of all the tire cords examined. The method of spinning this yarn probably makes i t extremely brittle so that i t breaks up under the mechanical disintegration. There is little difference in samples of spun rayon and filament rayon, both before and after treatment with styrene type resins (Figures 11 and 12). Care should be taken not t o draw rigid conclusions from these electron photomicrographs. The method of sampling and the silhouettes obtained clearly indicate that these pictures offer interesting vistas for speculation but not for proof. ACKNOWLEDGMENT

The author wishes to express appreciation for the great assistance of Dexter Reynolds and Elmer Rossin of the Monsanto Chemical Company in the preparation of this paper. LITERATURE CITED

(1) Am. Assoc. of Textile Chem. and Colorists, 1943 Year Book, Vol. XX, pp. 223-6. (2) Hock and McMurdie, J. Research Natl. Bur. StandardJ, 31 (Oct. 1943). (3) Husemann, E., J. makromolekulare Chem., 1, 16-27 (Aug., 1943). PRESENTED before the Diviaion of Cellulose Chemistry at the 108th Meeting of the AMERICAN CHEMICAL SOCIETT in New York, N. Y.

Thermal Conductivity of Alcohols and Glycols J

0. KENNETH BATES AND GEORGE HAZZARD The S t . Lawrence University, Canton, N. Y .

T

HE apparatus and experimental procedure used in these determinations were fully described in previous papers ( I , $ , 3). Since problems relating to experimental procedure and precision of results were discussed in these articles, this paper will present only experimental results of the thermal conductivity and the temperature coefficient of thermal conductivity of industrial nbutyl and n-amyl alcohols, and water mixtures of industrial ethylene glycol, propylene glycol, and n-propyl alcoholl. Most of this information has been unavailable in scientific literature. Tables I and I1 present the experimental data. Since n-amyl alcohol is completely immiscible in water and n-butyl alcohol is miscible only up to 8 per cent alcohol, only values for the pure liquids are given. The data in the tables cover the temperature 1 This paper was originally accepted in January, 1943, but was withheld from publication at that time at the request of the Government oeneor. Restrictions have now been removed for the presentation of these data.

range over which tests were made. Within this range the precision of the data is one per cent. Figures 1 and 2 present graphically the variation of thermal conductivity with composition. Figure 1 shows the greater conductivity at 50" C. of water mixtures of ethylene glycol than of water mixtures of propylene glycol as well as the interesting point of inflection at 6 per cent propylene glycol. Figure 2 gives the variation of conductivity with composition of n-propyl alcohol-water mixtures at 50' C. and shows a similar point of inflection a t 6 per cent n-propyl alcohol. These points of inflection were checked a great number of times, particularly in the range from pure water to 10 per cent n-propyl alcohol or propylene glycol. Such points should provide an interesting basis for theoretical work and probably exist in many other liquid mixtures. The physical properties of the liquids tested, all of technical grade, were supplied by the manufacturer in each case and are listed in Table 111. The thermal conductivity of the first five alcohols in the normal series is presented in Table I V and compared with published values of other investigators. There seems to be decreasing conductivity with increasing molecular weight.

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INDUSTRIAL AND ENGINEERING CHEMISTRY

Vol. 37, No. 2

TABLE I. THERMAL CONDUCTIVITY OF AQUEOUS GLYCOL MIXTURES 200 c. 100 90 80

70 60

50 40 30 20 10 O C

0.000690 0.000745 0.000800 0.000860 0,000925 0.001000 0.001075 0.001160 0.001250 0.001345 0,001460

30' C. 0.000670 0.000725 0.000785 0,000850 0,000920 0.001000 0.001085 0.001175 0,001270 0,001370 0.001480

K L .Gram-Cal., Sec. -1, Cm.-z, C. -1, Cm.a-50' C. 60' C. 70' C. 80' C.

40' C .

Ethylene Glycol-Water Mixtures 0.000635 0.000615 0 000600 0.000580 0.000650 0 000665 0.000695 0.000645 0.000760 0.000745 0 000735 0.000720 0.000830 0,000820 0 000810 0.000800 0.000910 0,000905 0 000900 0.000896 0.001000 0.001000 0 001000 0,001000 0.001095 0.001100 0 001105 0.001115 0.001230 0 001220 0.001195 0.001205 0.001305 0.001325 0 001340 0 001360 0 001460 o.ooi415 0.001440 0 001485 0.001630 0 001540 0.001570 0 001600

0.000655 0.000710 0.000776 0.000840 0,000915 0.001000 0,001090 0.001185 0.001285 0.001390 0.001510

Propylene Glycol-Water Mixtures 100 0.000476 0.000450 90 0 000540 0.000515 80 0.000615 0,000595 70 0.000695 0.000675 60 0.000790 0.000775 50 0.000900 0,000895 40 0.001020 0,001015 0 001015 30 0.001140 0 001155 0.001065 20 0.001290 0 001310 0.001330 10 0.001440 0 001470 0.001500 a Multiply by 2900 t o convert t o B.t.u., hr. -1, ft. - 3 O F - 1 in b aaois defined by Kr = Kaofl asa(t 50)I when is meaburkd in ' C. c Pure water. d Pure promlene glycol a t 120' C., 0.000405.

+

-

PERCENT

1000 c.

0 000565 0 000630 0 000710 0 000790 0 000890 0 001000 0 001120

1100

aub

-0.28

-0 23 -0 166

0.000686 0.000770

... ... ... ...

0.000

+O 056

...

4-0.136 i o 166

... .

.

+0.095

I

...

...

,..

120 -0 066

...

0.000420d 0.000485 0,000565

0 001020

-a

... ...

0.000430 0.000495 0.000575 0.000655 0.000765

...

cl-I

%,a

0.000525 0.000600

... ... ...

0 000440 0 000505 0 000585 0 000665 0 000770 0 000895

--c.

...

...

+o

20

-0 -0 -0 -0 -Q

38 20 166 140

080 -0.020 +0.030 +0.100 4-0 k60

...

i o 21

i

T.4BLE

Results are presented on determin a t i o n s of t h e thermal conductivity and the temperature coefficient of thermal conductivity for industrial n-butyl alcohol and n-amyl alcohol and for water mixtures of industrial ethylene glycol, propylene glycol, and n-propyl alcohol.

900 c.

.iloohol, :A by W t .

100 90 80

70 60

50 40 30 20 10 100

20' C.

11. THERMAL COSDUCTIVITY

O F .kLCOHOLS

Kt, Gram-Cal., Set.-:, ern.-*, ' C.-1, Cm.a 40' C. 50' C. 60' C. 70" C.

30' C.

n-Propyl Alcohol-Water Mixtures 0.000395 0.000380 0.000360 0.000345 0.000330 0.000310 0.000420 0.000410 0.000395 0.000385 0.000375 0.000360 0.000470 0.000460 0.000450 0.000440 0.000430 0.000420 0.000535 0.000525 0.000620 0.000510 0.000500 0.000496 0.000610 0.000600 0.000595 0.000590 0.000585 0.000580 0.000710 0.000705 0.000700 0.000695 0.000690 0.000685 0.000830 0.000530 0.000825 0.000825 0.000825 0.000820 0.000965 0.000970 0.000970 0.000975 0.000980 0.000980 0 001105 0.001120 0.001130 0.001145 0.001160 0.001170 0.001285 0.001310 0.001330 0.001355 0.001380 0.001400

7

80" C.

90' C.

0.000295 0.000280 -0 0.000350 ... -0 0.000410 -0 0.000485 -0 0.000570 -0 0.000680 ... -0 0.000820 ... -0 0.000985 ... 4-0 0.001185 ... +O 0.001425 ... +5

... ... ...

n-ButJ 1 Alcohol 0 000375 0 000365 0 000360 0 000350 0 000340 0 000335 0 000325 0 000320

n-Amj 1 Alcohol 100 0 000375 0 000365 0 000355 0 000345 0 000335 0 000325 0 000315 0 000305 a Multiply by 2900 t o convert t o B.t.u., hr.-I, ft.-*, F.-l, in. b is defined by Kt = Kso[l aso(t 5011 when t i s measured in O C .

+

GLYCOL

Figure 1. Variation in Thermal Conductivity with Composition of Glycol-Water Mixtures

aub,

70,"C.-I 48 32 22 160 100

070 025 036 115

1i5

-0 23

-Q 28

-

PERCENT N-PROPYL ALCOHOL Figure 2. Variation in Thermal Conductivity with Cornposition of n-Propyl Alcohol-Water Mixtures at 50' C .

INDUSTRIAL AND ENGINEERING CHEMISTRY

February, 1945

TABL 111. ~ PHYSICAL PROPERTIES Formula

Mol. wt. B,P,(1 stm.), 4C. Sp. gr. TABLE

Ethylene Glycol CHiOH &+OH 62.06 197.2 1.1176d:~

Iv.

Alcohol Methyl Ethyl n-Propyl n-Butyl n-Amyl

Pro ylene Ggcol CHsCHOH

n-Butyl n-Propyl Aloohol Alcohol w-CSHTOH n-CaHoOH

d H 2 o ~ 76.06 60.06

187.4 97.2 1.038ld~~ 0.804d:'

n-Amyl Alcohol n-CrHltOH

117.7 0.8109d::

137.9 0.817d:X

THERMAL CONDUCTIVITY OF NORMALAmonoL SERIES AT 30' C. Bates et al. 0.00050 3) 0.00041 ti??) 0.000380 0.000365 0.000365

ing the past few years on water under many different experimental conditions, and the values reported are the best we have determined up to the present time. ACKNOWLEDGMENT

88.09

74.12

Others

195

Acknowledgment is made to the Carbide and Carbon Chemicals Corporation for supplying the necessary ethylene and propylene glycol and the n-butyl alcohol; to E. I. du Pont de Nemours & Company, Inc., for the n-propyl alcohol; and to the Sharples Solvents Corporation for the n-amyl alcohol. We also wish to express appreciation to Gerald Palmer for his assistance with some of the liquids. LITERATURE CITED

Table I indicates that the thermal conductivity of water is about one per cent higher a t 50' C. than was previously reported (3). We have made several hundred determinations dur-

(1) Bates, IND. ENQ.C E I ~ M25, . , 431 (1933). (2) Ib$d., 28, 494 (1936). (3) Bates, Hazaard, and Palmer, IND.ENQ.CHEM.,ANAL.ED., 10, 314 (1938). (4) Bridgman, Proc. A m . A m d . Arts Sci., 59, 141 (1923). (5) Daniloff, M., J . Am. Chem. Soc., 54, 1328 (1932). (6) Smith, J. F. D., IND. ENO.CHEIM., 22, 1246 (1930).

Nature of Asphaltic Substances DONALD L. KATZ AND KARL E. BEU' University of Michigan, Ann Arbor, Mich.

A

Thin films of asphalt and oil have been exSPHALTIC bitumens are a or asphaltene, contains soot and graamined i n the electron microscope in a search product of crude oil and somephitic carbon. The resinous matefor colloidal asphaltene particles. These films times occur in a concentrated form rials are believed to be protective seem to be free from particles, but numerous as a residuum of petroleum deposits. colloias for the micelles. The addiparticles appear when suspensions of asphalt These asphaltic bitumens may be tion of liquids, which have a surface in benzene and petroleum ether are examined. retained in the fuel oil after refining tension below about 24 dynes per Micrographs at 156,000 diameters indicate processes, or may be concentrated centimeter at 25" C., causes flocculaasphaltene particles, if present in undiluted for use in asphalt paving. Until tionof the micelle, while the addition oils and asphalt, are less than 65 A. in diameter. they were found to precipitate of liquids having a surface tension from the crude oil a t the time above 26 dynes per em. causes peptiof production, mention of the term zation, according to Nellensteyn (8). "asphaltic bitumen'' would bring to mind the concentrated form Swanson (13) separated asphalt into the three substances and used for road construction. presented data indicating that the resins could be used to peptize The peculiar nature of the precipitation of bitumen from a the asphaltene when in sufficient cpncentration; he gave photoCalifornia well producing from 11,000 feet raised questions congraphs to show the disappearance of particles of asphaltene. cerning the nature of the precipitation process and of the physical Traxler and Coombs (1.4) demonstrated the thixotropic properties state of the asphaltic bitumen prior to precipitation. The elecof asphalt, which further substantiate the colloidal nature of the tron microscope has been found a useful tool in making studies materials. Benson (8) showed coagulation in thin films of asof the physical state of asphaltic substances (11). Crude oile phalt. have been examined for the presence of the asphaltic bitumen by Williford (16) presented x-ray diffraction patterns for several the electron microscope. Also, a series of samples a t successive asphalts and correlated these patterns with some physical propstages in the manufacture from the crude oil, topped crude, reerties. duced crude, through various grades of asphalt have been exPRECIPITATION DURING CRUDE OIL PRODUCTION amined by the electron microscope. The formation of bitumens by the flow of oil through sand has been related to the electrical The occurrence of asphaltic bitumen granules in an oil and gas flow potential caused by the flow of the oil through the porous separator in California on a well producing from the Vedder zone solid. These experiments have given a concept of the state of of the Greeley Field raised a new problem in the behavior of asthe asphaltic substances in crude oil and refined products, which that the addiphaltic bitumen (11). It had been known (6,6,15) is somewhat at variance from the views previously held. tion of volatile hydrocarbons would cause the separation of the The theoretical aspects of asphaltic bitumen have been treated asphaltic constituent from crude oil, but no reports indicated by numerous authors (1, 7, 8, 9, 10, 13, 14). I n general, they that the removal of dissolved hydrocarbons from a crude oil agree that asphalts are composed of three types of materials: would precipitate the asphaltic bitumens. the colloidal asphaltic bitumen micelles, asphaltic resins, and an Further investigation of the problem revealed that asphaltic oil. Xellensteyn (8) asserts that the asphaltic bitumen micelle, bitumen was deposited in the tubing of the well, and that the pressure a t the bottom of the well was in excess of the bubble1 Present address, Phillips Petroleum Company, Bartlesville, Okla.