Energy & Fuels 1990,4, 201-206 in the reagents tested is the type of ring heteroatom bonded to the phosphorus atom. In order to investigate whether a different ring size has a salutory effect on the observed chemical shift ranges, reagent 7 was evaluated. Reagent 7 is a 1,3-dithiaphosphorinane in which the phosphorus atom is part of a conformationally mobile six-membered ring. The observed 31Pchemical shift ranges for phenols and alcohols completely overlap, and moreover, they are not as large as was observed for reagent 2, for example. Furthermore, carboxylic acids derivatized with reagent 7 provide unstable products which decompose rapidly to a complex mixture of products. The increased
20 1
ring size in 7 does not, therefore, appear to enhance the effectiveness of this reagent.
Acknowledgment. Ames Laboratory is operated for the U S . Department of Energy by Iowa State University under Contract No. W-7405-ENG-82. This work was supported, in part, by the Assistant Secretary for Fossil Energy through the Pittsburgh Energy Technology Center. Partial support through DOE Grant No. DE-FG2288PC88923 is also acknowledged. Registry No. 1, 14812-59-0; 2, 4669-51-6; 5, 30148-56-2; 6, 6069-36-9; 7, 28896-84-6.
Tritium as a Tracer in Coal Liquefaction. 3. Reactions of Morwell Brown Coal with Tritiated Hydrogen Molecules Toshiaki Kabe,* Kenichi Kimura, Hideo Kameyama, Atsushi Ishihara, and Kyoko Yamamoto Department of Chemical Engineering, Tokyo University of Agriculture and Technology, Nakamachi, Koganei-shi, Tokyo 184, Japan Received September 22, 1989. Revised Manuscript Received January 29, 1990
The liquefaction of Morwell brown coal was carried out with tritium-labeled gaseous hydrogen. The effects of Ni-Mo-Alz03 catalyst, reaction time, and temperature on the hydrogen transfer were studied. The relationships between liquefaction conversions and hydrogen-tritium transfers were investigated. Morwell brown coal was easily liquefied at 350 "C, and the conversion reached ca. 100% at 400 "C even without catalyst. The liquefaction proceeded by the hydrogen donation from solvent to coal. Ni-Mo-Alz03 was not so useful for the coal conversion but was effective for the cracking of the coal liquids. Furthermore, the catalyst promoted hydrogen exchange between the gas phase and the coal. At the initial stage of the reaction, tritium concentrations in heavy components were higher than those in light components, in both the presence and absence of the catalyst, which was reversed a t the final stage.
Introduction In order to develop a practical process for coal liquefaction, it is important to elucidate the mechanisms of coal liquefaction. The estimation of the mobility of hydrogen in coal gives a key to solve them. Since the pioneering study of deuterium under magnetic resonance spectroscopy (2H NMR) by Schweighardt et al.,I a number of attempts have been made to elucidate the mechanisms of coal liquefaction by using deuterium tracer and NMR or MS methods.z-12 However, because of the lack of quantitative
data from 2H NMR, there are very few examples that enable the quantitative analysis of hydrogen transfer in coal liquefaction. We reported that the tritium and 14C tracer techniques were effective tracing the reaction pathways of hydrogen atoms in Taiheiyo, Wandoan, and Datong coal liquefaction and gave quantitative information related to hydrogen transfer in the subbituminous and bituminous coal^.'^-'^ (8) Wilson, M. A,; Collin, P. Process. Technol. 1982,5, 281.
4.; Barron, P. F.; Vassalo, A. M. Fuel
(9) Wilson, M. A,; Vassalo, A. M.; Collin, P. J. Fuel Process. Technol.
(1)Schweighardt, F. K.; Bockrath, B. C.; Friedel, R. A.; Retkofsky, H. L.Anal. Chem. 1976,48, 1254. (2)Heredy, L.A.; Scowronski, R. P.; Ratto, J. J.; Golberg, I. B. Prepr. Pap.-Am. Chem. Soc., Diu. Fuel Chem. 1981,26, 114. (3) Ratto, J. J.; Heredy, L. A.; Skowronski, R. P. Prepr. Pap.-Am. Chem. SOC.,Diu. Fuel Chem. 1979,24, 154. (4)Franz, J. A. Fuel 1979, 58, 405. (5) Franz, J. A.; Camaioni, D. M. Prepr. Pap.-Am. Chem. Soc., Diu. Fuel Chem. 1981,26, 106. (6)Cronauer, D.C.; Mcneil, R. I.; Young, D. C.;Ruberto, R. G. Fuel 1982, 61, 610. (7) Brower, K. P. J. Org. Chem. 1982, 47, 1889.
0887-0624/90/2504-0201$02.50/0
1984, 8,213.
(10) Skowronski.R. P.:Ratto. J. J.: Goldbera. - I. B.; Heredv, L. A. &el
1984, 63, 440.
(11) Maekawa, Y.; Nakata, Y.; Ueda, S.; Yoshida, T.; Yoshida, Y. In Coal Liauefaction Fundamentals: Whitehurst. D. D.. Ed.: ACS SWIIDO-
sium Shies 139;American Chemical Society: Washington, DC, f986; p
315. (12)King, H.H.;Stock, L. M. Fuel 1982, 61, 129. (13) Kabe, T.;Nitoh, 0.; Kim, S. J. J p n . Pet. Inst. 1983, 26, 424. (14)Kabe, T.;Nitoh, 0.;Kawakami, A.; Okuyama, S.; Yamamoto, K. Fuel 1989,68,178. (15) Kabe, T.; Nitoh, 0.; Funatsu, E.; Yamamoto, K. Fuel Process. Technol. 1986,14, 91.
0 1990 American Chemical Society
Kabe et al.
202 Energy & Fuels, Vol. 4 , No. 2, 1990 Table I. Distribution of Products and Tritium in a Noncatalytic System" mass tritium Droducts e % dDm % coal 6.15 82 294 9.39 40.15 residue 3.24 43 542 6.01 25.69 BIS-THFS 2.15 28 890 4.59 19.62 HIS-BS 0.68 6.63 9 157 1.55 HS 0.76 10 178 5.43 1.27 light oil 0.31 4 193 0.51 0.12 naphtha 0.25b 1.07 1090 40OC 81.13 gas 0.72 9 722 0.90 0.21 H20 95.14 total 23.39 94.78d 1278 676
Table 11. Distribution of Products and Tritium in a Catalytic System" mass tritium products R % dpm % coal 22.62 77 120 7.23 4.94 residue 10.01 27.29 106744 5.96 BIS-THFS 7.57 27.85 80 757 6.08 HIS-BS 40 045 3.75 10.78 2.35 HS 2.74 6.50 29 249 1.42 light oil 1.79 1.49 19 143 0.33 naphtha 2.34 395 oooc 37.03 0.51b gas 15 429 1.14 1.45 0.25 H20 71.57 763 487 21.84 89.20d total
solvent tetralin naphthalene total
61.55 7.91 69.46
88.61 11.39 91.50e
60871 4455 65326
solvent tetralin naphthalene total
68.21 4.32 72.53
94.05 5.95 94.85e
270291 33056 303347
25.58 2.86 28.44
total
92.85
92.30d
1344 002
total
94.37
93.48d
1066 830
96.28e
4.53 0.33 4.86 100.96e
"Coal, 25.2336 g; tetralin, 75.9137 g; catalyst, 0 g; initial hydrogen pressure 60.0 kg/cm2; temperature 350 "C; reaction time 120 min; initial radioactivity in gas phase 1331160 dpm; initial amount of hydrogen in gas phase 1.25 g; final pressure in gas phase 60.0 kg/cm2. Carbon dioxide, carbon monoxide, and hydrocarbons are involved. Weight of molecular hydrogen is not included. Regarded as radioactivity in gaseous hydrogen. dRecovery (daf basis). e Recovery.
We studied the liquefaction of brown coal using a tritium tracer technique. Recently, although much attention has been focused on the liquefaction of Victorian brown ~ 0 8 1there , ~ have ~ ~ been ~ few examples in which the hydrogen mobility in brown coal, especially the quantitative aspect of the hydrogen transfer, was investigated. In this paper, the liquefaction behavior of Morwell brown coal under tritium-labeled hydrogen atmosphere was investigated to obtain information on hydrogen mobility in the low-rank coals.
Experimental Section Materials. Morwell brown coal (analysis: C, 70.6; H, 4.5; N, 0.6; S, 0.3; 0,24.0 wt %, daf; ash, 2.2 w t %, dry basis) was ground to
