liquefaction pathways of bituminous subbituminous coals andtheir

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icher in such functionalities. The ether region between 1100-1300 cm-1 also showed significantly intense positive bands which clearly suggests that more of ether type bonds are broken during catalytic liquefaction compared to that of the thermal ms. At the high oxidation level the ether region did not show any noticeable difference in the ether contents of the thermal and catalytic residues. The most significant difference was observed in the coal dried at 100 OC. Pyrolysis-CC-MS Compsred to the raw coal the residues from the thermal solvent-free liquefactions show similar pyrolysis compounds. that is one can identify the same compounds in the raw coal as well as in residues. The differences in the pyrograms appear to be in the relative abundances of the compounds. Table 1 gives the ratios between phenolic and akylbenzene compunds. For these ratios same compounds have been used as for the raw coal mentioned above. These ratios indicate the variations in the chemical composition of the aromatic compounds in the coal network as a consequence of different treatments to coal. After solvent-free thermal liquefaction of the raw coal the phenolic to akylbenzene mi0 decreaw remarhbly compand to that of the unreaced coal. Similar decrease is obseveed for the airdriedcoal at 100 T for2 h and the vacuum-dried coal. For thecoal dried at 100T for20 and 100 hand driedat 150 'C there is no significant change in this ratio. From the catalytic solvent-free liquefaction the phenolic to akylbenzene ratios of the residues are slightly higher than that of the corresponding residue from the thermal run but it is still lower than that of the unreacted coal. It appears that as the oxidative drying proceeds the difference in the phenolic to alkyltenzene ratio between the umackd coal and the liquefaction residue decreases. Eventually at extensive oxidation of coal this ratio becomes Same for the unreacted coal and its liquefaction residue. Figure 4 compares of the pawn of the aliphatics present in the pyrogram of the residues from solvent-free thermal runs. Noticeable differences can be seen in the relative intensities of the aliphatics compared IO that of the corresponding u mted coal. In the residues from the raw and vacuum dried coal there is an appreciable decrease in the intensities of the shoner chain relative to the longer chain aliphatics, which has been noticed before with different coals m. For the air-dried unreacled coal, as mentioned before the pattern of the aliphatics in the pyrogram remains similar with the extent of drying, but for the residues the panern is quite different. By comparing the residues from the airdried coal at different extent of oxidation it appears that as the extent of oxidation increases more and more of longer chain aliphatics are lost during thermal liquefaction (Figure 4). It seems that for the air-dried coal the shoner chain aliphatics are strongly retained upon liquefaction. This phenomena was not observed for the catalytic runs. All the pyrolysis compounds found in the ppgram of the raw coal can also be identified in the pyrogram of the residues from the liquefactions in presence of solvents. Besides, there are several new bands which are known to have come from the the adduction of solvent used during liquefaction (1 1). Some of these compounds are in most abundances. From the liquefaction runs in presence of temlin the peaks due to the solvent are tenalin, dihydronaphtblene, naphlhalene and 1 and 2-methylnaphthalenes. CZnaphthalenes may also be due to temlii but are in a very low abundances. From the runs with 1 -methylnaphthalene IWO solvent adduction bands are observed, naphthalene and I-methylnaphthalene. In our previous work (1 1) we reponed that the adduction of solvents could be either due to the formation of chemical bond between the solvent molecules and coal network or the solvent molecules could be physically enmpped in the micropores. From Figure 5 the adduction of solvent is apparent by the presence of tenalin. dihydronaphthalene. naphthalene and 1 and 2-methylnaphthalene peaks. It is clear that the extent Of adduction of the solvents is remarkably effected by the extent of initial oxidation of the coal. Apparently. as the Oxidation proceeds the relative intensities of the adduced compounds increases. Similar mend was observed in the case when 1-MN was used as solvent. The residues from the catalytic runs also show a similar trends in the adduction of solvents with the drying of coal but during catalytic runs the adduction seems to be lower as compared to the thermal run. Not much difference is observed between the pymgrams qualitatively in Figure 5. All the ppgrams for the raw and dried coal under different conditions have the same compounds but there relative intensities are significantly different. Table 1 gives the phenolic to alkylbenzene ratios. These ratios have increased significantly for residues from the raw coal and for the coal dried in air at 100 'C for 2 h and under vacuum, compared to that of the solvent-free runs. But, for the I-MN runs these ratios seems to be similar to that of the thermal runs. It seems hat during solvent-free runs or in the presence of 1-MN more phenolic type units which pmduce phenolic compounds upon pyrolysis are lost. This phenomena seems to be me for raw, vacuum-dried coal and for the coal dried in air at 100 'C for 2 h. At the higher oxidative drying of coal the change in the ratios of the phenolic to akylbenzene is not significant. 604
CONCLUSIONS The characexizntion of the liquefaction residues reveal lhat the residues from the air-dried coal are more aliphatic and carbonyl rich compared to the vacuumdried coal. The increase in the carbonyls is due to the oxidation of rhc coal upon air-drying. It appears that upon oxidation of coal at I00 'C more shorter chain aliphatics are ruained in the coal nawolk as compared to the vacuum-dried coal. The enhanced conversion of the unoxidized raw coal may be. due to the enhanced loss of carbonyls upon reacting with water. The enhanced loss of carbonyls with wam can make coal Iw refnrtory for liquefaction. ?he Py-GC-MS analysis of the residues suggests that the extent of oxidation can enhance the solvent adduction during liquefaction. ACKNOWLEDGEMENTS This work has been supported by the US. Department of Energy, Pittsburgh Energy Technology Center. We wish to thank h. P. G. Hatcher, Mr. K. Wenzel and Mr. L. Hou for their insnumental support with Py-GC-MS and CPMAS I3C NMR instruments and Dr. M. Sobkowiak for her help with FTIR instrument. REFERENCES I. 2. 3. 4. 5. 6. 7. 8. 9. IO. 11. 12. 13. Cronauer. D.C.. Rubeno, R.G.. Silver, R.S.. Jenkins, R.G., Davis, A,, and Hoover, D.S.; Fuel, 1984, 63, 71-77. Athenon, L.F.; Proc. 1985 Int. Conf. Coal Sci.. p.553. Saini. A.K.. Song, C., and Schokn. H.H.; ACS Fuel Chem. Prepr.. 1993, Preceding Paper, Cronauer, D.C., Rubeno. R.G.. Jenkins, R.G., Davis, A,. Painter, P.C.. Hoover, D.S.; Starsinic. ME., and Schlyer. D.; Fuel, 1983. 62, 1124-1132.. Calemma. V.. Iwanski, P.. Rausa. R.. and Girardi, E.;ACS Fuel Chem. Prepr. 1992,730. Calemma, V.. Rausa, R.. Margarit, R.. and Girardi. E.; Fuel, 1988.67,764. Clemens. A.H.. Matheson. T.W.. and Rogers, D.; Fuel, 1991.70.215. Rhoads. C.A.. Senftle, J.T.. Coleman, M.M., Davis, A,, and Painter. P.C.; Fuel, 1983. 62. 1387. Painter. P.C.. Snyder, R.W.. Pearson. D.E.. and Kwong. J.; Fuel, 1980, 59,283. Chamberlain, E.A.C., Barrass. G.. and Thirlaway. J.T.; Fuel, 1976.55.217, Saini, A.K.. Song, C., Schobert. H.H., and Hatcher, P.G.; ACS Fuel Chem. Prepr.. 1992, 37(3), 1235. Sokowiak, Mand Painter, P.; Fuel, 1992, 71, 1105. Song, C., Schobert. H.H.and Hatcher. P.G.; ACS Fuel Chem. Prepr.. 1992,37(2), 638-645; Energy & Fuels, 1992.6. 326-328. Table 1. Ratios of the amounts of the phenolic compounds to the alkylbenzenes. Dryiig conditions Unreacted Coal Residues Thermal I Catalytic I I I Raw 3.8 1.9 Air-dricd,u. Io0 3.5 2.0 Airdried.20h.100°C 2.5 2.4 Air-dried, 100h. 1WC 2.3 2.0 Airdried,20h. 150T 1.1 1.2 VaCUUm-driCd UdiD 3.6 2.2 Raw 2.5 *dri42hJ00 Airdried.ZOh.1WT Airdri4100h.lWC Air-dried.ZOh.l5OT VaClIUmdIiCd 3.3 2.8 2.2 1.4 3.1 Raw AiIdIiCd,Zh.100 Airdried.Z@ I OOT Airdried. 100h.IWC 2.2 2.4 2.4 1.5 Airdried,Xlh,lSPC VSCUUm-d+d 1.3 1.8 605 2.8 2.8 26 2.2 1.6 2.4 2.9 3.7 3.3 2.6 1.5 3.1 2.0 2.7 2.8 2.3 1.1 2.3
Page 1 and 2:
LIQUEFACTION PATHWAYS OF BITUMINOUS
Page 3 and 4:
the conversion of A+P and O+G with
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Asphaltcncs PrCasphaltenCS Cwr%, da
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NEW DIRECTIONS TO PRECONVERSION PRO
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ecause of incorporation of the coal
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should be considered more. The step
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17 18 Run no. 0 cys I ToS-CyS TS-To
Page 15 and 16:
INTRODUCTION Effects of Thermal and
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apid decline in modulus. The loss m
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-0.01- . 04 5 -0.03- E 6 -0.0s- c)
Page 21 and 22:
Assessment of Small Particle Iron O
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yields are calculated by subtractin
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conversion is greater than the corr
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Table 3. Effect of Superfine Iron O
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EFFECT OF A CATALYST ON THE DISSOLU
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inherent volatility of Mo(CO), perm
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Analysis of the quantity and compos
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$ EO .- 0 m L 0 c 0 0 > 40 300 350
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0 0 0 0 0.000 0.005 0.010 0.015 0.0
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of these studies indicate that cont
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Different levels of adsorption occu
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Nominal 2 Table 1. Concentration of
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- iF m 1.6 1.4 1.2 - - - 1- 0 0.8 -
Page 47 and 48:
RESULTS AND DISCUSSION Swelling of
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. . % . . 9 'HF 0 0 0 *. . 0 . . 0
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1.50 KQ 1.00 0.50 I / ' 02 525 I 1
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hydrogen atoms. The hydrogen atoms
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D to generate more D atoms. It is r
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12. a. Poutsma, M. L.; Dyer, C. W.
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Figure 3. Minimum Steps to Explin D
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Apoaratus and Procedure Microflow R
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Model ComDound Test Figure 5 shows
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Figure 1. High resolution gas chrom
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Figure 5. Product distribution for
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THQ at somewhat higher temperatures
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areas of the particles and the SEM
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Experimental Catalyst Precursors an
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impregnating solvent. Table 3 shows
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of MoCo-TC2 at the level of 0.5 wt%
Page 79 and 80: Table 4. Effect of Temperature Prog
Page 81 and 82: In the past, chemical treatments in
Page 83 and 84: The effect of Corn20 preaatment on
Page 85 and 86: Reaction Time Figure 1 - Schematic
Page 87 and 88: DISSOLUTION OF THE ARGONNE PREMIUM
Page 89 and 90: A much more def~tive trend is seen
Page 91 and 92: EFFECT OF CHLOROBENZENE TREATMENT O
Page 93 and 94: same conditions and an extraction t
Page 95 and 96: ACKNOWLEDGEMENT The authors thank t
Page 97 and 98: THE STRUCTURAL &=RATION OF HUMINlTE
Page 99 and 100: to be originally derived from demet
Page 101 and 102: 145 30 I --/---Jh I , , I I , 250 2
Page 103 and 104: THE EFFECTS OF MOISTURE AND CATIONS
Page 105 and 106: 1 for the Zap lignite. These result
Page 107 and 108: content of the samples ion-exchange
Page 109 and 110: Table 1. F'yrolysis Results of Vacu
Page 111 and 112: 585 I
Page 113 and 114: EFFECT OF TEMPERATURE, SAMPLE SI2E
Page 115 and 116: of some of the thermobalance runs.
Page 117 and 118: 2. The mechanism of drying is a uni
Page 119 and 120: Influence of Drying and Oxidation 0
Page 121 and 122: "c gives W conversion mpared to the
Page 123 and 124: Table 1. Products dismbutions (dmmf
Page 125 and 126: - 50 45 40 E 35 2 30 E T) 25 ap 20
Page 127 and 128: Influence of Drying and Oxidation o
Page 129: FTIR . . of the L m To investigate
Page 133 and 134: A b S 0 r b a n C e A b s 0 r b a n
Page 135 and 136: An NMR Investigation of the Effd of
Page 137 and 138: for determining the area of the pea
Page 139 and 140: of the ronl roniponcnte nnd (2) the
Page 141 and 142: 2w 180 160 9 140 120 P loo f 80 P O
Page 143 and 144: 25 I 20 ' + 0 Drying lime, hours Fi
Page 145 and 146: substructure have been identified a
Page 147 and 148: Pyridine extraction showed that 60
Page 149 and 150: Figure 1. Reflected white-light pho
Page 151 and 152: Table 3. Pyridine Extraction Sample
Page 153 and 154: A bang-bang control strategy was us
Page 155 and 156: increased from 120°C to 135”C, r
Page 157 and 158: * wt% based on the amount of naphth
Page 159 and 160: Use of Biocatalysts for the Solubil
Page 161 and 162: Results Enzyme Modification with Di
Page 163 and 164: Conclusions Reducing enzymes can be
Page 165 and 166: Dynamics of the Extract Molecular-W
Page 167 and 168: where yi = (x-xi !/pi. The zero mom
Page 169 and 170: satisfactory agreement between theo
Page 171 and 172: 0.8 0.6 0.4 0.2 “E \ bo Y, - 1 0
Page 173 and 174: The Use of Solid State C-13 NMR Spe
Page 175 and 176: differences lie in the fact that th
Page 177 and 178: I- z W 0 K W n PROTONATED AROMATIC
Page 179 and 180: ZAP WIO SIDE CHAINS IN PYRIDINE EXT
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ORGAFlIC VOLATILE MATER AND ITS SUL
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(Figure 1). They indicated that the
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Table 3. Elemental analysis of arom
Page 187:
1- 700'C Figure 3. GClFID chromatog
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