Based on the fundamental understanding of the carbonization mechanism, some ideas for the development of anisotropic flow texture in the produced coke were reviewed. The co-carbonization process may be the most useful one which can develop the optical texture in any form from any carbonizing material, in principle, by means of suitable additive. In the best process, no modification of external conditions for the carbonization is requested to obtain a coke of best quality such as a prime needle coke. The compatibility of the co-carbonizing substances is introduced to explain and describe cather quantitatively the effect of co-carbonization. The efficiency of an additive is discussed from the view of its chemical structure and reactivity.

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The present status of the research and development in catalytic coal gasification was overviewed. First, the strategy for process design was examined from chemical viewpoints: equilibrium, kinetics, and thermal balance. This examination clarified that the usefulness of catalyst application was limitted to only certain steps among many reactions occurring in a gasifier. Factors affectors on the catalyst effectiveness were also discussed: the catalyst type, the amount of catalyst, the gasification temperature, and so on. Alkali metal salts were evaluated as the most active catalyst, followed by transition metal catalysts. The mechanism of catalytic reaction was briefly considered from a thermodynamic point of view. Finally, the problems were pointed out which we may encounter upon scaling up a catalytic process. Loading of catalyst on coal and its recovery from a char-ash-catalyst mixture may be the most important field to be considered.

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This paper deals with physical properties of solvolysis pitch which affect on the separation of ash from coal after solvolysis reaction. Softening point of solvolysis pitch and density and ash content of solvolysis pitch, its quinoline insoluble mattent (QI) and quinoline soluble matter (QS) were determined in connection with reaction conditions. The results obtained are summerized as follows.
(1) From the solvent extraction of solvolysis pitch, it was found that the increase in softening point of solvolysis pitch obtained at a temperature below 400°C was caused by dissolution of a part of coal into petroleum vacuum residue during heat treatment.
(2) The softening point of solvolysis pitch increased with a increase in heat treatment temperature and coal ratio used.
(3) The softening point of solvolysis pitch from various ranks of coals at 390°C for 60 minutes took a maximum value at 83% of carbon content of coal.
(4) The density of solvolysis pitch and its QS prepared from a part of Miike coal and two parts of Khafji vacuum residue increased gradually with a increase in heat treatment temperature. On the other hand, density of the QI took a maximum value of 1.6 at 390°C and ash content of QI took a maximum value of about 32% at the same temperature, too.

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Proton and carbon-13 nuclear magnetic resonance spectroscopies of various asphalts and their fractionated samples were carried out to investigate average molecular structures.
Aromaticity calculated from relative intensities of aromatic and aliphatic region of ¹³C NMR spectra was in fair agreement with that of calculated from proton distribution of ¹H NMR using Brown-Ladner method. The structural parameters derived from carbon distribution-number of unsubstituted aromatic carbon, that of substituted aromatic carbon, number of condensed aromatic carbon, etc.-agreed with those derived from ¹H NMR within experimental errors. In the aliphatic region of ¹³C NMR spectra, characteristic peaks assignable to; 29. 7ppm: -(CH₂) n-n>7, 14. 1ppm: CH3-CH2-CH2-, etc, can be observed. The relative intensities of these peaks suggest that the methylene chain included in asphalt is much longer (-(CH₂) _n) n>12 than that has been considered hitherto.Among the five asphalts of differrent crudes, the aromaticities of Taching asphalts are the lowest on all fractions. Mubarras asphalt contains large amount of saturate fraction. The aromaticities of the fractionated samples were, however, not significantly different from the other asphalts fractions. Among the other three, Arabian Light, Iranian Heavy, and Kuwait, no essential differences were observed.

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In order to elucidate the optimum conditions for the determination of nitrogen in coke, each of the semi-micro Kjeldahl, semi-micro gasification and automatic Duma's methods was investigated in some detail, and the following results were obtained.
(1) In the case of the semi-micro Kjeldahl method, the catalyst including selenium hastened remarkably the decomposition of coke in comparison with the catalyst excluding selenium, but the excessivey elongated heating after the termination of decompositions made the analytical results decreased. It was also recognized that the digestion time was affected by the degree of graphitization and particle size of the sample.
(2) In the case of semi-micro gasification method, although the procedure under the condition of the current JIS method gives preferable results, the precision of the analytical results was more improved by pulverizing the coke sample up to 74μm and adding soda lime in 20-25 times as much as the sample. This method has possessed so many merits in comparison with other methods as the good precision in the analytical results, the unnecessity of toxious reagents and the simplicity and rapidity in the procedure.
(3) In the case of automatic Duma's method, the reason why higher values in the analytical results were turned out in comparison with the former two methods was conjectured to be attributed to the generation of inert gases, and these bias could be improved considerably by pulverizing the samle to under 38μm, purging air at 100-300°C, and adjusting the combustion temperature to 1000-1100°C.
The reanalyses about the sample used in previous paper were carried out by adopting the improved conditions based on the above conclusions. The bias among the three types method mentioned above could be diminished until insignificant level.

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In order to develope a high speed-low temperature coal gasification process, the fundamental investigations on the effects of the metal (Fe, Co, Ni, Zn, Li) added over activated carbon and three kinds of coal chars and the component of gasifing gas mixture (H2O, H₂O-H₂ CO₂ CO₂-H₂, H₂, O₂, O₂-H₂O; balanced with N₂) on gasification rate and carbon selectivity converted to CO, CO₂, and CH₄ were carried out at 600° to 1000°C and atmospheric pressure by using thermobalance, gaschromatograph and X-ray diffractometer.
The main results obtained were as follows:
1) A trial approach with pure carbon (activated carbon prepared from PVDC-PVC copolymer resin by thermal decomposition in N₂) modified with metal addition by impregnation method was confirmed to be useful to evaluate the catalytic gasification activity of metal compounds contained originally in coal and/or added intentionally as catalyst.2) Mixing H₂ with gasifing gas of H₂O or CO₂ (mole ratio: H₂/H₂O or H₂/CO₂≥1) and addition of Fe (10%) to pure barbon or coal char promoted gasification rate and carbon selectivity to CO to produce a gas mixture which were rich in CO and H₂. This was supported by the fact that gasification rate of coal chars contained iron compounds originally was much faster than that of coal char in which iron compound was not containd. Li added only 0.5% increased gasification rate greatly, but almost of carbon was converted to CO₂ in any gasifing gases.
3) The content of ca. 10% Fe added was the most preferable amount for gasification pure carbon with H₂O-H₂ mixture. In the case of the mole ratio of H₂/H₂O less than ca.l, regardless of the amount of Fe added, the poor-graphitziable hard carbon was formed to decrease gasification rate and to stop gasification on its midcourse in an extreme case. And in these cases, since, the added Fe was always datected to be Fe₃O₄, Fe₃O₄ was supposed to promote formation of hard carbon.
4) Remarkable effects of Fe addition always accompanied the more reduced state of iron oxide, e.g., FeO or metallic Fe. Therefore, the basic mechaism of the catalytic gasification with metal M (Fe, CO, Ni) was composed, presumably, of the oxygen transfer cycle betwean the oxidation of M with H₂O (or CO₂) to from MO and H₂ (or CO) and the reduction fo Mo with carbon to give back to M and CO; the rate promotion by mixing H₂ with H₂O (or Co₂) was due to the cotribution of reduction of Mo with H₂ towards that of Mo with carbon.
5) Since iron is relatively cheap as catalyst and recoverable from gasified residue or ash, this iron catalyzed gasification process will be promising practically.

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