liquefaction pathways of bituminous subbituminous coals andtheir

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Empirical Evaloation of Coal Amnity for Varioos Chemieals Tetsuo Aids*', Shuhsaku Suzuki', Masayuki Fujii' Masakuni Yoshihara', Teijiro Yonezawa2 'Department of Industrial Chemistry, Faculty of Engineering in Kyushu Kinki University 11-6 Kayanomori, lizuka, Fukuoka 820, JAPAN 'Department of Applied Chemistry, Faculty of Science and Engineering Kinki University 341 Kowakae. Higashi-Osaka 577. JAPAN INTRODUCTION Coal is a complicated natural product which has several functional groups in its cross- linked macromolecular structure. Because of this fact the diffusion mechanism of the penetrant molecule into the matrix of a solid coal is not so simple. It is quite important to know the affinity between the penetrant molecule and the macromolecular structure of coal for the coal scientists who are challenging to develope efficient chemical transformations of coal such as liquifaclion, gasification and etc.. Neverthless the reliable methodorogy to determine the affinity has not yet been developed. One of the most practical approach to this goal will be to use the solvent swelling behaviours of coal. Because as it is mostly true that better solvent makes coal better swelling, the equiliblium swelling value(Q-value) of the penetrant may reasonably reflect its affinity to the coal. However, there are some problems in this idea. One of the most critical problems will be how to determine the Q-value of solvents(chemicals) which used to be a solid(crysta1) under the measureing condition. Furthermore the steric bulkiness of the penetrant molecule also will provide an aserious error on the net Q-values(lJ. Some years ago, we revealed the steric requirement of coal toward the penetrant molecule is significantly relaxed in binary solvent system which is composed with normal solvent such as methanol or DMF and stericcally hindered molecule(ie., triethylamine or HMPA)(D. The mechanism of the relaxation of the steric requirement of coal is considered as follows; the preferential peteration of the normal solvent into solid coal makes the coal-solvent gel. Then. the significant expansion of the cross-linked network of coal is induced and thus it makes the bulky molecule easy to penetrate. These findings hinted us to use this swelling system for evaluating the affinity of various chemicals toward coal. This paper presents the results of the studies on the new methodorogy to evaluate the coal affinity of various chemicals. EXPERIMENTAL The swelling measurements were carried out as described into previous paper(3J. Coal, Illinois No.6 coal. used in these studies was from the Ames Laboratory Coal Library. Prior to use. the coal was ground. sized. dried at I IOOC overnight under vacuum, and stored under a nitrogen atmosphere. The solvents were distilled by orginary procedures before use. This work was supported by the grant from The Japanese Ministry of Education, during 1989-1992. 520
RESULTS AND DISCUSSION Swelling of Illinois No. 6 Coal in Various Solvent Coal swells in the various solvent with the different manners. Figure 1 shows the relation between the equiliblium swelling value of the solvent which were determined by our instrument and its electron donor numbedDN). This type of data treatment had been reported by Manec et al.(4J, and they recognized some correletion between them. Hoever as far as the data shown in this Figure. it seems to be quite difficult to find out such correlation. As we discussed before(l), one of the problems in this figure is that the Q-values measured always involve thier steric factor, that is, the sterically hindered solvents are restricted the penetration into the macromolecular structure of coal by the steric requirement, probably due to the cross-linking density. If in this Figure we can pick up only the solvents which are not sterically bulky and also have relatively high dielectric constant(>20), the correlation becomes very clear and almost lenear as shown in Figure 2. It is quite interesting that the dielectric constant of the penetrant also seems to be one of the key parameters controlling the coal affinity. This fact may suggest that there are the significant contribution to the macromolecular cross-linking structure of coal from relatively week bonding interactions such as van der Waals, hydrogen bonding, charge transfer bonding and IC-R bonding. Introduction of Coal Affinitv Parameter Although these data shown above suggest the possibility to use the equiliblium swelling value(Qva1ue) as a convenient scale for evaluating the affinity to the coal. there seems to be at least two big problems, that is, the first of all is how to determine the Q- value of solid chemicals(crysta1) by means of the solvent swelling measurement. and the second of all is how to eliminate the steric factor from the observed Q-value. Table I summerizes the swelling behaviours of Illinois No.6 coal in the steric isomers of butylamine. It is obvious that there is a significant steric equirement on their swelling which is reflected not only on the swelling rate(V-value), but also on the Q-value. Thus, the Q-value measured in the neat solvent always involves the contribution from the steric factor. Namely, in order to use the Q-value as a tool for evaluating the coal affinity, we have to find out the methdorogy to extract the net Q-value from the observed one. Figure 3 demonstrate the swelling behaviour of Illinlois No.6 coal in the binary mixture of the butylamine and methanol. In the case of n-butylamine-methanol system, the observed Q-values have a nice lenear relationship versus the concentration. Meanwhile in the mixed system of more sterically bulkier isomers such as sec- and tert- amine a kind of the synergistic effet were observed. It is particulary interesting that the values obtained by the extraporation(ditted line on the figure) from the Q-value at the lower ocnsentration reagion seems to reasonably reflect their own values. We had revealed this phenomena as the relaxation of the steric requirement by the coa-gel fomation(D. Now. we may be able to define for the extraporated values obtained on the Figure to be their potential Q-value(Qpt) which used to be hiddn by the steric factor. If these speculation are correct, we can use this swelling sytem as a general procedure for evaluating the coal affinity. Namely, as far as the chemicals are soluble in the solvent (reference solvent). gas, liquid even sold or crystal, the potential Q-value(Qpot) must be empirically determined by this method. Farthermore, very fortunately, because of the binary solvent system the steric factor in the observed Q-value can be minimized. Based on these considerations, we propose a new empirical parameter to evaluate the affinity to the macromolecular structure of coal, as the Coal Affinity Parameter(KQ) which is calculated following equation. 521
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 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: - iF m 1.6 1.4 1.2 - - - 1- 0 0.8 -
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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