In order to clarify the effect of pretreatment on liquefaction reactivity of coal, transferable hydrogen (TH) of coal cleaned by gravity separation method was assessed using anthracene as hydrogen acceptor. The amount of TH in River King coal decreased with increasing ash content. The amount of TH was not necessarily correlated with H/C atomic ratio. Organic part of IR spectra of coals was hardly changed by gravity separation. It was recognized that the higher the vitrinite content and the lower the inertinite content, the larger is the amount of TH. Correlations between the amount of TH and the liquefaction yields for the cleaned coal were observed. Except for River King coals, no simple correlation exists between the amount of TH and the total conversion in liquefaction of various coals. On the other hand, good correlation was obtained between the amount of TH and (Asphaltene+Oil) yield. TH is a desirable parameter in evaluating the liquefaction reactivity of coal. The amount of hydrogen requisite to depolymerization of coal was examined on the basis of the model assuming that coal is a simple polymer and was compared with the amount of transferable hydrogen.

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We tried to produce metallurgical coke from several non-coking and slightly coking coals by use of a hotbriquetting apparatus. Without loading pressure the coals were not caked when they were heated up to 500°C. However, the non-coking coals were caked when they were heated up to 500°C under the pressure larger than 10×10⁵Pa. The compressive strength of the cokes produced by carbonizing the caked coals up to 800°C was very strong, but the CO₂ reactivity of the cokes was very high, in comparison with a commercial coke. It is essential to load pressure on the coal between 300 and 450°C when the coal is pyrolyzed to a large extent. Thus, we could produce coke from non-coking coals, but not from coking-coals by this method. This is because the volatile matter could not be removed from coking-coals in a short time under the pressure.

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Fine iron sulfide particles were prepared in a vibrating ball mill by the reaction of iron ball with sulfur powder under high temperature and high pressure of hydrogen.
The iron sulfide was estimated to be produced on surface of ball by the following reactions.
H₂+S=H₂S
Fe+H₂S=FeS+H₂
During the reactions of hydrogenation, hydro-cracking and/or coal liquefaction, the particles of iron sulfide were worn simultaneously from sulfurized surface of iron ball in the vibrating reactor.
The iron sulfide particles were characterized as catalyst on reaction activity of hyd-rogenation of phenanthrene and coal liquefaction. The conversions of phenanthrene on hydrogenation and coal liquefaction increased with increase of the in-situ prepared catalyst. Yields of hexane solubles of coal liquids by the in-situ prepared catalyst were found to be equal or better than that by conventional catalyst of iron oxide and sulfur.
And hydrogen consumption by use of the in-situ prepared catalyst was less of that by the conventional catalyst at the same yield of coal derived oil.

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C₃-C₆ alkylphenols of 47 kinds were synthesized. Polymethylphe-nols were synthesized by transferring methyl groups from tetramethylbenzene to coexisting dimethylor trimethylphenols on asilicaalumina or a zeolite catalyst. Diethylphenols were synthesized transferring ethyl groups from diethylbenzene to coexisting ethylphenols on a silicaalumina catalyst. Other phenols were synthesized by allowing the phenols to react with alkyl bromide on aluminium chloride. The position of the alkyl group was determined by superposition of the reaction pathways. The 47 synthesized phenols and 26 commercial phenols were analyzed by GC-FID and GC-MS and their retention indices were calculated.

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The air-oxidation reactions of Taiheiyo coal were carried out under the relatively high temperatures (130, 170 and 213°C). The roles of hydrogen bond in terms of humic acid formation in the structure of oxidized coal were investigated from the pyridine and benzene extractabilities and the changes of IR spectra of the solvent extracts.
At 213°C, strong hydrogen bonds are formed within 10 hours from the beginning of oxidation, which is due to production of humic acids. Then, the elimination of the hydrogen bondings by the decomposition of carboxyls begins also immediately to release cluster between humic acid molecules and degraded coal structure. The apparent network structures linked ether oxygens are considerably difficult to be formed below 200°C.

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