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Energy & Fuels 1991,5,724-729
Coal Maceral Chemistry. 1. Liquefaction Behavior J. T. Joseph,* R. B. Fisher, and C. A. Masin Amoco Oil Research and Development Department, Amoco Research Center, Naperville, Illinois 60566
G. R. Dyrkacz, C. A. Bloomquist, and R. E. Winans Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60539 Received April 22, 1991. Revised Manuscript Received June 28, 1991 Three groups of macerals, namely liptinite, vitrinite, and inertinite, were separated from a West Virginia high-volatile bituminous coal (APCS 7 from the Argonne Premium Coal Sample Bank) by continuous flow density gradient technique and their pyrolysis and liquefaction behavior studied. The pyrolysis and liquefaction yields decreased in the order: liptinite > vitrinite ? inertinite. There was no discernible interaction among the macerals during pyrolysis or liquefaction. The least reactive inertinites, which makes -15% of the above coal, is projected to have little influence on conversion and product distribution of the whole coal. Therefore, inertinite removal prior to liquefaction can potentially improve process efficiency. Addition of dispersed iron catalyst did not alter the liquefaction of the liptinite, while vitrinite and inertinite gave enhanced oil yields.
Introduction The major objectives of this study are (1)to understand the liquefaction behavior of individual coal macerals, (2) to determine if there are interactions among the different maceral groups during pyrolysis and liquefaction, and (3) to ascertain if selective removal of relatively unreactive macerals would affect overall coal liquefaction. Macerals are microscopically distinct components of the organic matter of coal, they are different in their chemical and physical properties such as hydrogen content, aromaticity, heteroatom content, reflectance, and density. Reactivities of the macerals during liquefaction or pyrolysis are also different. Detailed descriptions of the various types of coal macerals can be found in publications by Van Krevelen,' Stach,2 and Ting.3 Since coal is a heterogeneous mixture of macerals, characterization and liquefaction studies of whole coals give only information averaged over the entire range of the macerals. During coal liquefaction, all the macerals react in the presence of an excess hydrogen donor solvent. Therefore, liquefaction products and the kinetics of liquefaction of individual macerals cannot be distinguished. In order to better understand coal structure and ita true reaction mechanisms, each maceral has to be studied independently under conditions mild enough to distinguish their reactivities. This requires separation and characterization of macerals in relatively large quantities. One approach to maceral separation is based on the differences in their densities.'& Density-based separation of all of the several individual macerals is difficult because of the small differences in their densities and the overlap of their density distributions. Therefore, for practical purposes, macerals of similar properties are often grouped in order of increasing density into three types: liptinites, vitn'nites, and inertinitea2 These maceral groups can be separated in very high purity by density gradient centrifugation technique^.^ However, density gradient methods are not conducive to providing large amounts of low abundance macerals within a reasonable time. In these cases, either sink-float centrifugation or continuous flow centrifugation
* Address all correspondence to this author at Amoco Research Center, P.O. Box 3011 H-4, Naperville, IL 60566-7011.
techniques are more appropriate.6
Experimental Section Coal. The coal used for the current study was a high-volatile West Virginia bituminous coal (Lewiston-Stockton seam) from
the Argonne Premium Coal Sample Bank (APCS 7).8 Maceral Separation. Prior to separation,the coal was first ground to vitrinite > inertinite. The least reactive inertinite
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has been projected to have little influence on conversion and product distribution of the whole APCS 7 coal. The vitrinite and inertinite conversion during liquefaction can be enhanced by the addition of iron as a & p e d catalysk the effect of added iron depends on the aromaticity of the maceral. The conversion of the inertinite during liquefaction is significantly increased by the addition of -1 wt % iron, even though the inertinite already contains 0.9 wt 5% iron as pyrite.
Acknowledgment. This paper is the first of a aeries from the Amoco-Argonne Collaborative Coal Chemistry Research Program,started in 1989. We acknowledge the continuing support of both Amoco Oil Co. and Argonne National Laboratory managements, especially Mr. Keith W. McHenry, Mr. Allen A. Kozinski, and Mr. Robert E. Lumpkin of Amoco, and Dr. Alan Schriescheim and Dr. Leon M. Stock of Argonne National Laboratory. The work at Argonne National Laboratory was supported by US. Department of Energy, Office of Basic Energy Sciences, Chemical Sciences Division, under Contract No. W-31109-ENG-38. Registry No. Fe, 7439-89-6; Fe(C0I5, 13463-40-6.
Absorption of CO, H2, and CHI in Toluene and Copper(1) Tetrachloroaluminate-Toluene Solutions at Elevated Pressures Jurgen Koschel,*J Andreas Pfennig: Martin Henschke, and Hugo Hartmann Lehrstuhl N fur Verfahrenstechnik,R WTH Aachen, Wullnerstrasse 5, 0-5100 Aachen, Germany Received December 1, 1990. Revised Manuscript Received June 10, 1991
Solubilities of the coal-gasification products CO, H2,and CHI in pure toluene have been measured at temperatures between 249 and 343 K and pressures up to 7 MPa. Phase equilibria of CO and copper(1) tetrachloroaluminats-toluene solutions are presented between 254 and 333 K and pressures up to 9.5 MPa. In this absorbent, reversible chemical reactions occur resulting in a formation of several bimetallic salt complexes having a high bonding capacity for CO. Solubility measurements with H2 and CHI in this agent show that these gases do not undergo any chemical reaction.
Introduction To separate the valuable components CO, H2, and CHI resulting from coal gasification a washing process has been proposed by Esser.' His process is an extended version of the Cosorb process developed by Haase and Walker,2 where CO is removed from suitable gas mixtures by chemically binding it to a bimetallic salt, preferably consisting of copper(1) tetrachloroaluminate (CuAlC14)and toluene (C,H8).s*4 In the process proposed by Eeeer, the prepurified syngas passes a high-pressure absorber in which CO is absorbed mainly through complex formation in the liquid phase whereas CHI is physically dissolved because of its high 'Present address: BASF AG, D-6700 Ludwigshafen, Germany. t Present address: Institut fOr Chemische Technologie, TH Darmstadt, Petersenstram 20, D-6100 Darmstadt, Germany.
solubility. H2 leaves the absorber overhead as an 8-811tially inert component. In a first regeneration step CHI (1) Ewer, D. Messun en von Abeorptione- und Chemieorptiomgleichgewichtenzwiechen lyntheaegaaund K o h l e n m e n mit einer Lewieeaure bei hohen Drticken. Diseertation, R W T H Aachen, 1984. (2) Hw, D.J.; Walker, D. G.The COSORB h C 0 8 8 . Chem. Eng. h o g . 1974, 70, 5. (3) Turnbo, R. G. Procew for the Preparation of Bimetallic Salt Complexes. United Statas Patent 3,867,869; 1974. (4) Sudduth, J. R;Keyworth, D. A procervl for the purification of Gm Streams. United Statas Patent 3,WO,91@1976. (5) Koechel, J. Zum Phaaengleichgewicht zwiden Synthaagan und Kupferaluminiumtetrachlorid-Toluol-Ltieuenunter dem baaonderen Aspekt der Synthesegaezerlegmg. Diuaertation, RWTH Aachen; Fort schritt Berichte VDI,Reihe 3, No. 203. Dtbwldorf, 1990. (6) Vargaftik, N. B. Handbook ofPhy8iCal Propertie8 of Liq& and Gosee, 2nd ed.; HemLphere P u b l i i Corp.: Dc,lQ7L (7) N. N. Determination of Carbon%onoxide Solub ty in the Cup rous Aluminum Tetrachloride-Toluene Absorbent. Zhejtang Dame Xuebao 1980,1, 24.
0887-0624191/ 2505-0729$02.50/0 Q 1991 American Chemical Society
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