Oct., 1914
T H E J O U R X A L OF I N D U S T R I A L A N D ENGINEERING CHEMISTRE7
results are given in Table 111. I n relation t o these tests i t may be cited t h a t Douty and Beebel have found t h a t no change in t h e absorption value was caused b y repeated dryings and immersions. T h e mean results for each brick by each method were then calculated. Similarly t h e deviation of each result from t h e mean absorption for the brick by each method was obtained. The latter are given in t h e columns marked "Deviations from mean." The average deviation from t h e mean for each brick is also listed under the preceding heading. The average of t h e latter for all the bricks is a measure of t h e accuracy with which t h e test can be carried out. The average deviation for t h e 48 hours immersion is 0 . 2 1 per cent and for t h e boiling test 0.51 per cent, The balance used for weighing t h e bricks was accurate t o a gram. The cons t a n t error due t o weighing is, therefore, about 0.06 per cent and is t h e same for both methods. With t h e same instruments and care, results more t h a n twice as concordant may be obtained b y t h e 48 hours total immersion test t h a n b y t h e boiling test. The former being more accurate and uniform in indications is better adapted for contractual testing. The 48 hours total immersion test a t ordinary temperatures gives absorption values which uniformly and readily approach t h e same figure. This is apparently a substantiation of t h e theory t h a t t h e absorption by this method is t h a t natural and characteristic of the brick. STANDARD TESTINGLABORATORY B O A R DOF ESTIMATE A N D APPORTIONMENT NEW YORKCITY
ISOPRENE FROM COMMERCIAL TURPENTINES By CHAS: H. HERTYAND J. 0. G R A H A X Received July 27, 1914
I n connection with t h e studies of rubber made b y polymerization of isoprene, Harries and Gottlob3 described a method for t h e preparation of isoprene from spirits of turpentine b y means of t h e "isoprene lamp." I n this method t h e spirits of turpentine is boiled in a flask, in which, just below t h e neck, is suspended a n electrically heated platinum wire coiled somewhat like t h e filament of a tantalum incandescent bulb. A part of t h e vapors are decomposed as they pass upward across t h e heated wire. The flask is attached t o an upright condenser maintained at a temperature of 50" C., for condensing t h e unchanged vapors of spirits of turpentine. The upright condenser is connected with a n inclined condenser fed with t a p water and this in t u r n is connected with a receiver surrounded b y a freezing mixture. The crude product collected in this receiver is fractionated and t h e isoprene collected as t h e fraction boiling between 35" and 37" C. With this apparatus, Harries and Gottlob obtained a yield of only I per cent of isoprene from commercial pinene as against 30 t o j o per cent from commercial limonene. They, therefore, concluded t h a t t h e yield of isoprene from spirits of turpentine is due chiefly t o t h e presence of dipentene (limonene). Proc. Amer. SOC.f o r Testing MaLeuials, 11, i i 0 . 2 Presented a t the 48th Meeting of t h e American Chemical Society, Rochester.. SeDtember 8-12. 1913. . 8 Ann., 383, 228. 1
803
I n view of t h e general interest in the production of rubber from isoprene, i t seemed desirable t o extend these studies t o commercial products closely related t o spirits of turpentine and t o test further t h e point mentioned above as t o t h e origin of t h e isoprene from spirits of turpentine. Accordingly, studies have been made using commercial spirits of turpentine, fractions of t h e same, pine oil, t h e volatile oil of Pinus serotina (pond pine) and refined spruce pine turpentine. The apparatus used closely resembled t h a t of Harries and Gottlob, short-circuiting of t h e sections of red hot platinum wire being prevented b y winding t h e wire on a pipe stem triangular prism. A constant current of 2.25 amperes maintained a n even temperature of the wires a t a red glow. The flask containing t h e turpentine was heated by means of a bath of cottonseed oil containing a thermometer. The receiving vessel in t h e freezing mixture, salt and ice, was a small sulfurous acid condenser. The crude products were refined by distillation through a Hempel column filled with glass beads. The yield of pure isoprene in each of t h e experiments which follow represents the fraction collected between 3 j " and 37 " C. SPIRITS O F TURPENTINE
cc. of spirits of turpentine were boiled in t h e isoprene lamp until condensation ceased in the inclined condenser. At two-hour intervals the crude product was removed from t h e receiver and fractionated. Following this experiment, similar experiments were conducted with zoo cc. fractions of spirits of turpentine obtained b y fractionation b y means of a Young's still head. The first fraction was collected between 155' and 156' C., the pinene fraction; t h e second, between 1 6 9 " and 1 7 5 " C.; t h e third fraction from 1 7 5 ' C., up. These two last fractions should include the dipentene content of the original spirits of turpentine. The heating of the two last fractions was continued only two hours, as after t h a t time no further condensation could be observed in t h e inclined condenser. The results of t h e three experiments are shown in Table I. 200
TABLE I
--
Volume of Time distillate of TemperPer cent heating ature of Crude Refined of Substance used Hrs. oil bath Cc. Cc. isoprene 6.5 3.25 2 17.5' 17 Spirits of turpentine., 3.5 1.75 2 185' 8 1.0 0.50 Totals..
. ... . . . . ..
6 2
-
.. . .
175'
-
37 10
Fraction 155°-1560.. . 2
. ..
17.50
_ _ ,
...
180: 185
4
2i 56! 3.25
...
-
-
io3 --
11.0 6 5
5.50 3.00 2.50
103
2.00
4
Totals.. . . , . . . . 8 Fraction 169°-1750... . . 2 Fraction l i S 0 + .... , . . . 2
Volume of residue in heating flask Cc.
-1 16 1 0
0.50 ~
8.00 0.50 0 00
. .. ... ...
...
so
192 195
From t h e direct proof thus obtained it is evident t h a t the yield of isoprene from spirits of turpentine is due t o pinene, rather. t h a n t o dipentene as claimed by Harries and Gottlob. T H E V O L A T I L E OIL O F P I N U S S E R O T I S A
This substance has been studied b y Herty and Dickson' and was found t o be particularly rich in 1
J . A m . Chem. SOC.,30, 872.
804
T H E JOURNAL OF INDUSTRIAL A N D ENGINEERING CHEMISTRY
limonene. Since Harries and Gottlob obtained 30 t o 50 per cent of isoprene from commercial limonene with t h e isoprene lamp, it seemed desirable t o study this volatile oil and compare its yield with t h a t from ordinary spirits of turpentine. I n preparing t h e 'material from the oleoresin t h e difficulties formerly met with in distillation by a current of superheated steam were easily overcome by heating t h e oleoresin a t a pressure of one millimeter, the volatile oil readily passing off without any tendency t o froth in t h e flask and with largely decreased opportunity for polymerization during distillation. Table I1 gives t h e results with the isoprene lamp. TABLE I1
Volume of re$due Time Temperin of ature P Per cent heating Crude Refined heating of of flask Hrs. oil bath Cc. Cc. isoprene Cc. Volume of distillate
Substance used
2.0 2.0 2.5 2.5
Totals... . . . . . . . .
-
175'
175'
185; 185
-
6.50 4.75 11.00 11.00
-
5.0 3.0 8.0 8.0
-
2.5 1.5 4.0 4.0
-
....
.... .... -
25.0
.... 33.25 24.0 12.0 25.0 No further condensate could be obtained b y continued heating of the residue. As was t o be expected t h e yield of isoprene from this volatile oil, rich in limonene, shows a largely increased yield, practically doubled, as compared with ordinary spirits of turpentine. 9.0
PINE OIL
When resinous pine wood is finely divided and treated with steam a crude oil distils off which on fractionation yields wood spirits of turpentine and pine oil. ,Teeplel has found t h a t pine oil consists chiefly of a-terpineol. The specimen used in this work showed a t 15' C. a specific gravity of 0.9403 and a n index of refraction of 1.4901. The results with t h e isoprene lamp are given in Table 111.
-
TABLE I11 Volume of Time Temperdistillate Volume of ature Per cent of Substance heating of Crude Refined of residue used Hrs. oil bath Cc. Cc. isoprene Cc. 2 2100 15 4 2.0 ... 200 CC. of pine o i l . . . . 2 210: 10 3 1.5 ... 2 210 7 1 0.5 125
Vol. 6, No.
IO
Plant Industry ( N o . 235), reporting an analysis of t h e oil of black sage, Ramona S t a c h y o i d e s , of Southern California. This analysis accounted for 62.5 per cent of the oil (camphor, 40 per cent; cineol, 2 2 . j per cent), but t h e other constituents were not definitely identified. Since the black sage grows extensively in Southern California and might become of more or less commercial importance, it seemed t o us advisable t o continue this work, first with t h e idea of determining t h e yields of camphor and cineol a t a slightly different season of t h e year; secondly, t o definitely determine t h e other constituents, and whether or not any of t h e constituents were present in sufficient quantity t o be commercially important. Through t h e kindness of Professor C. S. hlilliken, Assistant Superintendent of University Extension of Agriculiure, several hundred pounds of leaves and twigs which had been simply snipped from t h e ends of t h e branches, were forwarded t o us from t h e University Experiment Station a t Riverside, in February. These were several weeks in transit and probably suffered some loss from exposure b u t upon distillation with steam gave a yield of oil corresponding t o 0.90 per cent of t h e weight of material used. This yield is very much higher t h a n t h a t obtained b y t h e Bureau of Plant Indust r y , who made their distillation about two months later in t h e season, while t h e plant was in bloom, and obtained a yield of only 0 . 7 5 per cent. Not only was t h e yield much greater, b u t , as might be expected, the physical constants of the oil were quite different from those obtained b y t h e Bureau of Plant Industry, as may be seen from t h e following comparison: Bureau of Plant Industry 24O 0.9144 Soecific eravitv.. ........... 30.2 rotation 1.4682 Index of refraction.. Sol. in 70 per cent alcohol.. .. Sol. in 1112-t" 3112 vol. L Acid N o . . 2.5 Ester N o . . . . . . . . . . . . . . . . . . . Solid separated On cooling t o - Z O O C . .. . . . .
..
I
............ ........ .................. -
Our determination 15' 0.8979 24.4 I . 4729 Insoluble 2.2 1.6 No solid separated
I n order t o determine approximately t h e number of constituents in t h e oil and t h e relative quantities of each, we adopted a method which has been successfully used by L. F. Hawley in "Wood Turpentines" ( F o r e s t Service B u l l e t i n , No. 105). This method consists in Totals . . . . . . . . . . . . . . . . 6 .... 32 a 4.0 125 fractionally distilling t h e oil with a Hempel column and REFINED SPRUCE PINE TURPENTINE plotting curves as follows: ( a ) Temperature of distillation against t h e perThis substance, consisting chiefly of cymene, is collected as a by-product in blowing off t h e digesters centage weight which t h e fraction distilling a t t h a t in t h e manufacture of wood pulp from spruce pine. temperature bears t o t h e total. The specimen was furnished by the A. D. Little ( b ) Specific gravity against percentage weight. (c) Index of refraction against percentage weight. Laboratory of Boston. It showed a t I j' C. a specific gravity of 0.8639 and a n index of refraction of 1.4916; B u l l e t i n 105, Forest Service, gives approximately t h e 80 per cent distilled between 171.3' and 174.9' C . : zoo following interpretation of these curves. Suppose we are dealing with t w o volatile, miscible cc. of this substance were boiled three hours in the isoprene lamp but no crude distillate could be ob- components (A) and (B), having boiling points T and TI, respectively. (A) and ( B ) are each present t o t h e served. UNIVERSITY OF NORTHCAROLINA extent of 50 per cent. If (A) had no effect on ( B ) then CHAPELHILL ___.. all of (A) would distil over before any of (B) began t o come over, and plotting t h e percentage distillate INVESTIGATIONS ON OIL OF BLACK SAGE against boiling points t h e two vertical lines A X and BY BY CHARLESE. BURKEA N D CHARLESC. SCALIOKE would result. The break in the curve would indicate Received June 22, 1914 I n 1912 a bulletin was published b y t h e Bureau of a change of composition. I n an actual distillation this complete separation is never obtained, one component 1 J. A m . Chem. Soc., 30, 413.
3
-
_
.
-
