Hydrogenation of High-Volatile Bituminous Coals Proximate Analysis and Characterization of Products L. L. HIRST, H. H. STORCH, C. H. FISHER, AND G. C. SPRUNK Central Experiment Station, U. S. Bureau of Mines, Pittsburgh, Penna.
ESPITE the fact that tent of the washed coal is due Results of coal hydrogenation assay work the major portion of the largely to minute particles (0.23 i n the liquid phase are presented for three to 2 microns in diameter) of United States coal rebituminous coals of high-volatile A, B, and serves comprises the subbitumimineral matter, probably seriC rank. These coals are Mary Lee bed of citic mica, scattered uniformly n o u s c o a l s a n d l i g n i t e s of Alabama, No. 6 bed of Illinois, and McKay Wyoming, Montana, Colorado, throughout the coal. North Dakota, and other Descriptions of the geology bed of Washington. Analytical data are western states, our first coaland petrography of the Illinois given on the products of hydrogenation of No. 6 bed are available (3, 8, hydrogenation plants (designed these three coals and of Pittsburgh seam 11). The 2-ton sample of coal to produce bulk organic chemicoal. I t is shown that organic raw maused for the hydrogenation assay cals rather than gasoline) probterials of industrial importance may be was taken on December 17,1937, ably will be situated in the from the face of No. 6 coal bed Pittsburgh or Chicago industrial produced from coal by hydrogenation. in room 2, off third N off West &Teas. Because of this and also S o r t h in Orient KO. 2 mine a t because the standard (PittsWest Frankfort, Franklin County, Ill. The section of the burgh bed) coal adopted by this laboratory for hydrogenation bed a t the point of sampling closely resembled the section purposes was a high-volatile A bituminous coal ( I S ) it seemed from Orient KO.1 mine described by the Bureau of Mines desirable to assay a few additional high-volatile bituminous coals. Those chosen for this work were: ( a ) High (nearly ( 8 ) . This section showed that No. 6 bed coal is a predominantly bright coal of uniform petrography. The petromedium) volatile A bituminous, Mary Lee bed, Alabama; graphic and chemical analyses in Table I indicate that this (b) high-volatile B bituminous, Illinois S o . 6 bed; ( c ) highcoal should liquefy as readily as the Bruceton coal. volatile C bituminous, AIcKay bed, Washington. The geology of Washington coals was described by CampThe Mary Lee coal bed lies in the Warrior field west and bell (4). The hydrogenation assay sample was taken from north of central Alabama. The sample of Mary Lee coal chute 13, 10 feet above the second level gangway, 600 feet used for the hydrogenation assay was from the product of southwest of slope bottom, in the Strain-Upper Diamond the washing plant of the Sayreton mine of the Republic Steel mine of the McKay bed, King County. The section of the Company, Thomas Station, Birmingham, Ala. The sample bed a t this point shows 4 feet 1 inch of bright coal and 8 inches was taken as the cars containing washed co'al were being unof bone and bony coal. The latter was excluded from the loaded a t the by-product coke plant. Sampling covered a sample. The coal for the hydrogenation assay sample was 7-hour period, during the unloading of eight railroad cars; mined by hand. the sample should therefore be representative of the full Strain-Upper Diamond mine coal is a bright, high-volatile thickness of the Mary Lee bed at Sayreton. At regularly C, noncaking coal. The petrographic and chemical analyses timed intervals small increments of 'the washed coal were are given in Table I. The absence of fusain and the low contaken off the conveyor belt which carries the coal up t o the tent of opaque attrital matter indicate that this coal should storage bin over the coke ovens. be exceptionally well suited for hydrogenation. Coals of this The results of a petrographic examination of a column type are rarely found in the Paleozoic coals of the mid-consample of the Mary Lee bed have already been published tinent and eastern United States fields. In these older coals ( 7 ) . It is mainly a bright coal-that is, a finely banded coal it is unusual t o find a seam with less than 5 per cent combined whose chief constituents are anthraxylon and attritus; the opaque attritus and fusain. latter is composed predominantly of translucent humic matter. The recognizable plant remains in this coal are derived from nonresinous tissues. Petrographic and chemical Operating Difficulties analyses are given in Table I. The plant equipment and assay procedure have been deBecause of its high carbon content (87 per cent on a moisscribed ( I S ) . For the work done with the Bruceton (Pittsture- and ash-free basis compared with 84 per cent for Pittsburgh bed) coal and in some of the runs with the Illinois Xo. burgh seam coal) and its relatively high ash and fusain con6 coal a heat exchanger for preheating hydrogen was used. tents, it was expected that the Mary Lee bed coal would not This exchanger was inserted into the top section of the highhydrogenate as readily as the Pittsburgh bed coal from the pressure converter (Figure 1) and has been described ( 1 3 ) . Experimental ,Mine a t Bruceton, Penna. The high ash con-
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JUNE, 1940 TABLEI.
INDUSTRIAL AND ENGINEERING CHEMISTRY PETROGR.4PHIC AND
Constituents, Moisture Volatile matter Fixed carbon Ash
CHEIfICAL AXALYSES
M a r y Lee Bed No. 6 Bed .&Received Basis 4.2 7.8 27.0 33.7 52.0 59.0 9.8 6.5 Moisture-Free Basis
3 l c K a y Bed 9.6 40.1 46.6 3.7
Hydrogen Carbon Nitrogen Oxygen Sulfur Ash Hydrogen Carbon Piitrogen Oxygen Sulfur Anthraxylon Translucent attritus Opaque attritus Fusain
Moisture- and Ash-Free Basis 5.4 5.3 S6.9 SO. 6 1.8 1.9 5.0 10.0 0.9 2.2 Petrographio Data 61 24 TO 2;
7
1
5
5.9
i s .6
2.2 12.5 0.8
is the presence of relatively large amounts of chlorine in Illinois KO.6 coal (0.39 per cent of the moisture- and ash-free coal compared with 0.06 for Bruceton and practically zero for the Mary Lee and Washington coals). Volatile chlorine compounds are active catalysts for the primary liquefaction of coal. There is a possibility of deposition of ammonium chloride as a nucleub fur condensation of spray in the vapor exit tube. The high-volatile C coal from the 1IcKay bed in King County, Wash., hydrogenated easily with no operating difficulties. This coal is in many respects the most desirable raw material for hydrogenation thus far used in our plant assay work. I t s desirable qualities are low ash, almost no fusain, very little opaque attrltua, low viscosity of heavy-oil product, and lorn gas loss.
65 34 1 0
F - 1 9 ’ ’ diarn.----( ,Therrndcouple well
lH2
inlet^$
I t was useful, particularly in those experiments where either the gas circulation or paste pumping rate was high. As a reflux device i t had some utility, but because the reflux temperature was fixed for any particular coil by the gas circulation rate, it lacked flexibility. It also had the disadvantage that it partly clogged at times and made high compressor delivery pressure necessary or forced use of the auxiliary hydrogen inlet in the bottom closure. For the runs with the McKay and Mary Lee bed coals, refluxing was obtained by pumping water a t suitable rates through a coil similar to the heat exchanger but made of 1/4-inch 0. d. X ‘/s-inch i. d . stainless steel. The inlet and outlet ends of this coil were brought through the converter head. I n starting the assay of each of the three bituminous coals, coal tar obtained by carbonization in Knowles ovens of Illinois No. 6 coal from Orient S o . 2 mine v a s used as pasting oil. The coals were ground in a ball mill until about 50 per cent passed through a 200-mesh sieve and not more than about 0.5 per cent remained on an 80-mesh siere. This pun-dered coal was then dried until the moisture was reduced to less than 1 per cent in all cases. For all coals the catalyst mas 0.5 per cent stannous sulfide and 0.5 per cent molybdenum trioxide. Considerable difficulty was experienced in pumping paste made from the Mary Lee coal. Although this paste is very fluid when first prepared, circulation during pumping causes i t to form a stiff suspension. This behavior was alleviated somewhat by careful sizing of the coal (that is, avoiding the finer sizes below 200-mesh as much as possible) ; nevertheless, this coal paste is definitely difficult to pump. These pumping difficulties consist mainly in frequent clogging of the check valves on the paste pump by a “filtration” effect whereby the pasting oil is removed by the pump, leaving a dry, hard layer of coal dust on the valve seat. The 10 per cent ash in this coal which cannot be removed by ordinary washing occurs as very small particles of mineral matter uniformly distributed throughout the body of the coal. It is therefore probable that the interfacial tension between this coal and its pasting fluid is markedly different from that with all other coals tested. This may explain the ease with which the coal particles are separated from the pasting oil during the pumping operation. There were no paste-pumping difficulties with either Illinois No. 6 or the Washington coal. With Illinois No. 6 coal it wa5 essential to operate with a fairly high reflux temperature in order to avoid clogging of the vapor outlet passage through the top closure of the converter (Figure 1). A possible explanation of the clogging
865
‘ e H2, bverhead oil -No. 4 therm couple in well
- Heatreflux exchanger or coil -No. 3 -Stand pipe for discharging heavy oil slurry
-No. 2
-Heat insulation p3-
-NO. I
.Heating element and supporting refractory p4-
-NO. 0 -Air space
converter -7
3upportiing table
FIGURE 1. SECTIOX THROUGH COALHYDROGEXATION CoxVERTER .---,C a d y , G. H., Illinois M i n i n g Investigations. Bull. 26 (1926). C a m p b e l l , >I. R . , U. S.Geol. S u r v e y , ProfessionuZ P a p e r 100-A (1922). D e p t . Sci. I n d . R e s e a r c h ( B r i t . ) , F u e l R e s e a r c h B o a r d , R e p t . for T e a r E n d e d M a r c h 31, 1930, pp. 105-6. F e i n , M. L., E i s n e r , A , , Cooper, H . M., a n d Fisher, C. H . , ISD.ESL. CHEM.,.Inal. E d . , 11, 432-8 (1939). Fieldner, A. C., a n d others, U. S. B u r . Mines, Tech. Paper 519 (1932). Fieldner, A. C., a n d others, Ibid., 524 (1932). Fisher, C . H., a n d E i s n e r , d.,IXD. ENC.C H m r . , Anal. E d . , 9, 213-18 (1937). Ibid., 9, 366-70 (1937). Fisher, D. J., Illinois Geol. S u r v e y , Rept. Investioations 5 (1928).
JUNE, 1940
INDUSTRIAL AND ENGINEERING CHEMISTRY
(12) Heyn, M., and Dunkel, M., Brennstof-Chem., 7, 20-5, 81-7, 245-50 (1926). EXQ.C H E M .31, , 869-77 (1939). (13) Hirst, L. L., and others, IND. (14) Horton, L., Williams. F. -4., and King, J. G., Dept. Sci. Ind.
Research (Brit.), Fuel Research, Tech. Paper 42,’London,
H. M. Stationery Office, 1935. (15) I. G. Farbenindustrie, A,-G., British Patent 435,254 (Jan. 29, 1935). (16) Ibid., 470,338 (March 4 , 1936). (17) Ibid., 497,089 (Dec. 4 , 1937). (18) I. G. Farbetlindustrie, A.-G., German Patent 655,103 (Jan. 8, (1938). (19) Ibid., 659,878 (May 12, 1938). ENG.C H E U . , Anal. Ed., (20) Kester, E. B., and Pohle, W. D., IND. 3 , 294-7 (1931). (21) McArdle, E. H., Moon, J. C., Terrell, H . D., and Haines, E. C . , Ibid., 11, 248-50 (1939). (22) Natl. Bur. Standards, Circ. C410 (1936).
87 1
(23) Norris, J. F., and Joubert, J. M., J . Am. Chem. SOC.,49, 873-86 (1927). (24) Pertierra, J. M., Anales SOC. espaR. fis. quim., 28, 792-806 (1930). (25) Ibid., 30, 792-3 (1932). ( 2 6 ) Scholl, R., and Meyer, K., Ber., 71, 407 (1938). (27) Tongberg, C. O., Quiggle, D., and Fenske, M. R., I N D .ESG. C H E M . 26, , 1213-17 (1934). (28) Tropsch, H., and Ter-Nedden, W., Brannstof-Chem., 6 , 113-5 (1925). (29) Uchida, S., J . Fuel SOC.Japan, 14, 3 8 4 4 (1935). (30) ~ a r r e nT. , E., and Bowles. K. W., Can. Dept. of Mines, -1Iines Branch R e p t . 737-3, 11-31 (1933). PRESENTED before the Division of Gas and Fuel Chemistry a t the 98th Meeting of the American Chemical Society, Boston, Mass. Published by permission of the Director, U. S. Bureau of Mines. ( N o t subject t o copgright.)
Surface Tension of a Solvent-Diluent Mixture Samples of two mixtures w-ere evaporated to different stages. These mixtures were such that nitrocellulose solutions of them were comparable as to viscosity and dilution ratio. Surface tension data on the series of saniples of both solvent-diluent mixtures brought out the follow7ing relation: The solvent mixture containing toluene alone as the diluent had a greater surface tension than the solvent-diluent mixture w-hich contained Troluoil. The relation apparently persisted even when solutions were made with nitrocellulose alone or combined with ester gum. None1 aporated solutions were applied to metal, glass, and wood, by dipping or flow coating. The solutions in which the diluent was toluene alone soon showed an unusual film-forming characteristic. The wet film began to show a “pullingaway” effect. The wet film began to shrink from the edges of the pour in the case of plane surfaces. The wet film began to shrink from the sharp edges of an object that had been dipped.
J. I
