liquefaction pathways of bituminous subbituminous coals andtheir

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EXPERIMENTAL The following procedure was applied to all eight of the monne Premium Coal Samples. Approximately 20 g of coal was stirred in 100 ml concentrated HCl and 100 ml 48% HF under a N2 amosphere in a teflon container for at least 48 hours. After dilution to 1.5 1 with distilled water, it was filtered through acid-hardened filter paper, the residue was washed off the paper and, subsequently, filtered through a sintered glass funnel, washed acid-free and vacuum dried at 100 "C for 16 hours. An ash determination was made on the dried product. The demineralized coal was refluxed in pyridine for 10 hours. After cooling, the residue was separated by centrifuging and decantation. The residue was stirred in 5% HCI heated to 80°C for 2 hours. filtered, washed acid-free with distilled water, then methanol and, finally, vacuum dried at 100 OC for 16 hours. The pyridine solution was roto-evaporated to dryness and the pyridine soluble material was treated in the same maimer as the insoluble: hot 5% HCI but no methanol rinse. Ten grams of the pyridine extracted residue was added to a 100 ml solution of 10 g KOH and dissolved in ethylene glycol in a 300 ml stirred Parr reactor. The reaction mixture was heated to 250 OC for 2 hours and cooled. After dilution to 1 1, the mixture was heated to 60 "C and filtered. washed alkaline-free, and the residue vacuum dried at 100 "C for 16 hours. The residue was then successively extracted by refluxing for 2 hours in hexane, 1:l benzenc-methanol, and pyridine. The filtrates were roto-evaporated to dryness and vacuum dried at 60 O C for 16 hours. The pyridine soluble and insoluble residues were washed as described above with 5% HCI and vacuum dried 2 100 'C for 16 hours. RESULTS AND DISCUSSION The solubility yields from the KOH in glycol reaction are shown in Figure 1. The pyridine soluble yields are a combination of the yield of pyridine solubles prior to the reaction added to the pyridine solubles produced during the reaction of the extracted coal. This reaction produces (typically less than 1%) of very small, non-polar molecules which would be soluble in hexane. Indigenous molecules of this type would have been removed prior to the reaction by the initial pyridine extraction. Apparently, the extensive bond breaking which occurs at higher temperatures such as in pyrolysis and liquefaction is not taking place under those reaction conditions. In addition, the recovery tm 80 80 40 P 0 . . . . . 74.1 78 80.7 81.3 06 06.5 00.4 91.8 Xcsbon Figure 1. Yields from the ethylene glycol-KOH treatment of the Argonne Premium Coals. weights were very close to 100%for all of the samples. Very little sample weight was lost to small molecules or gained from the addition of the solvent to the products. 562
A much more def~tive trend is seen for the decrease in soluble product yields as a function of increasing rank than in the previous study.' In the original study, surprisingly, only 60% of the lignite products were soluble. However, this lignite coal was highly oxidized and had not been stored under premium conditions as is the case with the present samples. This procedure is obviously very effective for the lower rank coals. There are significant yields of bemneMeOH solubles in the three lowest rank coals. These mixtures are typically much more amenable to characterization than the pyridine extracts. There is good correlation with oxygen content as is shown in Figure 2. This is expected since it is likely that cleavage of ether linkages is one of the important mechanisms of solubilization. The Utah coal is much more reactive than expected from its oxygen content. However, this coal tends to be much more reactive than one would expect from its rank, such as in vacuum pyrolyis.' Also, this result implies that oxygen functionality is only partially responsible for the mechanisms of solubilization for this reaction. * * The Lochmann's base reaction yields 0 5 10 15 20 5 the opposite rank trend compared to OxySens/1 OM: the KOWglycol approach. For the subbituminous coal, which has ken Figure 1. Yields as a hction of oxygen content for the ethylene methylated, the pyridine solubility glycol-KOH reaction. increases only to 4% from 35s6, while for the high rank Pocahontas coal (AF'CS 5). pyridine solubility increases dramatically from 2.5% to 55% upon treatment with the base? These results suggest that these two different base treatments can be. used in parallel to produce a very soluble set of samples for the complete set of Argonne Premium Coal Samples. Mass spectral data from both LDMS and DCIMS, along with FTIR data are being analyzed for this complete set of samples from the KOH glycol solubdization. ACKNOWLEDGMENT This work was performed under the auspices of the Office of Basic Energy Sciences, Division of Chemical Sciences, US. Department of Energy, under contract number W-31-109-ENG-38. 563
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LIQUEFACTION PATHWAYS OF BITUMINOUS
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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
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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)
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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
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: DISSOLUTION OF THE ARGONNE PREMIUM
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
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of the ronl roniponcnte nnd (2) the
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2w 180 160 9 140 120 P loo f 80 P O
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25 I 20 ' + 0 Drying lime, hours Fi
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substructure have been identified a
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Pyridine extraction showed that 60
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Figure 1. Reflected white-light pho
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Table 3. Pyridine Extraction Sample
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A bang-bang control strategy was us
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increased from 120°C to 135”C, r
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* wt% based on the amount of naphth
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Use of Biocatalysts for the Solubil
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Results Enzyme Modification with Di
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Conclusions Reducing enzymes can be
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Dynamics of the Extract Molecular-W
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where yi = (x-xi !/pi. The zero mom
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satisfactory agreement between theo
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0.8 0.6 0.4 0.2 “E \ bo Y, - 1 0
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The Use of Solid State C-13 NMR Spe
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differences lie in the fact that th
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I- z W 0 K W n PROTONATED AROMATIC
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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
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1- 700'C Figure 3. GClFID chromatog
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