1296
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
tainly takes place, as the final product contains more sulfur than the original coal. Oxidation also occurs, as the type of reagents used to produce exchange capacity are also oxidation agents, Whether or not condensation takes place cannot be fully determined until more is known about the reactions that occur during the sulfonation of coal. A class of substances produced in the activation of coal that undoubtedly has a strong bearing on the exchange capacity is the humic acids, or “organic” acids as some investigators prefer to call them. These acids are known to have exchange properties and are produced by applying oxidation methods to coal. Even air at elevated temperatures produces organic acids in coal; it is therefore reasonably certain that some of the organic acids are produced during the sulfonation of coal. Concentrated sulfuric acid is an oxidizing agent. Any correlations likely to be found between exchange capacity and some property of the coal probably will be connected to the potential organic acid content of the coal or some other factor, dependent on chemical compounds capable of being transformed into exchange materials. Sulfur may even occur linked in some of the ring structures known t o be produced in the oxidation of coal, or it may occur mostly in a radical.
Summary Seventeen samples of bituminous coals from Kentucky, Virginia, West Virginia, Alabama, and Indiana were activated for exchange capacity by treating the coal with sulfur trioxide at 150’ C. in a revolving cylinder for 3l/a to 7l/2 hours, The exchange capacity of the treated product was determined on the narrow-size fraction, -28 to +35 mesh on Tyler screens. When regenerated with the equivalent of 2.05 pounds of hydrochloric acid per cubic foot of zeolite, an exchange capacity of 9500 to 12,800 grains per cubic foot of zeolite was obtained, the highest value being on a West Virginia coal, the lowest on a Kentucky coal. However, not enough coals were studied to make any generalization BS to whether coal from one state gave a higher exchange capacity than those from other states. Complete chemical and petrographic analyses of these coals were carried out by the Coal Division of the Bureau of Mines in Pittsburgh. An attempt was made to correlate the exchange capacity of the treated coal with some physical or chemical characteristics of the coal. No correlation or even a
Vol. 33, No. 10
rough relation could be noticed between the exchange capacity and the moisture, volatile matter, carbon, hydrogen, oxygen, or sulfur content of the original coal, nor was there evidence that total sulfur in the final treated material had any direct bearing on the maximum exchange capacity.
Aclcnowledgment We wish to thank G. T. Adams for constructing the sulfonation apparatus. W. A. Selvig kindly furnished the coal samples.
Literature Cited (1) Applebaum, S. B., J . Am. Water Works Assoc., 30,947-73 (1938). (2) Applebaum, 8. B.,and Riley, Ray, IND.ENQ.CEBM.,30,80-2 (1938). (3) Broderick, 9. J., and Bogard, Dale, U. S. Bur. Mines, Repts. Investigations 3559 (1941). (4) Davis, D. E.,and Zeolite Comm., Am. Water Works Assoc., Methods of Testing Zeolites, Nov. 30, 1941. (5) Davis, J. D., Reynolds, D. A,, Sprunk, G. C., and Holmes, C. R., U. S. Bur. Mines, Tech. Paper, in press. (6) Fieldner, A. C., Davis, J. D., Reynolds, D. A., Schmidt, L. D., Brewer, R. E., Sprunk, G. C., and Holmes, C. R., Ibid., 604 (1940). (7) Fieldner, A. C., Davis, J. D., Reynolds, D. A., Selvig, W. A,, Sprunk, G. C., and Auvil, H. S., Ibid., 599 (1939). (8) Fieldner, A. C.,Davis, J. D., Selvig, W. A., Thiessen, R., Reynolds, D. A., Holmes, C. R., and Sprunk, G . C., U. S. Bur. Mines, Bull. 411 (1938). (9) Fieldner, A. C.,Davis, J. D., Thiessen, R., Selvig, W. A., Reynolds, D. A,, Brewer, R. E., and Sprunk, G. C., U. S. Bur. Mines, Tech. Paper 584 (1938). (10) Fieldner, A. C.,Davis, J. D., Thiessen, R., Selvig, W. A., Reynolds, D. A., Jung, F. W., and Sprunk, G. C., Ibid., 570 (1936). (11) Fieldner, A C., Davis, J. D., Thiessen, R., Selvig, W. A,, Reynolds, D. A,, Sprunk, G. C., and Holmes, C. R., Ibid., 572 (1937). (12) Hertzog, E.S.,and Cudworth, J. R., U. S. Bur. Mines, Repts. Investigations 3382 (1938). (13) Ibid., 3382 (1938). (14) Hertzog, E.5.. Cudworth, J. R., Selvig, W. A., and Ode, W. H., U. S. Bur. Mines, Tech. Paper 611 (1940). (15) Liebknecht, Otto (to Permutit Co.), U. S. Patent 2,191,060 (Feb. 20, 1940) (16) Riley, Ray, Paper Trade J . , 107,No. 11, 74-81 (1938). (17) Smit, Pietar (to N. V. Octrooien Maatschappij “Activit”), U. 5. Patent 2,191,063(Feb. 20, 1940). (18) Tiger, H. L., Trans. Am. Soc. Mech. Engrs., 60, Fuels Steam Power, 316-25 (1938). (19) Yoder, J. D., Combustion, 10, No. 11, 35-40 (1939). PVBLISHED by permission of the Director,
U. S. Bureau of Mines.
An Organic Residue from Bromine Purification 0. C. DERMER AND ROBERT BOATRIGHT1
.
Oklahoma Agricultural and Mechanical College, Stillwater, Okla.
L
ONG ago several studies were made on the composition of organic residues formed by the rectification of bromine manufactured from seaweed. Hermann (4) by fractional distillation and crystallization separated bromoform and a fraction he was unable to identify. (This fraction was undoubtedly dibromochloromethane, as a reconsideration of 1
Present address, Phillips Petroleum Company, Bartlesville. Okla.
Hermann’s results shows. Found: carbon, 5.44; hydrogen, 0.44; bromine (by difference), 94.12. Calculated for CHClBrt: carbon, 5.76; hydrogen, 0.47; halogen (76.74 bromine -4- 17.02 chlorine), 93.76.) Hamilton (3) found bromoform and carbon tetrabromide in another residue and suggested that they were formed by the action of bromine on the organic matter of seaweed. Shortly after, Dyson (2) substantiated Hamilton’s work and also found dibromochloromethane present. In 1935 Pryanishnikov and Il’in (9) patented a process
INDUSTRIAL AND ENGINEERING CHEMISTRY
October, 1941
for recovering bromoform from a residual mixture of bromine, bromoform, and carbon tetrabromide. The material investigated here was obtained from the Tulsa plant of the Texaco Salt Products Company, now nonexistent. This plant (10) was designed to concentrate oil well brines by evaporation, using waste heat from the adjacent refinery. After part of the salts had been removed by crystallization, the mother liquor was transferred to the storage tanks and from there charged to the bromine plant. In the storage tanks it was always possible to find a layer of oil, which was proved by analysis to be a gas oil fraction. When bromine was stripped from the brine by chlorination, this oil might undergo a variety of reactions: chlorination, bromination, halogenolysis (7), oxidation, etc. The crude bromine was condensed, separated from water by decanting, and then distilled through a fractionating column heated by introducing live steam into the lower portion. The high-boiling fractions were allowed to reflux in the column and eventually to drop out of the bottom through a trap. These fractions constitute the raw material of this study.
Fractionation The material was a dark brown oil of specific gravity 2.37, having a perceptible odor of free bromine along with the characteristic sweetish odor of brominated hydrocarbons. No separation by selective solvents was successful, but distillation under reduced pressure or preferably steam distillation proved very suitable. Upon steam distillation, three liters of crude residue initially yielded 720 ml. of organic bromides with 660 ml. of water. This ratio dropped rapidly, however, of product distilled with 1090 and after 10 hours only 24 d. ml. of water. I n all, 1640 ml. of steam-volatile oil were obtained in this run. The black viscous residue still contained about 52 per cent bromine, but since i t could not be purified, it was discarded. The steam-volatile bromides were washed with sodium bisulfite solution, dried, and fractionated through a Snyder column-the volatile bromides at atmospheric pressure and the higher-boiling portions under reduced pressure. This produced fractions in the amounts indicated in Table I.
TABLE 11. Boiling point,
C.
1297
COMPARISON OF PROPERTIES Unknown CHClBrl 117.5-118 123-5 (6); 118-20 (6);
117-9 ( 1 )
-28 -22 ( 6 ) , -32 ( I ) Melting point, C or sp. gr. dgg 2.412 d'J2.445 (6); 2.477 ( d ) 0 bromine 75.0,75.2a 76.3 (calcd.) otal halogen, mijliequivalents/g. 14.6,14.7b 14.4 (calcd.) Mol. wt. in freezing CeHe 192. I96 208 (calcd.) Refractive index 1.5468 Previously unmeasured Mol. refractivity 27.38 27.49 (calcd.), (If 5 ) Surface tension, dynes 30.62 (20' C.) Previously unmeasured Paraohor 203.2 217.6 (calcd.), (84 M.p. of derivatives, e C. 90 92.5 a B y the US; of alcoholic alkali accordin4 to Hermann (4). b B y the use of sodium in liquid ammonia, eto. c Values for atomic refractions. d Values for atomic parachors. e Triphenylmethane, made by treating the unknown with benzene and aluminum ohloride.
ns0
740 mm. pressure. Table I1 shows the evidence accumulated to prove it dibromochloromethane. FRACTION AT 145-150" C. Melting point, boiling point, and the formation of triphenylmethane in a Friedel-Crafts reaction with excess benzene proved this fraction t,o be bromoform. FRACTION AT 90-110' C. (22 Mm.). This portion, a yellow lachrymatory oil, could not be separated into any chemical individuals. It solidified to a glass in solid carbon dioxideacetone mixtures. Densities of subfractions ranged from 1.95 to 2.09 a t 20" C.; and the refractive index of one portion was 1.5370 at the same temperature. Determination of average molecular weight by depression of the freezing point of benzene gave the values 279, 284, 310. By use of the liquid ammonia method and the ultimate displacement of bromine from heated silver bromide by a stream of chlorine, several fractions were found to contain about 84 per cent bromine and 5 per cent chlorine. This ratio of seven atoms of bromine to one of chlorine would be impossible for a pure compound of the molecular weight indicated.
Aclcnowledgment The authors wish to thank H. E. Shirley for information concerning the origin of the residue.
TABLE I. FRACTIONATION OF STEAM-VOLATILE BROMIDES B. P. of Fraction, Volume,
c.
e115 115-120 120-145
6
M1.
5 850 50
B. P. of Fraation, 0
c.
145-150 90-110 (22 mm.) Residue5 (22mm.)
Volume, M1.
850 250 100
Ca. Distillation discontinued when deoomposition became peroeptible.
Identification FRACTION AT 115" C. The small size of this sample made it difficult to purify. A small vacuum-jacketed Vigreux column enabled us to isolate somewhat less than 1 ml. of material boiling at 88-104" C. This had a very sweet taste, a specific gravity of 1.93 (32'/32" C.), and a refractive index of 1.4890 at 32" C. It contained both chlorine and bromine, but the wide boiling range made quantitative analysis seem useless. Nevertheless, there is little doubt that this fraction was principally bromodichloromethane, for which the recorded constants ( l a ) are: boiling point, 90.10" C.; melting point, -57.1" C.; d", 1,9724; d16, 2.0055; and n:, 1.50120. If a molecular weight of 164 is assumed for the unknown, its molecular refractivity, MR, is 24.52; the calculated value (from the atomic refractions, 11) for bromodichloromethane is 24.57. FRACT~ON AT 115-120" C. Further fractionation yielded a sweet-tasting compound which boiled at 117.5-118" C. and
Literature Cited (1) Besson, Compt. rend., 113, 773 (1891). (2) Dyson, J. Chem. Soc., 43, 36 (1883). (3) Hamilton, Ibid., 39,48 (1881). (4) Hermann, Am., 95,211 (1855). (6) Jecobsen and Neumeister, Ber., 15, 601 (1882). (6) L e v y and Jedlicka, Ann.,249, 74 (1888). (7) McBee, Hass, and Pierson, IND. ENQ.CHEM.,33, 181 (1941). (8) Mumford and Phillips, J. Chem. SOC.,1929,2113. (9) Pryaniahnikov a n d I l k , Russian Patent 44,925 (1935). (10) Smith, IND. ENQ.CHEM.,24, 547 (1932). (11) Swietoslawski, J . Am. Chem. Soc., 42, 1946 (1929). (12) Timmermans and M a r t i n , J. chim. phys., 23, 747 (1926).
