INDUSTRIAL A X D ENGINEERING CHEMISTRY
1084
The absorption of oxygen and formation of gum in the sunlight is a n autoxidation reaction. The furction of the sunlight appears t o be to activate the oxygen absorbing compounds, as evidenced by a n induction period. The reaction then would be: A -+A ’ -+A 0 -+Polymerized acids and higher
Olefin
Activated (Autoxidation) Peroxides
aldehydes and ketones
This explanation of gum formation agrees with results of Moureu and Dufraisse (5) who studied the autoxidation of acrolein, which they found was activated b y exposure to light or b y oxygen so that i t undergoes condensation or autoxidation. I n the study of autoxidation of organic compounds, Staudinger ( 7 ) obtained compounds which he termed “moloxides,” or those compounds of unknown structure containing molecular addition of oxygen according to the Engler-Bach theory. H e also obtained known compounds termed “peroxides,” particularly of the asym-diphenylethylene, PhzC=Chz and certain ketenes, R-C=CO.
Vol. 21, No. 11
The similarity of work of the above authors and the present investigation is evident. Owing to the complexity of the composition of cracked gasoline. it is impracticable to identify the specific compounds producing the gum or undergoing autoxidation. The experimental results, however, obtained in this investigation point rather definitely that unsaturated hydrocarbons are responsible to a large degree for gum formation and t h a t those inducing the reaction through peroxide formation are probably olefins containing more than one ethenoid linkage. Literature Cited (1) Brooks, IND. ENG.CIIEM.,18, 1198 (1926). Cooke, Bur. Mines, Repis. Inseslrca!icns 2686. Dean, Bur. Mines, Tech. Paper 214. Mardles. J . Chem. S c c . , 1938,XiP. hIoureu and Dufraisse, Bu!L soc. chim., 56, 1564 (1924); C. A , , 19, 1125
(2) (31 (4) (5)
(1925). (6) Smith and Cooke, Bur. Mines, Repls. lnvesligations 2394 (September, 1922). (7) Staudinger, Ber., 58B,1075 (1025); C. A . , 19, 2658 (1923). (8) Story and Snow, IND.ISNO. CHEM.,20, 359 (1925).
Cracking of Tars from Cannel Coal’ J. C. Morrell and W. F. Faragher UNIVERSAL OIL PRODUCTS COMPANY, CEIICAGO, ILL.
ANNET, c o a l is a A crude cannel-coal tar has been cracked to give and 2.8 gallons of light oil high yields of gasoline excellently suitable for motor non-coking bitumi(recovered fronl the gas) per fuel. It is suggested that the processing of cannel ton. The yields from Lower nous coal sometimes coal can be made profitable by working UP the retort classed under oil shales. It and Upper Freeport cannel residues into solid fuels and cracking the tars into was orieinallv called “candle sh:iles were 37.5 and 38.2 coal” cecause i t c o u l d b e high yields of motor fuel. galloris of crude oil and apignited readily with a lighted prosimately 2.5 g a l l o n s of match, giving a bright flame. Cannel coal usually contains light oil recovered from the gas. substantial amounts of spores and seed coats which are beTable 11-Analyses of K e n t u c k y C a n n e l Coals from Various lieved t o yield on distillation waxes and resinous compounds. Counties VOLATILE F I X E D Before the establishment of thc petroleum industry, cannel COUNTY MATTER CARBON ASH SIiLPUR coal and shale were commercially distilled into oils and subsePer cent Per cent Per cent Per cent quently refined. JohnSon 49.130 41.920 7.150 0.802 Pike 43.400 8.3GO 0.689 46.300 The deposits of cannel coal are probably next in importance 44.160 Perry 6.000 0.766 49.400 Breathitt 66.280 3 640 0.830 29.730 to the oil shales as far as potential production is concerned, Rrea thi tt 53,800 5 540 0.722 4FJ.000 and are more important than the oil shales because they Morgan 50.060 8 400 1.650 40.140 give a larger yield of oil or t a r and a residue tJhat can be used Gentry ( 7 ) shows comparative yields of products from coal, as a solid fuel. lignite, and shale as indicated in Table 111. The cannel coal Previous Work on Analysis and Yields used in these tests was exceptionally rich in volatile matter. An analysis of a Kentucky cannel coal is shown in Table I Table 111-Yield of Products i n T e s t s of Tozer R e t o r t PRODUCT P E R BITUMINOUS CANNEL ( 2 ) , and analypes of Kentucky cannel coals from various COAL LIGNITE S H A L R COAL G H O STON S count,ies as made by the Geological Survey of Kentucky in Semi-coke, pounds 1200 Waste 1700 880.0 27.2 36.1 2 3 . 8 1 02.1 Table IT (4). Kentucky is the largest producer of cannel coal. Tar. gallons
C
Ammonium sulfate, pounds
Table I-Typical
Analysis of K e n t u c k y C a n n e l Coal Per ceiil
MoistGre., . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.3R Volatile m a t t e r . ,. . . . . . . . . . . . . . . . . . . . . . . . . 48.40 Fixed carbon. Ash... . . . . . . . . . . . . 10.49 Sulfur.. . . . . . . . . . . . 1.20 Hydrogen. . . . . . . . . . . . . . . . . . . . . . . . . Carbon (total). . . . . . . . . . . . . . . . . . . . . iiitrogen.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.16 .......................... 8.70 Oxyg 13,770 B. t. Heat‘
ti.
per lb.
The following yields of products are given by Fettke ( 6 ) : Cannel c o d (upper Kittanning) gave 50 gallons of crude oil I Received April 16, 1929. Presented before the Division of Petroleum Chemistry a t the 77th Meeting of the American Chemical Society, Columbus. Ohio, April 29 t o M a y 3, 1929.
12.1
22.0
18.5
19.1
According to Craig ( 3 ) ,cannel coal is one of the important British sources from which oil may be obtained by distillation, although the only source a t present Leirig utilized is oil shale, which is mined and retorted in Scotland. The cannel coals of Great Britain usually run high in ash-e. g., 10 t o 30 per cent-and the average yield of crude oil per ton over the whole country from the cannel coals and the torbanitic cannel coals is 34 gallons. In addition, an average yield of 30 to 40 pounds of ammonium sulfate per ton can be recovered. It is cstimated that an economic unit for cannel coal is approsimately 1000 to 2000 tons per day and that at least six such retortirig and refining works can be established witliout difficulty. These plants, according to Craig, would make approximately
INDU8TRIA.L A N D ENGINEERIXG CHEMISTRY
November, 1929
1085
400,000 tons of oil fuel per annum and 6 or 7 million gallons which neutralizes the hydrogen sulfide. If corrosion occurs, of petrol, besides intermediate oils. it may be taken care of by injection of alkaline materials or Berry and Dunst'nn ( 1 ) give the following analysis, proper- by lining the reaction chamber with a protective lining. ties, and yields of crude t a r from British cannel coal: specific gravity, 0.887 to 1.000; A. P. I. gravity, 28.0 to 10.0; sulfur, Cracking of Cannel-Coal Tar by Non-Residuum Process 0.4 to 1.1 per cent; setting point, 5" to 30" C. (41 to 86" F.); The equipment used was a cylindrical still 8 inches (20 mater, after partial separation, 1 to 4 per cent; calorific value em.) in diameter and 32 inches (81 em.) lons rvith v a p x line, of dry oil, 9550 to 9655 calories per gram (17,100 to 17,379 dephlegmator, condenser, and receiver all operated under B. t. u. per pound). The following fractions are ohtainable by prcssure. The still and method of operation will be described refining: benzine, approximately 3 per cent, haviiig a specific in detail in a later publication. gravity of 0.740 to 0.750 (A. 1.' I. gravity, 50.7" to 57.1") and The cannel-coal tar was cracked a t a pressure of 125 pounds a final boi!ing point of 170" C. (338" F.);intermediate oil, per square inch (8.54 kg. per sq. em.) by the non-rcsiduum approximately 12 per cent, with a specific gravity of 0.800 process, producing without any recycling of pressurc-distil(A. P. 1. gravity 45.3") and flash point of 27" C. (80' F.) late bottoms 76.8 per cent of pressure distillate and 23.2 per (the intermediate oil would be an exccllent light fuel for traccent of coke and gas, including the loss. tors, etc.); navy fuel oil, approximately 50 to 60 per ccnt, with a specific gravity of 0.870 (-4. P. I. gravity 31.1"),fl:ish point above i i " C. (170" F.) and setting point 1,eloiv 4" C. (25" F.); parnf3n scale, variab!e, averaging 3 to 4 per cent,; pitch, hard or soft as required, more bituminous than coultar pitch, and a t the worst, mixed with oil, mould serve as a works fuel. Tropsch (8) shows the yield of t,ar and the content of plienols in the crude tar from various coals as indicated in Table IV. P h e n o l s , a n d Paraffin Obtainable from Various Coals YIELD OF I'HENOLS I N K I N DOF COAL CRUDE TAR C'RUDIC T A R Per cenl Per cenl Schwel (Central 24.0 15 Rhenish trown coal 7.6 37 U'esterwalil lignite 2.7 57 American brown (N. D.) 5.6 45 Gas name 10-14 40-45 (:AS 5-8 25-35 Fat . 3-4 15-25 Lean 1.5 0 Cannel 29.0 5-10 A kind of lignite rich in volatile matter. Table IV-Tar,
Judging by all reported work, the t a r from cannel coal more nearly approaches petroleum in composition than do the lowtemperature and high-temperature coal tars. Analysis Cannel-Coal Tar Used in Experimental Work
The crude cannel-coal t a r used in this work was derived from Kentucky cannel coal. The t a r had properties shown in Table V. Table V-Analysis of Cracking Stock (100 cc. Eneler distillation)
Cold t e s t . . . . . . . . . . . . . . . . . . . . . . . . . ......... Durol viscosity a t 50' C. (122O F . ) .. . . . . . . . . . 15 seconds B. S . (bebzene-centriluge). . . . . . . . . . . . . . . . . . . 0 . 2 per cent
20 30
40 50 60
70 80 90 E. P
20 30 40 50 P E R CENT B E N Z f N f I N P E N N A SrR4lGHT R U V GASOLjNE
60
The prcssure distillate contained 14 per cent of t a r acids, which were extracted with alkali prior to distillation through a Hempel column. The yield of the tar-mid-free pressure distillate was 66.0 per cent and of the extracted t a r acids, 10.8 per cent. The tar-acid-free pressure distillate was distilled through a Hempel column into the products shown in Table VI. Table VI-Analysis of Tar-Acid-Free Pressure D i s t i l l a t e (800 cc. Hempel distillation! Sp. g r . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0. I 981 (A. P. I.. 46.8") I. B. P . . ............................. 40" C. (104'F.j OVER Per cenl
TEMPERATURE
c.
' P.
10
so. m. . . . . . . . . . . . . . . ..: . . . . . . _-. . . . . . . . . 1:BTP. t o E . P .................... ......... Flash point (Clevelaiid open cup). . . . . . . . . . . . Fir? point (Cleveland open cup), ... . . . . . . . . OVER Per cent 10
IO
Benzene equivalent is the percentage of henzene in a blend of straight run Pennsylvania gasoline.
20 30 40 50 55.5 63.8
TEMPERATURB 0 P.
c.
233 274 313 341 367 3S1 383 385 303 408
Over: -~ Total., . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . At 210° C.(410° F . ) . .. . . . . . . . . . . . . . . . . . . . At 22.5' C . (437O F , ) ,. . . . . . . . . . . . . . . . . . . . . A t 300' C. ( 5 i 2 ' F.). ..................... Water. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coke, by weight.. . . . . . . . . . . . . . . . . . . . . . . . . . .
452 526 593 645 602 717 722 725 740 767
Table VII--100 cc. Engler D i s t i l l a t i o n of Tar-Acid-Free Motor Fuel Grade.. .......................... 225' C. (437' F.)-E. P. Sp. gr.. .......................... 0.7640 (A. P. I . , 5 2 . 3 " ) I . I3. P. to E. P.. . . . . . . . . . . . . . . . . . . 64-226' C. (130-439' F.)
Per cenl 94 4.5
8.5 27.0 Trace ti.5
The crude tar contained 0.55 per cent of snlfur. This quantity of sulfur in a coal-tar stock does not cause trouljlesome corrosion of the eqnipment, because ammonia is formed by the thermal decomposition of the nitrogen compounds,
TEMPERATURE
OVER Per cent
c.
F.
10
88
100
20 30 40 50 60 70
107 122
227 2.52
80
90 95
E. P. Over.. ................................. nottoms..
.............................. Loss.. .................................
Per cenl 98 1
1
INDUSTRIAL AND ENGINEERING CHEMISTRY
1086
The distillation characteristics of the tar-acid-free motor fuel produced above are shown in Table VII. The tar-acid-free pressure-disti1lat)e bottoms produced when making 225' C. (437' F.) end-point motor fuel had the distJillation properties shown in Table VIII. Engler Distillation of Tar-Acid-Free PressureDistillate B o t t o m s Sp. gr.. ........................... 0 . 8 8 9 4 (A. P. J., 27.6') 1. B. P. to I?. P.. . . . . . . . . . . . . . . . . . . . 233-381' C. (452-718' F.)
T a b l e VIII--100
CC.
TEMPERATURE
OVER
c.
PBr renl 10 20 30 40
244 249 254 261 269 278 292 312 343 381 Above 381
50 60 70
so
90 95 E. P.
F. 472 480 440 50'2 516 532 5.58 594 650 718 Above 718
. . . . . . . . . . . . . . . . . . . . . . . 98
......................
2
Table TX summarizes the yields of products obtainable from the cannel-coal tar. of Yields of Products Grade ................................ 225' C. (437OP.) E. P. Table IX-Summary
Tar acids (alkali-soluble), . . . . . . . . . . . . . . . . . . . . . . . . . . . Tar-acid-free motor fuel 2Tij0 C. Tar-acid-free pressure-distillate b Coke and gas. including loss.. . . . Redisri!laLion loss.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Total..
..
....................................
Per cent 10.8 1.3
100.0
A further reduction in the yield of finished motor fuel of 3 per cent would he brought about during the refining by the removal of the tar bases. The final yield is 39.1 per cent. Recycling of the 22.0 per cent of tar-acid-free prcssure-distillate huttoms should increase the yield of finished motor fuel to approximately 49 per cent. The coke and gas yield, including the loss, would be increased to 35.8 per cent. T h w e were 106 pounds of coke and 577 cubic feet of gas produced per barrel of oil cracked. Table X summarizes the cracking data. Kind of oil..
..
le X-Summary
. -
of Cracking D a t a
. . . . . . . . . . . . . . . . . Kentucky cannel-coal tar . . . . . . . . . . . . . . . . 0.9036 (8. P. I., 25.1')
Raw oil, per cent.. . . Sp. gr... . . . . . . Tar acid extracte
. . . . . . . . . . . . . . 66.0
...................
essure distillate:
Loss:
0 , 7 9 8 1 (A. P. l . , 4 5 . 8 " )
. . . . . . . . . . . . . . . . . . . 10.8
.........................
Residuum. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Coke, pounds per barrel.. . . . . . . . . . . . . . . . . . . . . Gas. cubir Feet per b:rrel.. . . . . . . . . . . . . . . . . . . . Coke and gas, including loss (per cent equivalent to volume of unrecovered oil). . . . . . . . . . . . . . . Tar-arid.free motor fuel 225' C. (437' F.)E. P.: Pres sure distillate, per cent.. . . . . . . . . . . . . . . . Raw oil, per cent. . . . . . . . . . . . . . . . . . . . . . . . Sp. gr.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I. H. P. to I?, P.. .......................... Pressure distillate c u t . . .................... Tar-acid-free pressure-distillate bottoms: Pressure distillate, per cent.. . . . . . . . . . . . . . . . Raw oil, per cent.. . . . . . . . . . . . . . . . . . . . . . . . . SD.pr.. ..................................
(3) Wash with 10 pounds of 66" BC. sulfuric acid per harrel of distillate diluted with water to equal a 10' B6. solution of acid (10 per cent by weight) to remove the tar bases, settle, and draw the sludge. (4) .Agitate with 1 pound of 66" Be. sulfuric acid per barrel of distillate to dry the oil, settle, and draw the sludge. Do not wash! (5) Agitate with 7 pounds more of 66' Be. wlfuric acid per barrel as the main acid treatment, settle, and draw the sludge, (6) Wash well with water (preferably by showering). (7) Neutralize with about 1 per cent by volume of 16' Be. sodium plumbite solution, settle, and draw the sludge. (8) Distil a t a maximum still temperature of 250-275' F. (120-135' C.) with all steam in the presence of 1 pound of fuller's earth per barrel of distillate.
The above treatment produced a water-white, doctorsweet, non-corrosive (copper strip), and light-stable motor fuel free from t a r bases and tar acids. The sulfur content was 0.13 pcr cent. The refining loss in addition to the removnl of tar acids and t a r bases was 2.5 per cent. This loss is of the same order as the loss of similar treatment of cracked distillate from petroleum products.
Per cent Over.. . . . . . . . Bottoms. . . . . .
Vol. 21, No, 11
0 . 7 9 7 6 (A. P. I., 4 5 . 9 9 None 106 577
23.2 63.8 42-1 0. ,699 (A P. I. 5 2 . 3 9 54-226' C: (130L43g0F.) 227' C. (440' F.)
34.2 2'2.6 0 , 8 8 9 4 (A. P. I . , 27.6')
-
Pressure dislillate, per c e n t . . . . . . . . . . . . . . . . . 2 . 0 1.3 Raw oil, per cent.. ........................
T r e a t m e n t of Pressure Distillate
T h e pressure distillate, which contained 0.32 per cent of Sulfur, 14 per Cent of tar acids, and 6 per cent of tar bases, was refined by the following procedure: (1) Wash with about 5 per cent by volume of 30' Be. caustic soda to remove all the tar acids, settle. and draw the sludge. (2) Wash well with water (preferably by showering).
Antiknock Properties of Gasoline
Refined gasolines of varying end points from which the tar acids and tar bases had been extracted were tested for antiknock properties. The motor tests were made upon a singlecylinder Delco engine equipped with a water-cooled head and bouncing pin with indicator, following the general method described by Faragher and Hubner ( 5 ) . Four samples were tested showing the following results: END POINT
C.
F.
160 177 199 225
320 350 390 437
BENZENE I N PENNSYLVANIA STRAIGHT-RUN GASOLINE Per cent 43 38 30 10
From these results the curve was drawn which by extrapolation showed the percentage of benzene in standard blends t o which gasolines with end points from 93" C. (200' F.) to 223' C. (437' F.) are equivalent. The standard blends were made from benzene and a selected straight-run gasoline of definite characteristics-e. g., a Pennsylvania straight-run gasoline. The pressure-distillate bottoms made from t h e four endpoint gasolines were analyzed to determine their suitability for domestic furnace oil and, with the exception of the bottoms from the navy end-point gasoline, were found t o meet the specifications recently approved by the American Oil Burner Association for No. 1 and No. 2 furnace oils. Special cuts within this boiling range may also be suitable for varnishmaker's and painter's naphtha, painter's solveht, turpentine substitute, and other specialty products. Literature Cited (1) Berry and Dunstan, J. SOL.Ckem.I n d . , 37, 175A (1918). (2) Bur. Mines, Bull. 22 (1912). (3) Craig, J. SOC.Chem. I n d . . 31, 175A (1918). (4) Day, Bur. Mines, Minernl Resources of U. S., p. 257 (1887). (5) Faragher and Hubner, J. SOC.Automotive Eng., 20, 405 (1927). (6) Fettke, Trans. A m . I n s l . M i n i m M e l . Eng., No. 1233 (1923). (7) Gentry, "Technology of Low-Temperature Carbonization," p. 253 (1928). (8) Tropsch, Ckem. Rev., 6, 81 (1929).
Poisonous Acid Found in Arrow Grass--Hydrocyanic acid, a poison that has caused the death of many cattle in western Nebraska, Utah, Wyoming, and Nevada, exists in small quantities in arrow grass, an herb found in salty or alkaline spots near streams and lakes, according to Techniral Bulletin 113-Tof the Department of Agriculture. Arrow grass is a perennial herb, growing to a height of from 6 inches t o 21/2 feet.
'
