1178
INDUSTRIAL AND ENGINEERIXG CHEMISTRY
Vol. 20, No. 11
agreement with the results given above that the voltage is tion agree with the results of this investigation. The imdirectly proportional to the pH of the solution. Taking the proved technic described here, in which the pH of the solution difference in voltage between their most acid and their most is obtained under equilibrium conditions, shows that the basic solutions, these authors found an average change of straight-line relation is maintained over the whole range in-0.067 volt for each pH with Caucasian manganese dioxide. vestigated. The check between this 70.067 and the - 0.07 of the present Holler and Ritchie found that in alkaline solutions the investigation is not so satisfactory as it seems a t first, however, voltage of the manganese dioxide and graphite increased on because when all the results of Holler and Ritchie are plotted standing. while in acid solutions the voltage decreased. This in the manner of Figure 1 a curve is obtained with some parts fact is readily explained by the findings of the present research deviating greatly from the straight line. In fact, the voltage that an acid solution becomes less acid in contact with manis nearly constant over the range from a pH of 2 to a pH of 6. ganese dioxide and graphite and an alkaline solution becomes The same results were obtained also by Martin and Hel- less alkaline. The voltage of the graphite-manganese dioxide f r e ~ h twho , ~ plotted the voltage of the manganese dioxide and electrode depends on the pH of the solution actually in congraphite mixture against the pH of the original solution, as tact with the graphite particles, and hydrogen ions are taken up by hydrated manganese dioxide or by impurities of cardetermined with a quinhydrone electrode. These results are very similar to the preliminary results bonate which may be present in the ore, thereby decreasing mentioned earlier in this communication, in which the pH of the acidity and decreasing the voltage. On the alkaline side the solution did not represent the true pH of the solution the voltage is increased because ammonia and hydroxyl ions actually in contact with the particles of manganese dioxide are absorbed from the solution. Artificial manganese dioxides vary greatly in their properand graphite. The reason for the abnormal behavior is obvious. I n the ties, depending on their method of preparation. Holler and solutions between a pH of 2 and a pH of 6 the amount of acid Ritchie reported an artificial manganese dioxide which gave is so small that it is readily taken up by the large quantity practically no difference in voltage a t the different pH’s. of manganese dioxide. With large quantities of hydrochloric I n the present investigation the voltage measurements of an acid or ammonium hydroxide the buffer capacity of the solu- artificial manganese dioxide plotted against the pH of the tions is increased to a point where the effect of the manganese solution gave a straight line and its slope was abnormally dioxide is minimized, and the pH of the solution in contact steep. The artificial product was somewhat finer than the with the manganese dioxide is more nearly equal to that of natural ores, but this fact is probably not important. The the original solution, In the more alkaline solutions the re- steeper slope may be due to ions other than tetravalent and sults of Holler and Ritchie using the pH of the original solu- trivalent manganese ions, which are present as impurities in the artificial manganese dioxide. 5 Trans. A m . Electrochem. Soc., 63 (1928).
Indene and Styrene-Crude Materials in Industrial Quantities’ Ralph L. Brown PITTSBURGH EXPERIXENT STATION, U. S. BUREAU OF MINES, PITTSBURGH, PA.
H E chemistry of indene has recently been well reviewed by Courtot,2 and as indicated by him has been much studied from a theoretical point of view. Because of its occurrence in the oils and tar obtained by the distillation of coal, indene, which occurs along with coumarone in the solvent-naphtha fraction, has been much studied by the chemists of that industry, and consequently it has appeared prominently in industrial chemical literature and patent records. This is largely due to the properties which permit of the manufacture from it of a resin usable in varnishes, paints, cements, and many other product^.^ Its use in the production of perfumes, dyes, and possibly medicines has been predicted by Courtot. It has previously been pointed out that indene is a constituent of carbureted water gas and may be found in its tar4 and in the oily condensate which collects in mains in which carbureted water gas is being distributed.6 Because of its possible industrial uses and in the interest of the dis-
T
1 Received May 17, 1928. Published by permission of the Director, U. S. Bureau of Mines. (Not subject to copyright.) 2 R e p . gln. s c i . , 84,607 (1923). 8 A comprehensive compilation of literature, patents, and uses m a y be found in Chapters 2 and 3 of “Synthetic Resins and Their Plastics” (1923). by Ellis. 4 Brown and Howard, IND.ENG. CHEY.,16, 1147 (1923). 6 Brown, Am. Gas Assocn. Monthly, 4, 435 (1922); Am. Gas Assocn., Tech. Sect., 4, 280 (1922).
semination of knowledge, this paper presents the results of some quantitative studies of carbureted water-gas condensate. The analyses are entirely typical and pay particular attention to the indene and styrene content of the oils. Although it has a large literature of theoretical studies, the existence of styrene as a constituent of carbureted watergas tar, carbureted water-gas light oil, and “holder oil,” and its occurrence in industrial quantities was first pointed out only a few years ago.6-6 Except for the incidental references, no quantitative figures have been published on the styrene potentially available for industrial uses. These uses might be in the form of synthetic chemical derivatives or possibly in the field of plastics, and the data to be presented are therefore considered potentially valuable to the public and industrialist alike. These data were taken in 1922 as basic to a research on gummy deposits in gas meters. The presence of styrene in the oils obtained by the distillation of coal and those produced in the carburetion of water gas has not been sufficiently appreciated industrially. The presence of styrene in crude motor benzene and its property of polymerizing to give gum (resin in solution) and resin (metastyrene and higher polymers) are in part the reasons why the upper boiling limit of refined motor benzene is fixed 0
7
8
Brown, Am. Gas. Assocn., Tech. Sect., 6, 1353-1406 (1924). Brown and Berger, IND. ENG.CHBM.,16, 917 (1924); 17, 168 (1925). Brown, I b i d . . 17, 920 (1925).
*
November, 1928
I,VD USTRIAL A S D E,VGli\;EERING CHEXISTRY
1179
a t 140” C . or slightly under and may perhaps enter into the possibilities starting with styrene are obviously large and the refining difficulties often met mjth industrially. The behavior supply of crude styrene is cheap and plentiful. of light solvent naphthas, their variations in physical properExperimental ties, and their “jellying” properties were rather mystifying SAMPLEs-The samples of drip oil analyzed were taken to still operators, and doubtless to plant chemists, during the World War. Particularly was that true when these personally by the writer in nearly every case. Some carnc naphthas had their source, in part a t least, in carbureted from large plants, others from small ones. They are typical Fvater-gas light oil, “drip oils” from street gas mains, and of all carbureted water-gas main condensates in composition “holder oils” from city gas holders. The plastic properties and in variation. For that portion which boils below 200” C of the polymers are utilized in pitches, road materials, and these analyses are typical likewise of holder oil or the condensate which collects in gas holders. other binders. METHODS-The samples were all filtered and freed of water. This paper presents analyses of the oily condensate which collects in gas holders and gas mains, drip or drain pots of A 100-cc. sample was distilled to determine approximately gas-distributing systems. These analyses show a styrene the amounts of resin naphthalenc and heavy oil present. If t h e s e were present in iontent up to about 15 per quantity, the material wab cent. Fractions containing distilled, usually by steam, 75 per cent styrcne may be Fractional analyses of thirteen representative samples to effect a separation of the prepared from these oils. of the oily condensate (drip oil) from carbureted wateroil. The oily distillate w a b Fl‘ith the styrene in a polymgas mains and attached appliances such as meters dried and then subjected to erized form or in the form have been presented. two or three fractional disof simple derivatives, the For fresh, dry oil the indene content is normally tillations over a H e m p e l 25 per cent of stable hyabout 35 per cent; the styrene content is about 15 per column with a 10-inch (25.4drocarbons remaining can cent. Crude supplies of either indene or styrene of cm.) bead column. Table I be separated, and this unabout 75 per cent concentration are possible; the other s h o w s t h e resultant fracd o u b t e d l y constitutes an 25 per cent is almost entirely stable aromatic hydrot i o n s a s percentages (by industrial source of crude carbons. of the entire sample. volume) styrene. Industrial supplies of crude indene and styrene The undivided fractions can be produced from the drip oil and holder oil from Amount of Styrene in Drip were again dried with stick systems distributing carbureted water gas. These Oil from Manufactured sodium hydroxide and caltwo hydrocarbons can be used i n the production of Gas cium chloride and were reresins and plastics. Styrene is commanding a n active I n 1925 more than 450 distilled if they had not reinterest in a branch of the rubber industry and its billion cubic feet of manum a i n e d colorless. They derivatives are useful in the perfume industry. I t f a c t u r e d gas n-ere distribwere titrated slowly a t from offers wide possibilities in further syntheses of deuted by the public utilities. 0” to -20” C. ( u s u a l l y rivatives i n industrial use. The present potential Of this, 71 per cent, or about about - 10” C.) with a soluannual supply is about eight million pourids of styrene 320 billion cubic feet, was of bromine in anhytion and a t least twice that of indene. c a r b u r e t e d w a t e r gas. drous c. P. carbon tetraFrom that type of gas there chloride (1 cc. = 0.30 gram is from 0.02 to 0.04 gallon of bromine). The absorpper thousand cubic feet of drip oil containing styrene as indi- tion of bromine is immediate a t first, slowing somewhat as the cated. The total estimate is thus 6.5 to 10.5 million gallons end point is reached. As an end point the natural color of of oil, of which 10 to 15 per cent is styrene. At the present a temporary slight excess of bromine which endured a t least time drip oil sells for a few cents a gallon. Pure styrene is 3 minutes was used. The identification of styrene and innow available a t $8 per 100 grams in America, but it recently dene was made through the isolation and synthesis of various (1925) cost $25 per 100 grams and the dibromide $8 the 100 derivatives, among which were: grams.9 Industrial interest has begun to be manifested From indene: (1) Dibromide, m. p., 39-40’ C. since the earlier reports of the writer’s investigations. (2) 2-bromo-3-hydroxyindan,m. p., 130-1” C. (3) 2,3 dihydroxyindan, rn. p., 156-7” C. Ellislo has stated that “the production of styrene cheaply (the trans-isomer) no doubt would bring it into immediate use in the field of From styrene: (1) Dibromide, m. p., 73-4” C. plastics.” To the writer’s knowledge one large rubber com(2) Phenylglycol, rn. p., 68” C. pany is manifestly interested in styrene and its source of (3) Metastyrene: carbon, 92.1 per cent hydrogen, 7.9 per cent supply.” The use of styrene derivatives in perfume materials (4) sym-Diphenyl-dimethylethane, m. p . , is well known. For example,12styrol alcohol is used in jas124“ C. mines; phenyl acetylethane is said by Parry to be a good (5) C6Hb.CHSCN.CH2SCN,m. p., 100’ C. perfume material, and the esters of phenylglycol are highly fragrant. The acetate has marked value in the preparation Discussion of floral bouquets in which the odor of hyacinth or jasmine Table I gives also the naphthalene content of the drip is to preponderate. The propionate is similar to the acetate and finds use in the narcissus, hyacinth, and jonquil odors. oil. “Resinified” means the percentage of polymerized styThe other esters are said to be powerful. The synthetic rene plus the resinified indene. The difference between the total of the percentage values given and 100 represents the 9 Eastman Organic Chemical Lists 18 and 14. heavy oil boiling above 200” C., present as uncracked gas 10 “Synthetic Resins and Their Plastics,” p. 305, Chemical Catalog Co., oil, tar particles, or as meter oil or meter diaphragm dressing 1923. 11 U. S.Patents, 1,541,1754,1,550,323-4;1,552,874-5;(1925);1 613,in the case of meter condensate or drainings. The percent673-4; 1,627,195 (1927). British Patents 232,909; 233,649; 236,891, ages of styrene for each fraction are expressed in terms of 243,768 (1924);Canadian Patents 261,325-6-7; 265,325-6-7-8 (1926). the total original sample. The totals for the styrene and in1* Parry, “Cyclopedia of Perfumery,” Vol. 11, P. Blakiston’s Son & dene contents are shown in the last line of Table I. The Co., 1925; Gildemeister and Hoffman, “Volatile Oils,” p. 496 (1922); Parry, “Chemistry of Essential Oils,” p. 223. distribution of unsaturation between indene and styrene in
INDUSTRIAL AND ENGINEERING CHEMISTRY
1180
Table I-Indene
O
c.
I
SAMPLE3
Vol- Sty- Inume rene dene
Vol- Sty- Inume rene dene
Vol- Sty- Inume rene dene
cc. 70 % 18.5 .. 13.7 1:O 13.0 4.8 12.2 3.6 i:8 11.5 7.5 16.8 13.5 7.6 7.1 ..
cc. cc. % % % cc. % % cc. % % cc. % % 25.0 . . 22.4 4.1 .. 7.3 15.5 16.2 3:5 . . 14.0 3:i .. 2.9 0 : e .. 4.5 0:ic 8.7 1:9 15.5 5.4 11.2 4.4 17.0 6.8 4.4 1.7 6.9 2.5 10.0 3.1 i:5 8.0 2.4 i:2 5.3 2.4 i:2 6.2 2.0 i:o 11.9 3.8 13.7 . . 8.3 4.6 . . 2.9 6.2 Trace 3.9 9.0Trace 4.9 10.5 Trace 9.0 .. 6.9 5 . 0 . . 3.4 18.ti , . 10.9 23.7 16.2 11.5 1.5 .. . . .. 7.0 .. .. 30.0 .. .. 23.5 .. 4.1.. .. 9.5 . , . . 19.4 2.3 . . 24.1 , .
.. .. .. .. ..
..
I
I
.
Naphthalene Resinified
..
SAMPLE
SAMPLE 9
8
.. ..
::
..
Total 97.2 Total, exclusive of resinified materials 11.9 11.6
..
Sty- Inume rene dene
Vol-
82.8
.. ..
..
7.7 28.4
156:6
..
..
..
69.1
,.
7.5
.. .. .. ..
..
-
89.9
4.7 16.0
SAMPLE 11
,.
.
5.3 22.1
SAMPLE12
..
0:4 3.7 7.7
.. ..
. . .. .. .. .. ..
140.7
2.9 11.8
..
2.9
8.8
..
81.0
..
..
SAMPLE7
Vol- Sty- Inume rene dene
..
3.5 .. 8.2 .. 2.0 0:3 6.7 0 : 3 .. 5 . 0 1.7 14.1 4.4 3.3 0.9 0 : 5 8.4 2.8 i:4 4.7 Trace 2.6 8.6 .. 4.8 7.2 5,7 23.0 .. 14.5 7.5 10.0 .. .. 7.5 .. 2.0 .. ..
.. ..
..
SAMPLE 6
::
SAMPLE 10
19.3 9.5 6.4 6.8 1:5 2.2 0:i 16.1 3:5 8.6 3.1 4.0 1.6 14.6 4.9 12.2 3.5 i:7 9.6 3.1 i:6 2.2 0.8 8.4 Trace 4.8 13.1 Trace 8 . 0 4.1 . . 7.9 .. 5.1 27.4 .. 18.8 13.0 .. 12.2 .. 3.0 .. .. 21.0 .. 4.8 . . 3.7 . . 6.5 . .
.. .. .. ..
Vol- Sty- Inume rene dene
SAMPLE5
..
100.4 .. . . 100.4 . . . . 97.4 . . Total Total, exclusive of resinified materials 9.4 22.8 12.0 16.7 .. 12.3 70-120 120-140 140-150 150-165 165-175 175-200
SAMPLE4 METER CONDENSATE
SAMPLE2
..
Naphthalene Resinified
and Styrene i n Drip Oil, in Percentages of Total Original Samples
SAMPLE 1
FRACTION
70-120 120-140 140-150 150-165 165-175 176-200
Vol. 20, No. 11
93.4
,.
..
Vol- Sty-
Inume rene dene
cc.
%
70
%
8.4 4.2 0 : b 8.3 3.1 i:9 7.6 2.4 i:2 6.1 12.4Trace 7.6 14.8 8.1 23.0 .. 13.6 . . . ,. 3.3 . . ..
::
::
..
80.8
.. . .. . .
..
6.423.6
10.116.1
SAMPLE13
11.8 7.2 14.5 14.9 16.4 17.1 4.8 7.8
..
i:3 .. 5.2 4.3 2:l
Trace
.. .. ..
8.3
11.8
....
7.5 20.7 94.5 . . 10.8 . ' 22.2 "
I
The degree of unsaturation for any fraction was rather the fractions boiling from 150" to 165" C. was determined for a few fiamples experimentally by fractional crystallization constant throughout all the wnples. The degree of unsaturaof the dibromides, and by taking advantage of the differential tion throughout the individual fractions is shown in Table solubility of styrene dibromide and 2,3-bromohydroxyindan I1 by two typical samples. in water. The ratio was found to be about 2 parts of styrene Table 11-Typical Limiting Values for Unsaturation of Oil Fractions to 1 of indene. FRACTION SAMPLE 1 SAMPLE 2 UNSATURATION Du& TO As a check on the ratio in the other samples, advantage was c. P e r cenl Per cent taken of the differential rate in the oxidation of styrene 120 7.1 9.3 ...... 120-140 21.5 24.7 Styrene and indene by mercuric acetate in dilute acetic acid ~olution.'~ 140-150 37.5 39.1 Styrene 150-165 47.0 50.5 Styrene and indene Figure 1 shows the rate curve for indene for the mercuric 165-175 61.6 61 0 Indene with trace of stvrene acetate solution used. SufEcient data are gi&n for styrene 175-190 66.4 78.0 Indene 190-200
58.0
65.0
Indene
Table 111-Indene and Styrene in Drip Oil-Percentages of Oil Boiling under 200' C. DRIPOIL IN TOTAL SAMPLE SAMPLE STYRENE INDENE^ Per cent Per cent Per cenl
1 2 3 4 5 6 7 8
a
Figure 1
to show that in 24 hours an approximate value for the indene present can be calculated from the mercurous acetate which has been precipitated. The styrene is often largely polymerized, but only very slightly oxidized in 24 to 30 hours. By means of this reaction-midation of indene by mercuric acetate-the ratio of 2 parts of styrene and 1 part of indene was found to be general for the 150-165" C. fraction of all the samples. It was therefore used for all the samples fractionated in the same way to estimate the styrene and indene in the 150-165O C. fraction. r
1:
Brown, Ssirncc, 61, 497 (1925).
9 10 11 12 13 These values do not include polymerized indene or styrene.
Table I11 shows the percentages of styrene and indene in that portion of the drip oil boiling below 200" C. In general, indene will run 25 to 35 per cent and styrene 10 to 15 per cent. From the data in Table I1 it is evident that fractions containing 75 per cent of indene or 35 to 40 per cent of styrene can be obtained by rough fractionation. With efficient columns a fraction containing 50 to 75 per cent of styrene is obtainable. Acknowledgment
Experimental aid by H. G. Berger, G. Thiessen, and R. D. Howard is gratefully acknowledged. A readjustment proposed by the railroads in the rates on imported fertilirerc, from South Atlantic and Gulf ports to drstinations in southern territory has been rejected by the Interstate Commerce Commission.
