INDUSTRIAL AND E N G I N E E R I N G CHEiMISTRY
1010
from July, 1931, to date; for the month of January, 1932, it had reached 314 tons of cellulose, 439 tom of fine papers, 54 tons of hydrochloric acid, 82 tons of caustic soda (for sale), and 115 tons of refined table salt (for sale). Based on these January figures, the yield of cellulose has been 45 per cent on the basis of wheat straw used, and the cost has been 17.49 paper pesos’ per 100 kg. This compares with a market price of 24 to 25 paper pesos per 100 kg. for imported bleached wood cellulose delivered a t Rosario. The cost of paper of fine quality was 34.29 paper pesos per 100 kg. and the types based on straw cellulose have a good market in Argentina. Other plants are being planned to apply the Pomilio process, one in Chile for treating wheat straw, one in Brazil using rice and other straws, and others in Europe.
COXCLL-SION Despite the fact that fifteen years have been spent in developing the chlorine process, much remains to be done, and it is apparent that it is now only a t the beginning of its industrial expansion. It links three great industrieshydroelectric chlorine, cellulose, and paper-and its future depends on bringing these three into closer cooperation. The value of the chlorine process is enhanced by the fact that i t is especially suited for the treatment of annual straws for the production of fine papers without increasing the
Vol. 24, No. 9
demand upon wood resources as the growing demands of civilization require larger and larger quantities of cellulose and paper. Despite the conviction of many paper makers that only wood cellulose can produce satisfactory papers, the Rosario development has amply demonstrated that these are easily made from 100 per cent straw cellulose to meet all demands of the market. The chlorine process offers an outlet for some of the excess hydroelectric energy of those countries where power development has exceeded demand. Its application is unquestionably desirable in those countries when suitable vegetable fibers and salt can be cheaply obtained, since energy is an important economic factor in the cost of cellulose made by this process. Those countries having large productions of cereal straws (Argentina, Canada, Russia, the United States, Australia, etc.), or of rice (Japan, China, Brazil, Spain, Italy, etc.), or of esparto (Spain and North America), have in the chlorine process a potential method of recovering a valuable agricultural waste of considerable economic importance. LITERATURE CITED (1) Cross and Bevan, “Cellulose,” Longmans, 1918; “Text Book of Paper Making,” 5th ed., E. & F. iY.Spon, London, 1920. (2) Pomilio, Chimie & industrie, 6 , 267 (1921); 8, 41 (1922); 11, 423 (1924). RECEIVED June 2, 1932.
Hydrogenation of American Coals W. L. BEUSCHLEIX AKD C. C. WRIGHT,University of Washington, Seattle, Wash.
T
HE pioneering work of Bergius on high-pressure coal hydrogenation has opened to chemists a new and profitable field for research. The major portion of the literature thus developed appears in the form of patents claiming distinctive merits for some particular type of equipment, method of operation, or catalyst, but making little or no mention of the type of coal used. Fundamental researches on the mechanism of hydrogenation, and upon the relationships existing between hydrogenation and constitution, however, have been conducted by several investigators, among whom may be mentioned Arend ( I ) , Kling and Florentin ( 5 ) , and Graham (4). I n these latter researches many coals from widely separated sources have been investigated, and much valuable information has been made available to the scientific investigator and to the industry. Commercial methods of hydrogenation involve treating the coal in a dispersion medium of saturated oil with hydrogen a t high pressure and a t temperatures between 450” and 550’ C.; the separation of products is based for the most part on distillation. Investigators in the theoretical field have usually resorted to phenol or some similar, easily removed dis-
persion medium; they have separated the products by methods based upon extraction in order to eliminate the effect of cracking coincident with distillation. It is the purpose of this investigation (1) to effect a correlation between the commercial and theoretical methods by hydrogenation studies on a series of American coals when dispersed in both type of media, and (2) to show the relationships existing between the degree of hydrogenation and the ranking of the coal according to the more common methods of classification. This paper will deal with the investigations in which phenol was the dispersion medium.
INSTALLATION AND EXPERIMENTAL METHODS A detailed description of the laboratory installation, the method of operation, and the separation of the products has appeared in a previous publication (2); a brief summary follows: The reaction chamber (0.3 liter capacity) is of the stationary type, employing no stirring, and is heated electrically by means of external coils. A thermocouple well is immersed directly in the charge, and temperatures are determined by means of a thermocouple and pyrometer. Con-
TABLEI. DESCRIPTION OF COALS STATE
COUNTS
Washington Washington Alabama Pennsylvania West Virginia Kentucky Washington Illinois Washington TTtah iv&ington Washington Washington Washington
Pierce Pierce Jefferson Allegheny Logan Letcher Kittitas Franklin King Carbon Kittitas King Thurston Lewis
SAMPLE 2 3 11 13 12 10 14 9 4 fi
i
5 7 8
BED
5 7 Mary Lee Pittsburgh Chilton Elkhorn Roslyn Illinois 6 2 Castle Gat e Roslyn Jones 1
Foron
PROXIMATE ANALYSES A S RECEIVED Volatile Fixed MINE Moisture matter carbon -4sh % .. % % % 10.8 2.0 23.9 63.3 Fairfax 8.1 26.8 63.7 1.4 Wilkeson 8.3 59.9 4.2 27.6 Flat T o p 7.5 34.2 56.7 1.6 Ocean 2 4.3 57.9 1.3 36.5 Boone 2 2.2 59.0 2.2 36.6 204 11.2 2.8 38.3 47.7 Roslyn 3 12.3 32.1 47.7 7.9 Orient 1 14.1 46.9 35.1 3.9 Occidental 49.1 7.1 40.9 2.9 Rolapp 12.2 43.5 38.8 5.5 Roslyn 7 44.4 5.4 38.2 New Black Diamond 1 2 . 0 39.3 5.8 33.9 21.0 Tono 7.6 32.4 30.8 29.2 Ford’s Prairie
--ABHS
ULTIMATE ANALYSES, A N D MOISTURE-FREEH C N 0
% ..
%
%
%
%
0.5 0.4 0.9 1.2 0.6 0.6 0.5 1.0 0.8 0.5 0.6 0.4 0.5 0.9
5.4 5.5 5.3 5.7 5.5 6.1 6.3 5.3 5.8 5.9 6.2 5.7 5.6 5.6
88.1 87.7 87.1 85.6 84.8 84.6 82.6 82.2 81.3 81.1
2.6 2.5 1.8 1.8 1.7 1.6 2.1 1.7 1.6 1.5 1.7 2.0 1.5 1.3
3.4 3.9 4.9 5.7 7.4 7.1 8.5 9.8 10.5 11.0 11.5 14.8 18.5 20.5
80.0
77.1 73.9 71.7
September, 1932
INDUSTRIAL AND ENGINEERING CHEMISTRY
stant-pressure experiments are made possible by means of a 50-liter buffer bottle maintained a t the desired pressure. The charge, a 1:l mixture of coal (-60 mesh) and phenol, is placed in the reaction cylinder and maintained a t the desired temperature and pressure for 8 hours. No added catalysts are used. The products are separated, according to the method of Graham, into the following fractions:
1011
coals contain humic acids that are soluble in the hydroxide solution used for removal of phenol. For these coals no distinction has been made between phenol-insoluble fractions and the portion insoluble in both phenol and aqueous solutions of sodium hydroxide.
A . Insoluble in phenol B. Soluble in phenol and insoluble in chloroform C. Soluble in phenol and soluble in chloroform
D. Light oil boiling below 150' C. E. Water F. Gas
I n a paper ( 2 ) dealing with the preliminary study of temperature and pressure conditions for coal hydrogenation in a phenol dispersion medium, it was shown that optimum conversions were obtained, for the two coals investigated, a t a temperature of 350" C. and a pressure of 211 kg. per sq. cm. (3000 pounds per square inch). I n lieu of more specific data for the coals under investigation, it was decided that these conditions should be maintained throughout the present series of experiments. Selection of samples for this investigation was SA~IPLES. determined by the desirability (1) of obtaining a series of coals varying in rank from a IQw-grade sub-bituminous to a semi-bituminous, and (2) of obtaining a number of samples of similar rank from widely separated sources. The first requirement was satisfied by eight Washington coals, and the second, by samples procured from six other states. Table I presents a description of the samples, including proximate and ultimate analyses. In Table I1 are shown the classifications of these coals according to Campbell (3) and Seyler
I
-TO
Phenol extractions of the raw coals gave the results presented in Table 111, which includes the carbon: hydrogen ratios of the A and B fractions. I n examining these data, it is to be noted that the quantity (100 per cent minus percentage A fraction) does not in a11 cases represent the percentage of coal soluble in phenol. The low-ranking (sub-bituminous)
SAMPLE
COhL
CLASSIFICATION O F COALS
-
--CLASSIFICATIOX Campbell's
CARBOS, --FIXED CARBOX.ha- .AND Ash- and As received, MOIRTURE-FREE moisture-free ash-free
Seyler's
% 9
3 11 13 1'
10 14 9 4 6 1
5
k
Fairfax, Wash. Wilkeson, Wash. Flat Top, Ala. Ocean 2 , P a . Boone 2, W.Va. 204, Ky. Roslyn 3, Wash. Orient 1, Ill. Occidental, Wash. Rolapp, Utah Roslyn 7, Wash. New Black Diamond, Wash. Tono, Wash. Ford's Prairie. Wash.
100
Product
Similar data for the hydrogenation experiments are presented in Table IV. With those hydrogenated coals yielding large percentages of B , difficulties were encountered in removing sodium phenolate and sodium hydroxide from the mixture of precipitated B and C fractions. The high yields reported for coals 2, 3, and 14 may be accounted for in this manner. However, errors in the determination of B do not affect the percentages of A and C.
RESULTS OF HYDROGENATION
11.
-%A
FIGURE1. PERCEXTAGE HYDROGENATION us. PERCENTAGE CARBONA N D FIXED CARBON
(6).
TABLlC
80
60
/UU
Semi-bituminous Bituminous Bituminous Bituminous Bituminous Bituminous Bituminous Bituminous Bituminous Bituminous Bituminous Bituminous Sub-bituminous Sub-bituminous
o-Bituminous o-Bituminous o-Bituminous p-Bituminous m-Lignitous per-m-Lignitous per-m-Lignitous m-Lignitous m-Lignitous m-Lignitous per-o-Lignitous o-Lignitous H a r d lignite Medium fat earthy lignite
%
%
88.1 87.7 87.1 85.4 85.2 84.4 82.6 82.2 81.3 81.1 80.0 77.1 73.9 71.7
TABLE 111. EXTRACTIOX OF ORIGINAL COALS. SAMPLE 2 3
COAL
--
CARBON
B
C
A
%
%
%
%
6.3 5.2 2.0 10 '2 12 3 5.1 7.6
0.9 0.9 0.7 3.7 7.4 6.2 5.4 2.5
87.3 87.2 86.4 81.8 83.9 81.6 79.0 80.5 z8.8 ,9.0 77.6 75.3 71.3 69.7
Fairfax, Wash 93.0 Kilkeson, TJ-ash 93.9 Flat Top, Ala 97.4 13 Ocean 2, Pa 86.1 Boone 2, If' Va 12 81.0 10 204, K y 89.5 14 Roslyn 3, Wash 85.1 Orient 1, Ill 9 85.6 4 Occidental, Wash 89.2 Rolapp, Utah 6 82.7 1 Roslyn 7, Wash 89.4 New Black Diamond, Wash. 88.0 ! Tono, Wash 60.9 ;1 Ford's Prairie, Wash 50.0 a .I11 results reported on ash- and moisture-free basis. 11
lpR.ACTIOXS-
A
11 1
2.7 6.7 5.3 0.9 0 6 1.1
2 .o 6.1
4.5 0.4 1.9 1.8
B %
82.7 82.6 80'3 81,4 81.0
78.1 81.4 79.4 z9.6 (7.8
..
HYDROQEX A B
%
%
5.1 5.2 5.2 4.7 5.0 4.7 5.2 4.5 5.0
4.2 4.3
4.6 4.9
5.3 4.8 4.9 5.1
... ...
5.2
...
4.8
4.9 4.6 5.1 5.2 5.1
...
C : H RATIO A B 17.1 16.8
19.7 19.2
I N D U S T R I A L A N D E N G I NE E R I N G
1012
C H E 21 I S T R Y
TABLETV. EXTRACTION OF HunIROGENATED A
COAL
'PRODUCTR-
%
0
%
C %
63.8 79.7 37.5 51.9 26.0 32.6 63.6 45.4 35.1 18.3 21.7 13.2 8.4 8.1
32.0 23.4 44.3 29.: 28.t 31.7 16.5 18.7 21.7 26.5 31.9 12.8 24.2 18.4
B
Fairfax, W a & 16.4 Wilkeson, Wash. 9.7 Flat Top, Ala. 18.2 Ocean 2, Pa. 17.6 Boone 2, W. Va. 38.8 204, K y . 28.2 Roslyn 3 Wash. 17.9 Orient 1 '111. 27.2 Occidenth, Wash. 32.3 Rolapp Utah 42.7 Roslyn'7 Wash. 39.7 New Blahk Diamond, Wash. 49.9 Tono Wash. 40 0 Ford& Prairie, Wash. 45.4 All results reported on ash- and moisture-free basis.
An examination of the percentages of A shown in Tables I11 and IV indicates that no simple relationship exists between the amounts of these phenol-insoluble fractions before and after hydrogenation. Furthermore, it is not possible to predict from a study of the B and C fractions in the original coal the relative proportions of these same fractions resulting from the hydrogenation.
I
I-
A
COA.Lsa
CARBON
%
86 8
Vol. 24, No. 9
B %
84 1
HYDROQEN A B
%
%
3.8 4.5 3.8 4.0 3.7 3.7 4.5 3.3 4.0 3.6 3.8 3.6 3.7 4.0
4.5 4.5 4.4 4.3 4.3 4.3 4.5 4.2 4.4 4.3 4.5 4.2 4.6 4.2
C : H RATIO A B
scissas. The percentage conversion is defined as the percentage of the coal converted into phenol-soluble products by hydrogenation, or, mathematically expressed: Percentage conversion = (100 - X ) - (100 - Y)= Y - X where X = percentage A from hydrogenated sample Y = percentage A from phenol-extracted sample of raw coal Other relationships investigated, but not reported because of the negative results obtained, include moisture, oxygen, carbon: hydrogen ratio, carbon:(hydrogen minus one-eighth oxygen) ratio, and fuel ratio. An examination of the six curves plotted in Figures 1 and 2 shows that the best interpretation of results is obtained in curve 4,Figure 2, in which percentage conversion is plotted against percentage carbon (both on ash- and moisture-free basis). The remaining curves, although indicating the general trend toward lower conversions with the low-ranking coals, do not correlate the data as satisfactorily. I n curve 4 sample 12 (Boone 2 coal) shows an unexpectedly low conversion. This particular coal also showed an abnormally high solubility in phenol. Further investigations on this sample will be necessary before a satisfactory explanation can be offered. Kotwithstanding the behavior of the Boone 2 coal, however, eurve 4 tends to indicate that a simple linear relationship holds between the conversion of the coal by hydrogenation and the percentage carbon in the coal.
SUMMARY
0
so
25
X
71
Convcrson
FIGURE 2. PERCENTAGE CONVERSION vs. PERCENTAGE CARBONAND FIXEDCARBON
A recent paper by Graham (4)presents the results of a series of investigations on the hydrogenation of British coals. He showed that, for the data obtained, a plot of percentage A against percentage carbon, both on the ash- and moisturefree basis, gave the best correlation between the degree of hydrogenation and the constitution of the coal. Such a graph, however, did not give entirely satisfactory results, since three separate curves were obtained indicating three different series of coals. Other data did not in all cases warrant such a grouping. Further relationships tested by Graham include the plotting of percentage residue against carbon :hydrogen ratio, carbon :(hydrogen minus one-eighth oxygen) ratio, moisture, and oxygen, none of which showed satisfactory results. Figure 1 shows a series of curves in which percentage hydrogenation, measured by the quantity (100 per cent minus percentage A ), is plotted against percentage carbon, percentage fixed carbon (ash- and moisture-free), and percentage fixed carbon (as received, ash-free). I n Figure 2 is shown a similar series of curves having percentage conrersion as ab-
Extraction studies are presented for a series of American coals before and after hydrogenation. Progressive decreases in percentage conversions have been indicated for coals of decreasing carbon contents. For the coals investigated, a linear relationship has been shown to exist between the percentage conversion due to hydrogenation and the percentage carbon of the original coal. Seemingly, the ratios of the B and C fractions in the original coals give little if any indications of the ratios of these fractions after hydrogenation. ACKNOWLEDGMENT The authors are indebted to the United States Bureau of Mines from which the samples of coal were obtained, and to H. RI. Cooper of the same bureau for analyzing these samples. The investigation was made possible by a Grantin-Aid of the Kational Research Council to W. L. Beuschlein.
LITERATURE CITED (1) Arend, J. P., Proc. 2nd Intern. Conf. Bituminous Coal, 2, 486 (1928). (2) Beuschlein, W. L., Christensen, B.. and Wright, C . C . , IKD. EKG. CHEM.,24, 747 ( 1 9 3 2 ) . (3) Campbell, M.R., Proe. I s t l n t e r n . Conf. Bituminous Coal, 1926, 5 .
(4) Graham, J. I., Proc. 2nd Intern. Conf. Bituminous Coal, 2, 456 (1928).
( 5 ) Kling, A , and Florentin, D., I b i d , 2, 5 2 3 ( 1 9 2 8 ) . (6) Seyler, C. A,, "Fuel Technology and the Classification of Coal,'' Vol. 11, Fig. 11, S. Wales Inst. Eng., 1931. RECEIVED April 8, 1932.
