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Energy & Fuels 2002, 16, 62-68
Effect of Associative Interaction on the Dynamic Viscoelastic Property of Coal Concentrated Solution† Koyo Norinaga,* Masahiro Kuniya, and Masashi Iino Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Sendai 980-8577, Japan Received July 6, 2001. Revised Manuscript Received October 16, 2001
Coal concentrated solutions were prepared by dissolving pyridine soluble portions of Upper Freeport (UF) and Illinois No. 6 (IL) coals into N-methyl-2-pyrrolidinone (NMP). Gellike materials, that are not macroscopically phase separated, were produced at concentrations ranged between 30 and 50 wt % coal extract. Viscoelastic properties of the materials were characterized by means of controlled strain oscillatory rheometry at temperatures ranging from 223 to 273 K. An application of the time-temperature superposition rule allowed construction of master curves at reduced temperatures empirically, yielding data for the frequency dependencies of the modulus over a wide range, i.e., 10-6-106 Hz. The moduli of the viscoelastic materials formed from IL were larger than those from UF at equivalent temperature and frequency, principally because of the larger number of hydroxyl groups in IL extract than UF extracts. Effects of hydrogen bonds and aromatic-aromatic interactions on the viscoelastic properties were examined through O-methylation and hydrogenation of the extracts. Both modifications reduced the moduli of the materials, but affected the viscoelastic properties in different ways. Effect of hydrogen bonds on the dynamic modulus was more significant at higher frequencies, whereas the effect of aromaticaromatic interactions was more significant at lower frequencies.
Introduction Coal derived materials such as coal extracts and liquefaction products are known to readily associate and form aggregate or micelles in organic solvents.1-3 Some coal molecules contain functional groups that have either donating or accepting capabilities. These groups form aggregates through hydrogen bonds, ionic attraction, interaction between aromatics, and so forth. It can be expected that the coal solution would be capable of forming a kind of network structure through these interactions, as has been observed in many polymer solution systems.4 This type of network is called thermoreversible gel, since the associative, or noncovalent interactions forming the junctions where network chains join together, can break and recombine under thermal fluctuation. A systematic study by rheological methods is expected to be a most appropriate approach for getting useful information as to the coal-solvent and coal-coal interactions resulting from the nature of constituent molecular species. The thermoreversible gels exhibit simultaneous elastic and viscous behavior under most
conditions, and can be treated as a viscoelastic material. To characterize such materials accurately, both elastic and viscous responses must be measured. Dynamic mechanical analysis is therefore a uniquely powerful method because it measures both properties simultaneously. The gel formations in solven-swollen coal have been reported by Hall and Larsen.5 Larsen and coworkers5-7 demonstrated that highly swollen coals (extracted residues) have a glass transition temperature near 210 K. Brenner8-10 and Cody et al.11-13 found that when swollen in good solvent, coals show distinct rubbery characteristics at room temperature. However, there is little information available on the gels formed from coal concentrated solutions and their viscoelastic properties. This paper reports on the preparation of thermoreversible gels from coal extracts and organic solvent mixtures and the viscoelastic properties of the resultant gellike materials. The effects of the hydrogen bonding interaction and the interaction between aromatic rings on the dynamic viscoeasticities are also examined through the O-methylation and the hydrogenation of the coal extracts.
* Author to whom all correspondence should be addressed. Fax: +81-22-217-5655. E-mail:
[email protected]. † A preliminary account of this work has appeared in Energy & Fuels (ref 1). (1) Norinaga, K.; Kuniya, M.; Iino, M. Energy Fuels 2000, 14, 1121. (2) Stenberg, V. I.; Baltisberger, R. J.; Patal, K. M.; Raman, K.; Woolsey, N. F. In Coal Science; Gorbaty, M. L., Larsen, J. W., Wender, I., Eds.; Academic Press: New York, 1983; Vol. 2, p 125. (3) Iino, M.; Takanohashi, T. In Structures and dynamics of asphaltenes; Mullins, O. C., Sheu, E. Y., Eds.; Plenum Press: New York, 1998; Chapter VI, p 203. (4) Guenet, J. M. Thermoreversible Gelation of Polymers and Biopolymers.; Academic Press: London, 1992.
(5) Hall, P. J.; Larsen, J. W. Energy Fuels 1993, 7, 47. (6) Yang, X.; Larsen, J. W.; Silbernagel, B. G. Energy Fuels 1993, 7, 439. (7) Yang, X.; Silbernagel, B. G.; Larsen, J. W. Energy Fuels 1994, 8, 266. (8) Brenner, D. Nature 1983, 306, 772. (9) Brenner, D. Fuel 1984, 63, 1324. (10) Brenner, D. Fuel 1985, 64, 167. (11) Cody, G. D.; Davis, A.; Hatcher, P. G. Energy Fuels 1993, 7, 463. (12) Cody, G. D.; Davis, A.; Hatcher, P. G. Energy Fuels 1993, 7, 455. (13) Cody, G. D.; Painter, P. C. Energy Fuels 1997, 11, 1044.
10.1021/ef010154f CCC: $22.00 © 2002 American Chemical Society Published on Web 12/12/2001
Dynamic Viscoelastic Property of Coal Concentrated Solution
Energy & Fuels, Vol. 16, No. 1, 2002 63
Table 1. Properties of Coal Extracts extracts
C [wt %]
H [wt %]
N [wt %]
S [wt %]
Oa [wt %]
OHb [mol/kg-extracts]
Mwc [g/mol]
Mnd [g/mol]
Mw/Mn [-]
density [g/cm3]
UFPS UFPSHy ILPS ILPSmethyl
86.7 79.4 75.9 76.7
5.4 5.5 5.5 5.8
1.6 1.5 1.6 1.4
1.8 2.6 2.1 1.8
4.6 11.0 14.9 14.3
0.9 3.5 -
1520 1180 -
1070 750 -
1.4 1.6 -
1.217 1.224 1.171
a By difference. b Amount of hydroxyls determined by Blom’s method. c Weight-averaged molecular weight. d Number-averaged molecular weight.
Experimental Section Coal Extracts. Argonne Premium Upper Freeport and Illinois No. 6 coals14 were dried in a vacuum at 333 K. Solvent extraction of the dried Upper Freeport and Illinois No. 6 coals (hereafter referred to as UF and IL, respectively) follows the procedure of Iino et al. 15 UF was extracted with a 1:1 mixture (by volume) of N-methyl-2-pyrrolidinone (NMP) and carbon disulfide (CS2). The mixed solvent extract was extracted with acetone to remove NMP and CS2 that were strongly retained and the residue was further fractionated into pyridine solubles (UFPS) and insolubles. IL was extracted with pyridine and subsequently fractionated into acetone solubles and insolubles (ILPS). The yields of UFPS and ILPS were 18 and 15 wt % on a dry-ash-free basis, respectively, and were used for the gel preparations. The methylated ILPS (ILPSmethyl) was prepared using the partially modified Liotta’s method 16 that was proposed by Cody et al.17 A 1 g sample of the ILPS and 24 mL of THF (inhibitor free) were introduced to Erlenmeyer flask and the contents were stirred for 30 min. A 5.6 g sample of 40% KOH aqueous solution was added slowly to the mixture while stirring mechanically using a buret. After 2 h stirring, 1 mL of CH3I was added and the slurry was stirred for 24 h. THF and unreacted CH3I were evaporated from the slurry by using a rotary evaporator. The remaining aqueous solution was brought to neutral pH by adding 0.5 N HCl. The precipitated coal sample was then washed with deionized water for at least four cycles. The final product was dried to a constant weight in a vacuum oven set at 353 K. The hydrogenation of the aromatic rings in UFPS was accomplished by the method proposed by Takagi et al.18 A 0.4 g sample of UFPS was suspended in a mixture of 3 mL of acetic acid and 6 mL of THF. Hydrogenation was then performed using 0.5 g of an alumina-supported ruthenium catalyst at 393 K for 72 h under a hydrogen pressure of 10 MPa, in a 25 mL autoclave equipped with a magnetic stirrer. After hydrogenation, the catalyst was separated by centrifugation, and the acetic acid was removed by washing with water. The hydrogenated UFPS is hereafter referred to as UFPSHy. The elemental compositions, the average molecular mass determined by a laser desorptionionization mass spectrometry, and the density determined by pycnometry of the coal extracts are shown in Table 1. The detailed procedures of the measurement of molecular mass distributions 19,20 and densities 21 are given elsewhere. Gel Preparation. A 200 mg sample of the coal extract was introduced to glass tube and then a known amount of N-methyl-2-pyrrolidinone (NMP) was charged into the glass tube. The tube was connected to a vacuum system and the content was (14) Vorres, K. S. User’s Handbook for the Argonne Premium Coal Sample Program; Argonne National Laboratory: Argonne, IL, 1993. (15) Iino, M.; Takanohashi, T.; Ohsuga, H.; Toda, K. Fuel 1988, 67, 1639. (16) Liotta, R. Fuel 1979, 58, 724. (17) Cody, G. D.; Thiyagarajan, P.; Botto, R. E.; Hunt, J. E.; Winans, R. E. Energy Fuels 1994, 8, 1370. (18) Takagi, H.; Isoda, T.; Kusakabe, K.; Morooka, S. Energy Fuels 2000, 14, 646. (19) Norinaga, K.; Iino, M. Energy Fuels 2000, 14, 929. (20) Takahashi, K.; Norinaga, K.; Masui, Y.; Iino, M. Energy Fuels 2001, 15, 141. (21) Wargadalam, V. J.; Norinaga, K.; Iino, M. Energy Fuels 2001, 15, 1123.
frozen with liquid nitrogen. The freeze-thaw cycles were repeated for several times to remove the reactive gas trapped in the mixture. After the freeze-thaw cycles, 13 kPa of nitrogen was introduced to the tube. The tube was sealed and placed in an air bath kept at 353 K for at least 72 h to ensure a thorough homogenization of the contents. After the treatment, the tube was cooled to ca. 253 K. The firm gel formation was confirmed by observing that the sample did not flow when the tube was inverted and that the sample was not macroscopically phase separated. The NMP to coal extracts mass ratio (S/C) of the sample was determined after the measurement from the mass change observed upon heating at 423 K in a vacuum until it attains a constant weight. The S/C of the gel samples ranged from 1.1 to 1.9. To examine the effect of crystallization of NMP on the observed gelation, thermal properties of the gel samples were measured by a differential scanning calorimeter (Shimadzu DSC-50) at temperatures ranging from 120 to 400 K. We detected no endothermic processes arisen from the melting of NMP, confirming that NMP molecules are retained in nonfreezable form. This confirms that NMP crystallization has no influence on the observed gelation. Dynamic Viscoelastic Measurement. Rheological measurements of the gel samples were performed using a controlled stress rheometer (Rheometric Scientific Inc., ARES2KSTD) equipped with parallel plates. Frequency sweeps from 0.05 to 50 Hz were performed at temperatures ranging from 213 to 273 K with 7.85 mm (in diameter) plate. The thickness of the sample was 1.5-1.8 mm. Strain sweeps were previously performed to ensure that the viscoelastic response was linear and strain value of 0.05% was consequently chosen. FTIR Measurements. Diffuse reflectance FTIR spectra were recorded on a spectrometer (JEOL JIR-100) at a resolution of 4 cm-1 by co-adding 200 scans. Samples for FTIR experiment were prepared by diluting approximately 5 mg of coal sample in 200 mg of KBr.
Results and Discussion The measured dynamic modulus of rigidity was resolved into storage and loss components. The storage (elastic) modulus, G′, represents the portion of the oscillation energy that is stored elastically, whereas the loss (viscous) modulus, G′′, represents the energy dissipated by the system. Results of the frequency sweep experiments for ILPS/NMP and UFPS/NMP are shown in the form of log-log plots of G′ and G′′ against frequency (w), in Figures 1 and 2. Generally the G′ and G′′ decrease with temperature and lower w. The w dependencies of the moduli become more significant with increasing temperature. The data have been analyzed using the reduced variable time-temperature superposition procedure of Ferry 22 to yield so-called master curves. Data are reduced to the midrange temperature of the measurements performed for the samples, namely 243 K. The master curves obtained (22) Ferry, J. D. Viscoelastic Properties of Polymers; Wiley: New York, 1961.
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Figure 1. Storage (G′, top) and loss (G′′, bottom) moduli of UFPS/NMP(S/C ) 1.48) as a function of both the temperature and the oscillation frequency (w).
Figure 2. Storage (G′, top) and loss (G′′, bottom) moduli of ILPS/NMP(S/C ) 1.41) as a function of both the temperature and the oscillation frequency (w).
with respect to G′ are shown in Figure 3, in which the reduced frequency scales extend from 10-6 to 103-105 Hz. Though the application of the time-temperature superposition rule to the concentrated solution of the complex coal derived materials is questionable at present, a single composite curve can empirically be drawn by the horizontal shifts of the viscoelastic functions on logarithmic plots. The moduli decrease and the w dependencies of the moduli become more significant with increasing S/C for both UFPS/NMP and ILPS/ NMP. The master curve shows the time dependence (in terms of frequency) of the material at a constant reference temperature. The temperature dependence of the viscoelastic properties is shown by the variation of the shift factor with temperature. It is found that the temperature dependence of the shift factor can be well described by the Arrhenius equation as shown in Figure 4. The apparent activation energies of the viscoelastic mechanisms were calculated on the basis of the Arrhenius equation and are given in Table 2. It seems that the activation energy decrease with increasing S/C. The diluting effects of NMP are likely to make the gel samples less stable and easier to deform and flow under the applied stress at higher S/C. The master curves of the samples have no rubbery plateau regions that are observed in permanently cross-
linked polymer or highly entangled polymer melt or concentrated solution. In the frequency or time scales accessible by the present conditions, the gel samples respond differently with varying the oscillation frequency. The weight averaged molecular masses of UFPS and ILPS are estimated to be 1500 and 1200, respectively, by laser desorption mass spectrometry (Figure 5). Coal is known to consist of various types of aromatic rings linked by methylene or ether oxygen groups. As suggested by Painter et al.,23 even though the aromatic rings are linked by small sequences of flexible units, these structure would still not be particularly flexible, since conformational changes in the flexible sequences would require displacements of the rigid aromatic rings. Thus, the small molecular mass of the extracts and low flexible character of coal molecules make the highly chain entanglement impossible. The associative interactions among coal molecules themselves and between coal molecule and solvent would be key factors for the transient network formations in the coal concentrated solutions. However, in the case of coal molecules, it is diffficult to envisage how short, presumably highly branched chanins, could be involved in at least two junction zones (necessary for connectivity) and have a (23) Painter, P. C.; Graf, J.; Coleman, M. M. Energy Fuels 1990, 4, 393.
Dynamic Viscoelastic Property of Coal Concentrated Solution
Energy & Fuels, Vol. 16, No. 1, 2002 65 Table 2. Apparent Activation Energy for the Samples sample UFPS/NMP UFPSHy/NMP ILPS/NMP ILPSmethyl/NMP
S/C [-]
activation energya [kJ/mol]
1.13 1.48 1.66 1.11 1.19 1.41 1.88 1.13
191 132 156 158 202 182 172 172
a
Calculated by applying the Arrhenius equation to the data for temperature dependencies of shift factors.
Figure 3. Master curves of storage moduli (G′) at reduced temperature of 243 K for UFPS/NMP(top) and ILPS/NMP(bottom).
Figure 4. Plots for shift factors based on the Arrhenius equation. (VFPS/NMP)
sufficient length of flexible segments between these to provide elastic behavior. Therefore the observed rheological data is unlikely to be a direct result of associative interactions such as hydrogen bondings and interaction between aromatic rings acting as physical cross-links. The observed gelation would be related to freezing of molecular motion. Even if the origin of the observed
visocelastic behavior of the gels is not the associative interacitons, these interactions naturally influence the freezing phenomenon of constituent molecules and the observed viscoelastic behaviors are closely related with the nature of associative intractions. The mechanism of the formation of viscoelastic materials from coal extracts and NMP mixtures is still unclear and remains to be solved. Figure 6 compares the G′ master curves of UFPS/ NMP(S/C ) 1.48) and ILPS/NMP(S/C ) 1.41). G′ range from 104 to 107 Pa for UFPS/NMP and 106 to 108 Pa for ILPS/NMP, respectively, at reduced temperature of 243 K. It is noted that the moduli of the gel formed from ILPS are always larger than that from UFPS at equivalent temperatures and frequencies, though the S/C of both gels are almost equivalent. Figure 7 shows FTIR spectra of ILPS and ILPS/NMP. A broad band at around 3000-3600 cm-1 arisen from stretching vibration of hydroxyl in ILPS shifts to lower wavenumber regions when ILPS is mixed with NMP to form a gel. A peak arisen from stretching vibrations of carbonyls in NMP is also shifted from 1690-1685 cm-1 for pure NMP to 1666 cm-1 for ILPS/NMP. These observations reveal the formations of hydrogen bonds between coal extracts and NMP. Green and Tobolosky 24 proposed the simplest theory of transient networks in which the network junctions can break and recombine by thermal motion of the polymers and/or under applied deformation. Their theory predicts, G′∞ ) neffkBT, where, G′∞ is the highfrequency storage modulus, neff the number of elastically effective chains in the network, kB the Boltzmann constant, T the absolute temperature. Following this theory, the modulus is proportional to neff at same temperature. G′ of the ILPS/NMP is approximately an order of magnitude larger than G′ of the UFPS/NMP at high-frequency regions, suggesting that ILPS/NMP has more elastically effective chains in the transient network than UFPS/NMP does. The numbers of phenolic hydroxyls in the extracts samples were quantified following the method proposed by Blom et al.25 and to be 0.9 and 3.5 mol/kg-extracts for UFPS and ILPS, respectively (Table 1). The large abundance of hydroxyls in ILPS implies that the large probability of hydrogen bonding interactions between coal molecules or between coal molecules and NMP. And this is the one of the reason ILPS/NMP has more elastically effective chains and shows higher stability than does UFPS/NMP. To get further insight into the effect of hydrogen bonds on the dynamic viscoelasticity of the gel formed (24) Green, M. S.; Tobolsky, A. V. J. Chem. Phys. 1946, 14, 80. (25) Blom, L.; Edelhausen, L.; van Krevelen, D. W. Fuel 1957, 36, 135.
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Figure 5. Laser desorption mass spectra for UFPS (top) and ILPS (bottom).
Figure 6. Comparison of master curves of storage moduli (G′) at reduced temperature of 243 K for UFPS/NMP(S/C ) 1.48) and ILPS/NMP(S/C ) 1.41).
Figure 7. FT-IR spectra of ILPS and ILPS/NMP.
from coal extract and NMP mixture, the O-methylated ILPS (ILPSmethyl) was prepared to remove any effect due to hydrogen bonding interactions. Figure 9 shows FTIR spectra of ILPSmethyl and ILPSmethyl/NMP. The broad peak arisen from OH stretching vibration is significantly diminished in size by the methylation, indicating that a nearly complete derivatization of hydroxyl groups is accomplished. A peak coming from
stretching vibrations of carbonyls in NMP is observed at 1689 cm-1 in the spectrum of ILPSmethyl/NMP, the same wavenumber for carbonyls of pure NMP, implying that no hydrogen bonding interaction is occurring. Figure 9 demonstrates the effect of the methylation on the G′ master curve of ILPS/NMP. G′ of ILPS/NMP is larger than G′ of ILPSmethyl/NMP over the frequencies accessible in the present experiments, though the S/C
Dynamic Viscoelastic Property of Coal Concentrated Solution
Figure 8. FT-IR spectra of ILPSmethyl, and ILPSmethyl/ NMP.
Figure 9. Comparison of master curves of storage moduli (G′) at reduced temperature of 243 K for ILPS/NMP(S/C ) 1.19) and ILPSmethyl/NMP(S/C ) 1.13).
of both gels are almost equivalent. Complex formations between coal molecules or between coal molecules and NMP via hydrogen bonds are almost completely removed by the O-methylation as revealed by the FTIR spectra of ILPSmethyl/NMP. As a consequence, the stability of ILPSmethyl/NMP is lower than that of ILPS/ NMP, thereby decreasing the modulus. A similar observation is also reported by Freitas et al.26 for the thermoreversible polymer networks functionalized by polar stickers. They modified the properties of polybutadiene by attaching the urazole groups, which form hydrogen-bonded pairs, with polybutadiene backbone. Dynamic viscoelastic measurements were carried out for the modified and unmodified thermoreversible networks. They found that the rubbery plateau is lengthened in frequency and the storage modulus is increased with increasing the number of the introduced urazole groups. It seems that the difference in G′ of ILPS/NMP and ILPSmethyl/NMP becomes more significant at higher frequencies. Contrary to this, the effect of hydrogenation (26) Freitas, L.; Stadler, R. Macromolecules 1987, 20, 2478.
Energy & Fuels, Vol. 16, No. 1, 2002 67
Figure 10. Comparison of master curves of storage moduli (G′) at reduced temperature of 243 K for UFPS/NMP(S/C ) 1.13) and UFPSHy/NMP(S/C ) 1.11).
of aromatic rings is more pronounced at lower frequencies as shown in Figure 10. Both methylation and hydrogenation decrease the stabilities of the coal thermoreversible gels but they affect the viscoelastic properties of the gels in different ways. This would be attributed to differences in the nature of hydrogen bonds and interactions between aromatics occurring in the unmodified coal gels. Muller et al. 27-29 showed that hydrogen bonds cannot act as cross-links unless the frequency of the experiment is in the same range as the time frame of hydrogen bond lifetimes, e.g., 10-5-10-6 s in the system they examined. This suggests that hydrogen bonds are related to the modes of molecular motions on local scales with relatively rapid response rates to the external stress. Thus, qualitatively speaking, the removal of hydrogen bonds influences the viscoelastic properties more extensively at higher frequencies. On the other hand, the lifetime of the aromatic-aromatic bonds is likely to be longer than that of hydrogen bonds, thereby showing more extensive decrease in modulus at lower frequencies. The interactions between aromatics are likely to associate with the modes of molecular motions on long-range scales with somewhat slow response rates to the external stress. However, the present hydrogenation is not complete and probably gives rise to undesirable reactions, increasing the oxygen content as indicated by the elemental analysis (Table 1). Therefore the observed phenomena would not be influenced solely by the hydrogenation of aromatic rings. The effects of the associative interactions on the apparent activation energies of the viscoelastic mechanisms are finally addressed. As listed in Table 2, the activation energies are decreased from 191 kJ/mol (UFPS/NMP, S/C ) 1.13) to 158 kJ/mol (UFPSHy/NMP) and from 202 kJ/mol (ILPS/NMP, S/C ) 1.19) to 172 kJ/mol (ILPSmethyl/NMP) by methylation and hydrogenation, respectively. The eliminations of the associative interactions between coal extracts or between coal (27) Muller, M.; Stadler, R.; Kremer, F.; Williams, G. Macromolecules 1995, 28, 6942. (28) Muller, M.; Seidel, U.; Stadler, R. Polymer 1995, 36, 3143. (29) Muller, M.; Kremer, F.; Stadler, R.; Fischer, E. W.; Seidel, U. Colloid Polymer Sci. 1995, 273, 38.
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extracts and NMP reduce the strength of coal thermoreversible networks or enhance the mobilities of constituent molecules, thereby lowering the energy barriers for the deformation and flow under applied stress. Conclusions Thermoreversible gels that are not macroscopically phase separated were prepared from the coal extracts (UFPS and ILPS) and NMP mixtures. Dynamic mechanical responses of the gels over a wide range of the time scales, ca. 10-6-106 Hz were obtained by the application of time-temperature superposition rule. Effect of the associative interactions on the viscoelastic properties of the gel samples were examined through O-methylation and hydrogenation of the coal extracts. Within the limits of the present experimental conditions, the following conclusions were made. (1) The dynamic storage modulus of ILPS/NMP is larger than that of UFPS/NMP, even if the S/C of both gels are almost equivalent. A larger probability of hydrogen bonding interactions between coal molecules or between coal molecules and NMP in ILPS/NMP than
Norinaga et al.
in UFPS/NMP due to the larger content of hydroxyls of ILPS than UFPS is responsible for this observation. (2) Both methylation and hydrogenation decrease the modulus of the gels but they affect the viscoelastic properties of the gels in different ways. The effect of hydrogen bonds on the dynamic modulus is more significant at higher frequencies, whereas the effect of aromatic-aromatic interactions is more significant at lower frequencies. Acknowledgment. The authors are grateful to Drs. Takaaki Isoda and Hideyuki Takagi of Kyushu University for providing the hydrogenated coal extracts samples. The authors are also grateful to Dr. Hiroyuki Seki of the Petroleum Energy Center for providing molecular mass distribution data of the coal extracts. This work was supported by a “Research for the Future Project” grant from the Japan Society for the Promotion of Science (JSPS), through the 148 Committee on Coal Utilization Technology. EF010154F
