liquefaction pathways of bituminous subbituminous coals andtheir

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oxide caused an appreciable increase in conversion. l7 In both thermal and catalytic cases, the CO and C02 are formed at short times, and the yields increased only slightly between 15 to 60 minutes. In comparison, the hydrocarbon gas yield increased from 0.5 to 1.9 Wt%. Much of this increase in hydrocarbon gas yield comes from the conversion of recycle oil. Influence of Nanometer Size Iron Oxide ISFIO) - sulfided iron oxide particles in the size range 50-80 nm, that were prepared by high temperature thermal oxidation, have been reported to show high activity for coal liquefaction.6 The catalytic effect has been attributed to the high surface area and small particle size of the pyrrhotite formed upon sulfiding in the presence of coal where the pyrrhotite particles retain the small particle size of the oxide precursor.'8 The SFIO, whose very high surface area is consistent with nanometer size particles, may also, upon sulfiding, give rise to small particle, high surface area liquefaction catalysts. The addition of SFIO, at a loading of 2.5 wt% iron on maf coal, produced 11 wt% more oils than in the thermal case (see Table 3). In addition there were slight increases in THF conversion and yield of hydrocarbon gases. These data represent the mid-point of the ranges for each of the three variables. The results of the comparison illustrate the potential advantage of processing with SFIO catalyst. 1;- The R squared values for each dependent variable that was selected indicate the degree of fit by the linear model coefficients as shown in Table 4. Values for the coefficients for each of the simple linear models are summarized in Table 5. The P-value of each coefficient is shown in parentheses. Of the independent factors, temperature has the strongest overall effect, as seen by the magnitude of the coefficients for THF conversion, hydrogen consumption, and the yields of oil and PA+A; the oil yield increases and PA+A decreases with increasing temperature. Increasing the catalyst concentration produces moderate effects on THF conversion, hydrogen consumption, and enhances the PA+A yield. However, there is no apparent effect of catalyst concentration on oil yield. It must be stressed that only two levels of catalyst concentration have been examined and the zero concentration case is not included: as shown in Table 3, the addition of catalyst significantly improves the oil yield over the thermal case. The effects of added sulfur are small, producing a weak negative coefficient with respect to THF conversion, and a negative coefficient with oil yield. The average increase in oil yield obtained in the three centerpoint experiments was 11% over the thermal case. This is consistent with the increase of 10 wt% in oil yield predicted by the Z3 factorial design experiments and lends confidence to the linear model. The addition of 1.1 wt% added iron as WIO, which was the ratio used in the Wilsonville plant, gave 5% more oil than in the thermal case, which agrees closely with the results observed at Wilsonville.17 The linear model predicts that SFIO at the lower concentration level (1.1 wt% Fe) will produce 15% higher oil yield than in the thermal case, with a decrease to the observed 11% gain at the center point due to the effect of added sulfur (see Table 6). However, the experimental check of this predicted outcome gave only 8% more oil than the thermal case. The catalytic activity of the SFIO for both oil formation and coal 498
conversion is greater than the corresponding activity of the WIO. The negative effect of sulfur on THF conversion and on oil ield was unexpected based upon the results of' DaS Gupta, et al.,' on the liquefaction of an iron deficient Indian coal. They found, through a non-linear parameter estimation procedure, that adding sulfur up to a SjFe atomic ratio of 8 improved conversion. In this system adding sulfur at a SfFe atomic ratio between 0.6 to 7.4 was detrimental. This effect could be related to adverse side reactions caused by the presence of excess sulfur. The negative interaction between temperature and SFIO concentration for oil yield indicates that thermal effects begin to dominate catalytic effects at the higher temperature. Also, in addition to thermal conversion of PA+A, the magnitude of the catalyst coefficient for the PA+A model (4.80 vs. 4.08 for THF conversion) suggests that catalytic IOM dissolution reports mainly to the PA+A fraction. References 1. Derbyshire, F. J., Catalysis in Coal Liquefaction, IEACRf08, London, UK, IEA Coal Research, 1988, 69pp. 2. Tomlinson, G. C., Gray, D., Neuworth, M. 8. and Talib, A., Report SAND85-7238, Albuquerque, NM, USA, Sandia National Laboratories, 105pp. 3. Hawk, C. O., Hiteshue, R. W., Hydrogenation of Coal in the Batch Autoclave. Bulletin 6322 Washington, DC, USA, US Department of the Interior, Bureau of Mines, 1965, 42pp. 4. Watanabe, Y., Yamada, O., Fujita, K., Takegami, Y. and Suzuki T., Fuel, 1984, 63, 752-755. 5. Suzuki, T., Yamada, O., Then, J. H., Ando, T. and Watanabe, Y., Proceedings - 1985 ICCS, Sydney, NSW, Australia, Pergamon Press, 1985, pp205-8. 6. Andres, M., Charcosset, H., Chiche, P., Davignon, L., Djega- Mariadassou, G., Joly, J-P. and Pregermain, S., Fuel, 1983, 62, 69-72. 7. Andres, M., Charcosset, H., Chiche, P., Djega-Mariadassou, G., Joly, J-P. and Pregermain, S., Preparation of catalysts I11 (Eds. G. Poncelet and P. Grange), Elsevier, 1983, pp675-682. 8. Nakao, Y., Yokoyama, S., Maekawa, Y. and Kaeriyama, K., Fuel, 1984, 63, 721. 9. Cugini, A. V., Utz, B. R., Krastman, D. and Hickey, R. F., ACS Div. Fuel Chemistry Preprints, 1991, 36 (l), 91. 10. Hager, G. T., Bi, X-X., Derbyshire, F. J., Eklund, P. C. and Stencel, J. M., ACS Div. Fuel Chemistry Preprints, 1991, 36 (4), 1900. 11. Pradhan, V. R., Tierney, J. W., Wender, I. and Huffman, G. P., Energy and Fuels, 1991, 5 (3), 497. 12. Huffman, G. P., Ganguly, B., Taghiei, M., Huggins, F. E. and Shah, N., ACS Div. Fuel Chemistry Preprints, 1991, 36 (2), 561. 13. Southern Electric International, Inc., Technical Progress Report, "Run 260 with Black Thunder Mine Subbituminous Coal", DOE Contract No. DE-AC22-90PC90033 and EPRI Contract No. RP1234-1-2, Document No. DOEfPC90033-16, January 1992. 14. Derbyshire, F., "Advance Coal Liquefaction Concepts for PETC Generic Bench-scale Unit', DOEjPCj91040-9, May 1992. 15. Box, G. E. P., Hunter, W. G. and Hunter, J. S., Statistics for Experimenters, John Wiley and Sons, New York (1978). 16. Anderson, R. R. and Bockrath, B. C., Fuel, 1984, 63, 329. 17. Southern Electric International, Inc., Technical Progress Report, IIIntegrated Two-Stage Liquefaction of Subbituminous Coal", DOE contract No. DE-AC22-82PC50041 and EPRI RP1234-1-2, 499
Page 1 and 2: LIQUEFACTION PATHWAYS OF BITUMINOUS
Page 3 and 4: the conversion of A+P and O+G with
Page 5 and 6: Asphaltcncs PrCasphaltenCS Cwr%, da
Page 7 and 8: NEW DIRECTIONS TO PRECONVERSION PRO
Page 9 and 10: ecause of incorporation of the coal
Page 11 and 12: should be considered more. The step
Page 13 and 14: 17 18 Run no. 0 cys I ToS-CyS TS-To
Page 15 and 16: INTRODUCTION Effects of Thermal and
Page 17 and 18: apid decline in modulus. The loss m
Page 19 and 20: -0.01- . 04 5 -0.03- E 6 -0.0s- c)
Page 21 and 22: Assessment of Small Particle Iron O
Page 23: yields are calculated by subtractin
Page 27 and 28: Table 3. Effect of Superfine Iron O
Page 29 and 30: EFFECT OF A CATALYST ON THE DISSOLU
Page 31 and 32: inherent volatility of Mo(CO), perm
Page 33 and 34: Analysis of the quantity and compos
Page 35 and 36: $ EO .- 0 m L 0 c 0 0 > 40 300 350
Page 37 and 38: 0 0 0 0 0.000 0.005 0.010 0.015 0.0
Page 39 and 40: of these studies indicate that cont
Page 41 and 42: Different levels of adsorption occu
Page 43 and 44: Nominal 2 Table 1. Concentration of
Page 45 and 46: - iF m 1.6 1.4 1.2 - - - 1- 0 0.8 -
Page 47 and 48: RESULTS AND DISCUSSION Swelling of
Page 49 and 50: . . % . . 9 'HF 0 0 0 *. . 0 . . 0
Page 51 and 52: 1.50 KQ 1.00 0.50 I / ' 02 525 I 1
Page 53 and 54: hydrogen atoms. The hydrogen atoms
Page 55 and 56: D to generate more D atoms. It is r
Page 57 and 58: 12. a. Poutsma, M. L.; Dyer, C. W.
Page 59 and 60: Figure 3. Minimum Steps to Explin D
Page 61 and 62: Apoaratus and Procedure Microflow R
Page 63 and 64: Model ComDound Test Figure 5 shows
Page 65 and 66: Figure 1. High resolution gas chrom
Page 67 and 68: Figure 5. Product distribution for
Page 69 and 70: THQ at somewhat higher temperatures
Page 71 and 72: areas of the particles and the SEM
Page 73 and 74: Experimental Catalyst Precursors an
Page 75 and 76:
impregnating solvent. Table 3 shows
Page 77 and 78:
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 and 130:
FTIR . . of the L m To investigate
Page 131 and 132:
CONCLUSIONS The characexizntion of
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
Page 181 and 182:
ORGAFlIC VOLATILE MATER AND ITS SUL
Page 183 and 184:
(Figure 1). They indicated that the
Page 185 and 186:
Table 3. Elemental analysis of arom
Page 187:
1- 700'C Figure 3. GClFID chromatog
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