liquefaction pathways of bituminous subbituminous coals andtheir

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soL-.--.+-.-.-< : . . . .---+.. 40 80 120 IBO 200 210 280 120 ltlo 400 440 Temperature ("C) 0.32- 2 1 '' 3 32n.. 2. I 0.20.. 22 f 0.18. 21 0.12. 20 Figure 4. DMA scan of the Upper Freeport medium volatile bituminous coal obtained at 4'C/min. Sample pellet was made from -100 mesh powder pressed at 15 kpsi for 12 hr. 01 4.01 4.03 E 4.05 Zmddrd In-2nd 1sb3rd 1 (a) Difference DSC 4.09 ' 1 (b) Solvent swelling '.O 1 /a Pyridim , .,I , s z 4.07 c (c) Weight loss 0 100 100 300 400 3 Temperature ("C) 494 0 I Figure 5. Difference DSC thermograms as well as profiles of solvent swelling ratio and weight loss obtained at 8'Umin from -100 mesh Upper Freeport coal powder (swelling time:0,5 k,O, 7 days).
Assessment of Small Particle Iron Oxide Catalyst for coal Liquefaction Richard Anderson, Edwin N. Givens and Frank Derbyshire University of Kentucky Center for Applied Energy Research 3572 Iron Works Pike, Lexington, KY 40511-8433 Keywords: Coal liquefaction, iron oxide, catalysis Introduction Current efforts to lower the cost of producing coal liquids are concentrated on the use of low-rank coal feedstocks, and dispersed catalysts to promote coal dissolution in the first stage of a two-stage process. Molybdenum and iron are the most commonly investigated catalyst metals, and precursors of both can be converted to an active sulfide catalyst under liquefaction conditions.' Although iron catalysts are less active, they are preferred for reasons of economy. A great deal of research has been spent in attempting to understand the chemistry of liquefaction in the presence of iron catalysts. It has also been demonstrated that the use of powdered iron catalysts has allowed the liquefaction of subbituminous coals which could not otherwise be processed'. Nevertheless, the activity of these catalysts is still much less than desired and means to enhance their activity are under investigation. The catalyst activity is determined principally by its composition and the extent of its dispersion with the coal or coal-solvent slurry. The catalyst dispersion is dependent upon the form and mode of addition of the catalyst precursor. High activities are reportedly favored by catalysts introduced as oil-soluble organometallic precursors such as naphthenates and carbonyls. 3s4s The results of some studies, however, indicate that even with these precursors, quite large crystallites or agglomerates can be formed during liquefaction and hence the potentially high dispersion is not maintained. There is some evidence to suggest that, if introduced as fine particulates, there is less tendency for agglomeration. Iron particles of about 50 nmmean diameter synthesized by a flame pyrolysis technique appeared to have retained their particle size and shape during presulfiding and coal liquefaction.'.' Other work has shown that FeS is more active as a colloid than in powder form.' A number of studies have reported enhanced catalytic activity by using methods of preparation that introduce nanometer size iron catalysts .9*10J1,12 The work presented in this paper is concerned principally with a systematic evaluation of the effect of reaction parameters on the catalytic conversion of a subbituminous coal using a commercially produced nanometer size iron oxide catalyst. The work is part of a DOE program to evaluate process concepts that can alone, or in concert, significantly improve process economics. In order to make realistic assessments, studies have been made using process recycle oil from the Wilsonville Advanced Coal Liquefaction Research and Development Facility and Black Thunder subbituminous coal. Materials Reasents - Reagents were purchased as follows: Practical grade dimethyl disulfide (DMDS) from Fluka AG; 99% purity W grade tetralin, high purity tetrahydrofuran (THF), and high purity pentane were Burdick & Jackson Brand from Baxter S/P; UHP 6000W hydrogen was supplied by Air Products and Chemicals, Inc. Coal, coal derived liquids and iron oxide used at the Wilsonville Advanced Coal Liquefaction Research and Development Facility were supplied by CONSOL, Inc. 495
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: -0.01- . 04 5 -0.03- E 6 -0.0s- c)
Page 23 and 24: yields are calculated by subtractin
Page 25 and 26: conversion is greater than the corr
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
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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
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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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