The proton NMR transmitter part of the nuclear magnetic double resonance apparatus previously reported (Nippon Kagaku Kaishi, 1979, 961) was improved in order to make the apparatus more stable and versatile. With this improved spectrometer, the ¹⁴N nuclear quadrupole resonances of pyrimidine derivatives of biological and pharmacological interests have been observed at room temperature,
( a ) 1, 2, 4-Triazine-3, 5(2 H, 4 H)-dione [6-azauracil]
( b ) 6-Methyl-1, 2, 4-triazine-3, 5( 2 H, 4 H)-dione [6-azathymine]
( c ) 5-Fluoro-2, 4(1 H, 3 H)-pyrimidinedione [5-fluorouracil]
( d ) 5-Fluoro-1-(tetrahydro-2-fury1)-2, 4(1 H, 3 H)-pyrimidinedione
The ¹⁴N coupling constant e²Qq/h (in kHz) and asymmetry parameter η are [2510, 0.51] for ( a ) ; [2450, 0.56] for ( b ) ; [3040, 0.36], [2680, 0.51] for ( c ) ; and [2680, 0.57] for ( d ). For the latter two compounds, ( c ) and ( d ), the observed lines were assigned to particular nitrogen sites in these molecules and electronic distribution on a nitrogen atom was calculated with the Towes and Dailey theory.

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An active Rh/TiO₂-VO₂ catalyst for the dealklylation was found in a study of catalytic activities of the Rh/VO2 catalytic systems. A Rh/TiO₂-VO₂ catalyst (Rh : 1 wt%, Ti/V =95/5 atomic ratio) prepared with TiO₂ as a support and with tris(acetylacetonato)rhodium (III) showed a high activity for the dealkylation at 450°C. This catalyst also showed a high activity for the steam reforming of heptane at low temperatures (450 and 500°C). Results of pulse reactions of CO with catalyst and of those of CH₄, with catalyst suggested that the water molecule adsorbed on the catalyst were transformed into hydrogen and surface oxygen. Measurements of electromotive force in the CO-catalyst system demonstrated that both the surface concentration and the oxidzing power of the surface oxygen were larger on the Rh/TiO₂-VO₂ catalyst than those of the surface oxygen on the original Rh/VO₂ catalyst.

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For acid catalyzed reactions, the catalytic activities of various metal ions supported on silica-alumina, silica gel and alumina (Me-SiO₂-Al₂O₃, Me-SiO₂, and Me-Al₂O₃; Me=Ag⁺, Cu²⁺, Cd²⁺, Co²⁺, and Ni²⁺) were enhanced by the pretreatment with hydrogen sulfide. An increase in the catalytic activities was dependent on the affinity of metal ions supported on the catalysts toward hydrogen sulfide. The IR spectra of the Me-SiO₂-Al₂O₃ catalyst treated with hydrogen sulfide indicated the formation of weak bonding between hydrogen sulfide and metal ions supported on Me-SiO₂-Al₂O₃. These data strongly suggested that an increase in catalytic activity of Me-SiO₂-Al₂O₃ by the pretreatment with hydrogen sulfide was attributed to reversibly adsorbed hydrogen sulfide molecules acting as Bronsted acid sites on metal ions supported on silica-alumina. For Me-SiO₂ and Me-Al₂O₃ catalysts, it was considered an increase in the catalytic activities by the pretreatment with hydrogen sulfide was attributed to the formation of new acid sites formed by hydrogen sulfide irreversibly adsorbed on metal ions supported on SiO₂ and Al₂O₃.

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Tin oxide film was deposited on a glass substrate by spraying the methanol solution of tin chloride including a small amount of antimony trichloride and heat treating it at 730°C.
One of the most reliable procedure to obtain stable tin oxide film with high electrical conductivity was as follow: The tin(IV) chloride solution having 2% antimony(III) chloride was sprayed from the delicate nozzle onto a glass substrate which was kept at 730°C in a temperature-controlled furnace. After cooling down to room temperature, the two steps of aging process were applied; heating at 30°C for 3 h and successive annealing at 165°C for 3 h. The resistivity of the specimen (20 mm x 10 mm x 10^-6mm) thus prepared ranged from 0.2 kΩ to 2 kΩ and the variation of its original value of the resistance was within ±5% after the lapse of ten years.

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To find out the best sample of tin oxide films for electronic apparatus, the following examinations were carried out: The temperature dependence of the electrical resistance of the films with and without load, the variation of their electrical resistance with temperature cycling, the moisture dependence of the electrical resistance, the electrical load test, reliability test and the secular changes of the electrical resistance after the lapse of seventeen years. Among the various samples, the tin oxide films containing 2% antimony and prepared in the temperature-controlled furnace at 730°C showed most successful characteristics. The film is proved to be stable enough for the use in electronic instruments.

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Kinetics of the substitution reactions of lanthanum(III), neodymiurm(III), samarium(III), gadolinium(III) and holmium(III) complexes of ethylenediaminetetraacetate(edta), N-(2-hydroxyethyl)ethylenediamine-N, N′, N′-triacetate(edtaoh) and 1, 2-cyclohexanediamine-N, N, N′, N′-tetraacetate(cydta) with lead(II) ions has been studied in the pH range of 2.38-5.97, at an ionic strength of 0.1, in the presence of excess metal ions over a temperature range of 15-30°C. The initial rate equations and activation parameters have been obtained from the measurement of change in absorbance in a region of 240-245 nm by stopped-flow method. Observed rate constants are in the order : La>Nd>Sm>Gd>Ho for the edta and cydta systems, and La>Nd≈Sm≈Gd≈Ho for the edtaoh system. The order of the effect of the ligands on the rate is edtaoh>edta>cydta for holmium and edta>edtaoh>cydta for the other metals. The rate constants for the formation of MHX^(n-4)- where M denotes the rare earth metal(III) and X^n- a completely deprotonated ligand anion, are in the order of La<Nd<Sm>Gd<Ho and are lower than those expected from the Eigen-Tamm mechanism.

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Lead isotope ratios of 29 archaeological glass samples (5 samples excavated in China, 10 samples excavated in Japan, and 14 samples made in Japan) were determined by surface ionization mass spectrometry with a HITACHI RMU-6 spectrometer. Of these glass samples, 28 were made of high lead glass, and one, of alkali-lime glass. Glass samples were decomposed in a mixture of hydrofluoric and nitric acids, and lead was separated from other elements by extraction with dithizone-chloroform. The lead nitrate solution thus prepared (corresponding to 0.5 μg Pb) was loaded on the rhenium single filament. The coefficients of variation of the determined ratios, ²⁰⁷Pb/²⁰⁶Pb and ²⁰⁸Pb/²⁰⁶Pb, were 0.1-0.3%.
Among the glasses excavated in Japan, some samples of the Yayoi period (ca. 3rd C. B. C. - ca. 3rd C. A. D.) contained a large amount of barium in addition to lead, and resembled closely Chinese pre-Han glasses not only in chemical compositions, but also in lead isotope ratios. This means that pre-Han glasses were brought to Japan and then re-cast into glass beads characteristic of Japan. The lead isotope ratios of the glasses were compared with those of Chinese (2 samples), Korean ( 2 ) and Japanese (17) galena orea, and it was found that 12 glass beads made in the 8th century at Nara and 2 fine glass tubes made at Saga in the 18th-19th centuries showed similar lead isotope ratios with those of the Japanese galena ores. Consequently it is considered that the Japanese galena ores were already used as one of raw materials at manufacturing of these glass beads in ancient centuries.

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Quaternary ammonium salts, amines and alkaloids are quantitatively extracted into organic solvents by forming respective ion pairs with a dye anion. These, however, interfere strongly with determination each other. For the enhancement of selectivity, various dye anions, such as 2, 6-dichlorophenolindophenol, picric acid and 2, 6-dibromophenolindophenol (DBIP) were examined against onium compounds. Of these dyes, DBIP was the most effective on the enhancement of sensitivity and selectivity in the determination of benzethonium. DBIP is a monoprotic acid, forming an ion-associate with benzethonium at pH5-10, which is effectively extracted into 1, 2-dichloroethane. Though other quaternary ammonium salts and amines were extractable at pH 8.2, their extractability was very poor at pH 5.6. Thus, only benzethonium could be determined spectrophotometrically at pH 5.6 without the disturbance of other quaternary ammonium salts and amines.
The extract had a maximum absorbance at 640 nm and the calibration curve obtained at pH 5.6 was linear over the range of (1 - 5) x 10^-6mol/l {0.448-2.24μg/ml} in aqueous solution with a good precision. The species was assumed to be [DBIPT]^-·[Benzethonium]⁺ from mole ratio method.

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The extraction equilibria of silico, phospho and arsenomolybdates into chloroform with methyl trioctyl ammonium chloride (R₃R′NCl : Capriquat) as a liquid anion exchanger were studied. The extracted species were estimated to be (R₃R′N)₄SiMo₁₂O₄₀, (R₃R′N)₃PMo₁₂O₄₀ and (R₃R′N)₃AsMo₁₂O₄₀. However, the latter two were observed to change to (R₃R′N)₂HPMo₁₂O₄₀ and (R₃R′N)₂HAsMo₁₂O₄₀ upon the increase in the acidity of the aqueous phase. The quantitative separation of silicon(IV) from phosphorus(V) could be performed by extracting the resulting silicomolybdate from hydrochloric acid (above 3 mol·dm^-3) with 0.5% Capriquat-chloroform solution. The above extraction was shown to be successfully applicable to the spectrophotometric determination of silicon (0.05 to 0.7%) in steel samples.

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The fluorescence behavior of diphenylmaleimides shows the following characteristic features; 1) the Stokes' shift correlates linearly with the solvent polarity parameter, E_T value, 2) the emission is quenched intramolecularly when the imido-nitrogen is attached to the atoms having n- or π-electrons, and 3) the quenching is observed in strongly acidic solutions. The photocyclization of the imides to yield phenanthrenes and 9, 10-dihydrophenanthrene-9, 10-dicarboximides is influenced by the dual effect of acids; when pH ca. 3, the yield of the dihydrophenanthrenes increases with the decrease in pH without the change in the reaction rate, whereas in more strongly acidic solutions, H₀, ca. +2, the photoreactivity is reduced in proportion to the fluorescence quenching. Discussion is given on the cyclization mechanism based on these observations.

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Irradiation of a solution of N-methyl-a-phenylmaleimide gave in almost quantitative yields three (2+2) dimers of trans-head-to-head, trans-head-to-tail, and cis-head-to-head types and only one (4+2) dimer, cis, transoid, cis-1-phenyl-1, 2, 3, 4-tetrahydronaphthalene-1, 2:3, 4-bis(N-methylcarboximide). The photodimer distribution was solvent-dependent; the yield of the (4+2) dimer increased with the increase in the solvent polarity. The (4+2) dimer was found to be formed on the prolonged heating of the maleimide. N-(p-Tolyl)-α-phenylmaleimide photodimerized similarly with lower efficiency. Discussion is made on the formation of the (4+2) dimer which may involve the intermediate formed through a photochemically forbidden (4s+2s) process. The photochemically as well as thermally induced reversion of the cyclobutane isomers to the starting material was also carried out.

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The polymers containing the 2-oxazolidinone ring in their main chains were synthesized by the polyaddition of p-bis(2-oxooxazolidin-5-ylmethoxy)benzene (PBOB) to diisocyanates by the use of N-methylpyrrolidone and triethylenediamine as solvent and catalyst, respectively. PBOB was prepared by the reaction between tris(2, 3-epoxypropyl)isocyanurate and hydroquinone in the presence of sodium hydroxide as a catalyst in refluxing solution of N, N-dimethylformamide. Three kinds of arylene and alkylene diisocyanates were used in the polyaddition reaction. The polymers, obtained in high yield, were generally soluble in m-cresol and N-methylpyrrolidone. The polymers had inherent viscosities in a range of 0.15-0.64 and gave transpareht films by solution casting. The polymer based upon PBOB and 4-methyl-m-phenylene diisocyanate gave the highest inherent viscosity. A confirmation that the base unit of the polymers contains the 2-oxazolidinone ring was obtained by the similiarity of the infrared spectra for five kinds of analogous monomeric 2-oxazolidinones, and by an elemental analysis. As well as the polymers anchoring the 2-oxazolidinone ring, the poly(2-oxazolidinones) obtained were found to form the complexes with phenol, iodine and bromine. Especially the amount of phenol in the complex increased with the increase in molecular weight of polymers.

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As a part of study to utilize waste plastic resins, the present study deals with the development of a new process to prepare a high quality activated carbon from PVC. To lower a reaction temperature and to raise an activated carbon yield Y(g(activated carbon)/g (PVC)), the study was carried out and discussed it by using the surface developing diagram, S_p(m²(activated carbon)/g(PVC)) [=Y×S_g(m²(activated carbon)/g(activated carbon))] vs. Y. Raw materials employed were PVC(powder), PVC(powder) containing metal chlorides (Cu, Fe : 0.1%) which were prepared from their ethanol solutions, and six kinds of industrial scrapped PVC which had once been shaped by pressing or extruding after blending with various organic and inorganic compounds to promote properties of a shaped PVC. Main results obtained are as follows:
1) Carbonization of PVC(powder) containing Cu in air or in HCl(5%)-air mixture marked by improved Y; Cl₂, formed from Deacon reaction (4HCl+O₂ → 2Cl₂+2H₂O) catalyzed by Cu, promotes dehydrochlorination and oxychlorination reactions.
2) Steam activation at ca. 800-900°C for 1-2h is preferable to that at a lower temperature than 700°C for a long time, irrespective of metal addition. The representative values of Y to prepare activated carbon with S_g=500-1000 m²/g are 15-25% for PVC containing 0.1% Cu and 10-18% for industrial scrapped PVC.
3) Adsorbed amount of I₂, UO₂²⁺ or PO₄^3- on activated carbon is proportional to each S_g, comparable to a commercial activated carbon prepared from coconut shell, and almost independent of raw PVC.

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The diazo-coupling reactions of benzenediazonium salt with several N, N-dialkylanilines have been investigated in nonaqueous solvents. The role of the solvent as a proton acceptor from the intermediate in the substitution reaction was demonstrated on the basis of base catalysis and hydrogen isotope effect. Neither significant base catalysis nor isotope effect was observed for the reaction in solvents of high basisity such as methanol and dimethyl sulfoxide. In a less basic solvent such as nitromethane, however, the reaction was strongly accelerated in the presence of base, i.e. pyridine, showing a considerable deuterium isotope effect. The dependence of base catalysis and isotope effect on the concentration of the substrate is also discussed.

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One g of Taiheiyo coal was treated with 8.8g of ethanol at 380-450°C for 45 min-5 h under 1-80 kg/cm2 of the nitrogen pressure in an autoclave. The solubility in, pyridine, benzene and ethanol increased remarkably with the nitrogen pressure, reaction temperature and reaction time. The nitrogen pressure may contribute to the increase in density of ethanol. The pyridine extraction yield was nearly 100% at 400°C and leveled off in 1 h. At 450°C the yield decreased again owing to the coking reaction.
The weight yield of the product was more than 100%. Since gases and water are evolved during the reaction, this value implies the addition of ethanol to coal, probably as alkyl groups. The conclusion is supported by the increase in the aliphatic IR absorptions and in the degree of substitution for aromatic nuclei ( σ ) or by the decrease of carbon aromaticity f_a. Molecular weight also decreases with the reaction time probably due to the splitting of the ether linkages.

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A new reaction for coal solubilization has been developed by applying alkylation reactions with olefin-containing hydrocarbon. For practical purposes, carcked light oils were used in the system as alkylative extraction reactants, which were supplied from the petroleum refineries. The present paper describes the results so far obtained under various experimental conditions such as coal nature, temperature, residence time and so on. Coal samples used were Taiheiyo coal (C 77.0%) and Yubari-shinko coal (C 86.6%). The catalytic cracking light oil (bp 300 to 441 K) employed contained 43 vol % of olefins and 13 vol % of aromatics. Without any catalyst, about a half of the fed coal became soluble in pyridine under the conditions of 623 K and 5.1 MPa within two hours (Fig. 3). In this case the coal solubilization was considered to occur by means of the supercritical extraction with the light oil, together with the thermal alkylation by the olefins, because the condition of the light oils became supercritical under the above temperature and pressure (Fig. 1). When p-toluenesulfonic acid was used as a solubilization catalyst, the coals were solubilized almost completely even under much more moderate conditions, for example, at 473 K and 1.9 MPa (Fig. 5). This suggests that the catalyst effectively promotes the alkylation reaction between coal and olefins in the oil. Occurrence of the alkylation reactions were confirmed by using α-olefin as a model reactant. It was found that the cracked light oils examined showed the most effective solubilization including the model reactant as alkylation reactant (Fig. 7). Average molecular weights of light oil soluble and pyridine soluble portions of products were determined by V. P. O. measurements, and were found to be about 400 and 1, 000, respectively.

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For the analysis of dissolution rate in coal liquefaction, continuous flow perfect-mixing-type reactor was used. The experiments were carried out by using Morwell brown coal at temperatures, 393-450°C under the pressure of 150 kg/cm²·G. And the equation of dissolution rate was introduced in consideration of the effects of hydrogen in equilibrium with coal slurry and of hydrogen donor ability of solvent. The over-all dissolution rate constant is expressed by the following equation:
k =(C_Coal0 - C_Coal) / C_Coal · (C_Hydrogen + A) · θ
where C_Coal0 and C_Coal are the concentrations of feed and of remaining coal after the reaction, respectively; C_Hydrogen is the concentration of hydrogen in equilibrium with coal slurry, A is the term of hydrogen donor ability of the solvent and θ( h ) is the residence time. All concentrations are expressed by maf coal %.
The temperature dependence of k for Morwell brown coal was expressed as in k=-14.7 x 10³(1/T) + 20.9, and activation energy of dissolution was 29.3 kcal/g-mol. In these experiments, the value A was 9.90, and it was found that the effect of A was considerably large in comparison with CHydrogen.

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A method of structural analysis of heavy oil derived from coal hydrogenation has been developed with the aid of a computer utilizing the analytical data of elementary analysis, ¹H- and ¹³C-NMR measurements, and molecular weight determination to construct their average molecular structure. A fundamental consideration for the proposed computer method is the selection of an appropriate combination of aliphatic and alicyclic structures substituted to aromatic rings. A list of various probable structures is prepared and stored in the computer memory. For a given molecular structure, the total number of carbons and the number of aromatic carbons would be a part of the input data. An combination of aliphatic groups is chosen by the computer such that the difference between the total number of molecular carbons and the number of aliphatic carbons will match the number of aromatic carbons. For bridge structures between two aromatic clusters in a molecule, a suitable binding structure among the structural arrangements filed in the computer memory is searched out. Thus, average chemical structures which have a set of values equivalent to the input experimental results can be derived by the present computer method.
Several reference materials as model compounds of the coal liquid heavy oil and aromatic fractions separated by liquid chromatography from the coal oil have been estimated by this method utilizing the theoretical and experimental input parameters. Agreement between proposed and estimated chemical structures is satisfactory for reference compounds, which are, however, accompanied by some different chemical structures consistent with the input data (Table 7). Results for unknown compounds from the coal liquid are reasonably close to the predicted chemical structure of the fractions which consist mainly of mono-, di-, and tri- and tetraaromatic ring compounds (Table 8).
Previously, only structural parameters can be obtained from this input data, while the present computer method provides with the average molecular structural formulae directly.

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The dissolution of coal in an anthracene oil, a creosote oil, and a single component of coal derived oil was attempted in order to investigate the dissolving property of various aromatic compounds (Table 2). It was indicated that coal conversion was conducted more efficiently in tricyclic compounds than in bicyclic compounds and remarkably enhanced by the addition of hydrogen-donor solvent (Table 4, Fig. 1). Addition of naphthol and quionline to tetralin resulted in a marked increase in the coal conversion probably because of the acceleration of cleavage of coal structure. Di- and octahydrophenanthrene were found to be superior to tetralin in the hydrogen-donating property (Table 4, 5). Moreover, the effect of solvent on the properties of Solvent Refined Coal was discussed and the properties of asphaltene and preasphaltene were compared with each other (Table 6, Fig. 2).

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Susceptibility of low rank coals to the extractive liquefaction, the extent of which was defined by the conversion of the coal into quinoline-soluble matter, was studied using a series of non-hydrogenative solvents at 370°C under atmospheric nitrogen in order to find the effective solvent and pretreatment to enhance their susceptibility to the economical process. The carbonization properties of the coals were also studied because the liquefaction and carbonization have common bases. Ashland A 240 petroleum pitch was found to be much superior to pyrene for the liquefaction of slightly fusible West-Kentucky(WK) No.14 which contained considerable sulfur and ashes, although both solvents were non-solvolytic.
Pretreatment of leaching in distilled water for 400 days, reffuxing with boiling water for 30 h, and washing with dilute mineral acid for 30 h were found to diminish significantly the sulfur and ash contents, markedly increasing the fluidity of the coal measured by Gieseler plastometry. Its fluidity was further enhanced by the presence of proper additive. Such pretreatment brought about a high liquefaction yield of the coal with pyrene over 90%, and improved remarkably its carbonization properties, which were defined by the free swelling index and the extent of anisotropic development, in the cocarbonization with the additive (10-20% addition). Fourier-transform infrared spectra revealed some notable changes in the absorption bands which may be ascribed to the phenoxyl or hydrogen-bonded carbonyl groups. Such changes may indicate the certain extent of depolymerization of coal molecules or removal of metal ions from the oxygen-containing groups. The mechanism and economy of slightly fusible coals in the liquefaction and carbonization are discussed from the views of adequate selection of the pretreatment and the solvent.

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The structural analysis of coal-derived oil by ¹³C-NMR method has been attempted. The aromatic region in the spectra of coal-derived oils can be divided into three groups, each being assignable to protonated, bridge head, and substituted carbons. The chemical shift ranges of these carbons are determined on the basis of the chemical shift data of model compounds and the characteristic ¹³C-NMR spectra of ring-type fractions (monocyclic, bicyclic, tri- and tetracyclic aromatics, and polycyclic aromatics and polar aromatics) of coal-derived oil.
The chemical shift ranges of these carbons are (115.0)-129.2 ppm for protonated carbon, 129.2-132.5 ppm for bridge head carbon, 132.5-(149.2) ppm for substituted carbon. Based on the concept of Brown-Ladner method, three structural parameters (f_a, H_au/C_a, σ) are defined by the following equations;
f_a=C_a/total carbon
H_au/C_a=(C_a-C_b)/C_a
σ=C_s/(C_a-C_b)
where C_a is the amout of aromatic carbon and C_b the amount of bridge head carbon and C_s the amount of substituted carbon. The structural parameters calculated by the above equations and the Brown-Ladner method were compared and discussed. The assignments of aliphatic carbons a to aromatic rings were made.

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Hydrogenation of Sohya coal (C 70.3%), Sumiyoshi coal (C 75.5%), Taiheiyo coal (C 76.7%) and Yubari coal (C 84.0%) under high pressure were carried out using a batch autoclave. The reaction product was fractionated by hexane and benzene. The structural parameters of each fraction were calculated from the ¹H-NMR spectra and the elemental analysis data by using the Brown-Ladner's equations. The reaction mechanism of the hydrogenation were discussed by following up the changes in the structural parameters of the reaction products in the course of reaction. The chemical reactions which are common to all coals were depolymerization (decomposition of the linking unit structures), dealkylation and hydrogenolsis of the aromatic rings. The hydrogenation reactivity of the aromatic ring in the structural unit is increased with the decrease of the number of aromatic rings in the structural unit and with the increase of oxygen in the structure.

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The most important factors for the conversion of the coal to liquid products are the hydrocracking of its aromatic structures, the cleavage of the weak bonds of coal and the stabilization of its intermediate radicals which lead to the effective depolymerization of coal. Through the authors studies on the hydrocracking of several types of polycyclic aromatic compounds, zinc chloride was revealed that it had relatively low activity for hydrogenation as compared with its high cracking ability.
Based on these imformation, binary eutectic salt of ZnCl₂ and other transition metal chloride which was expected to add hydrogenation ability to ZnCl₂, were used for the liquefaction of Yubari coal under the following conditions: contents of eutectic salt 5 wt% temperature 400°C, duration of reaction 3 h, hydrogen pressure 100 kg/cm². The binary mixture of ZnCl₂-CuCl(4 : 1), ZnCl₂-CrCl₃(4 : 1) and ZnCl₂-MoCl₅(4 : 1) eutectics showed better performance than ZnCl₂ from the standpoint of coal conversion to oil fraction (hexane-soluble portion) (Table 1). Especially, ZnCl₂-MoCl₅(4 : 1) eutectics was the best among the molten salts tested in the experiments in decreasing both gas and coke yield and increasing oil yield. In the hydrocracking of phenanthrene, the highest yield of monocyclic aromatic compounds was obtained by the equimolar mixture of ZnCl₂-MoCl₅(Table 2). Massive amounts of ZnCl₂-KCl-NaCl(3 : 1 : 1) ternary eutectics showed good catalytic effect in affording higher oil yield than that of ZnCl₂ for Yubari coal liquefaction under the reaction condition described above (Table 3).
Referring to physical properties of molten salt along with their intrinsic hydrocracking abilities, discussions were done on the role of such melts in coal liquefaction process. Binary melts, ZnCl₂-KCl(3 : 2) also showed its superiority over ZnCl₂ melts, in suppressing both gas and coke formation and increasing oil yield for the hydrocracking of SRC derived from Taiheiyo coal (Table 4).

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It was attempted to reduce the reaction time of the direct liquefaction of coal by using new disposable catalysts. First, the combination of iron(III) hydroxide and sulfur, which showed a remarkable activity in the coal liquefaction plant at Aoji on a industrial scale, was reinvestigated by using Minami-Oyubari coal. Increase of the amount of the catalyst resulted in increase of the coal conversion and the liquefaction yield. The activity of iron oxides as used together with sulfur differed considerably depending on the iron form. The coal conversion and oil fraction at 410°C are in the order (Fe(OH)₃+S)≥(Fe₃O4+S)≥(Fe₂O₃+S)>(FeO+S) and (FeO+S)>(Fe₃O₄+S)≥(Fe₂O₃+S)>(Fe(OH)₃+S), respectively. As disposable catalysts, the ores of iron, copper, zinc and lead were tested together with sulfur at 410°C by varying the reaction time. The combinations tested were found to be effective.
Next, the MBR ore (red iron)-sulfur combination was examined for the liquefaction of Miike coal. It showed a high activity and more than 90% coal conversion was obtained after about 10 min at 450°C. The oil products increased markedly with increasing amount of catalyst. It was found that the oil product was rich in light oil under bp 300°C.
On the basis of the present results, it was concluded that the reduction of reaction time is possible by using disposable catalysts and by improvement of the reactor.

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Reductive alkylation method proposed by Sternberg et al. was improved and the anion formation reaction of a coal with molten potassium metal was carried out in refluxing tetrahydrofuran without the presence of any electron transfer agents. The method was applied to the solubilization of Yubari coal (C 86%) by changing the reaction time of coal with molten potassium (0.5-24 h), the length of alkyl groups added (H-C₄H₉) and the ratio of potassium to coal (0.4-1.2 g/g). In the typical experiment, a butylated coal, prepared by the 2 h reaction with potassium-coal ratio of 0.4, contained 7 butyl groups per 100 original carbon atoms and the yields of pentane soluble part and benzene soluble-pentane insoluble part, estimated by Soxhlet extraction, were 18 and 57% respectively (Table 2). These values were comparable to those reported for the conventional procedures, The number of added butyl groups and the yields of soluble parts increased with the reaction time (Figs. 1 and 2) and with the potassium-coal ratio (Table 3). Solubility of 93% in hot benzene was achieved by the 6 h reaction with the ratio of 1.2 (Table 3). Structural parameters, estimated by the Brown-Ladner method, showed that twice as much as butyl groups were attached to the soluble parts of butylated Yubari coal compared with the solvent refined coal (Table 4). The average alkyl chain length attached to the coal roughly corresponded to that of added alkyl groups (Table 4). Contamination of the alkylated coal by tetrahydrofuran fragments seems not to cause any serious effect on the results, since naphthalene gives no alkylated products by the present procedures followed by hydrogenation with 2-propanol.

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Metallic catalyst being active for the methanation reaction of a synthetic gas are in general active for the direct hydrogenation of carbon to methane. It was found that the rate of formation of methane from catalyst-impregnated carbon decreased rapidly as the formation reaction proceeded (Fig. 1) In this paper, the formation of methane from cobalt-impregnated carbon was studied precisely. The rate of the formation of methane was prohibited by the deposition of carbon on active sites by the decomposition of methane or by Boudouard reaction. By removing the deposited carbon with hydrogen, the activity for the hydrogenation of bulk carbon was recovered (Fig. 7). The hydrogenation of cobalt-impregnated carbon on which ¹³C was deposited gave more than 85% of ¹³CH₄ at the initial stage in the recovery process (Figs. 8, 9).
These results strongly suggest that the diffusion of carbon to active sites is slow step in the hydrogenation of carbon, and that the mean free path of carbon until it arrives at the active sites which fulfill the structural prerequisites for hydrogenation of carbon depends on pressure of hydrogen. During the hydrogenation of carbon, accordingly, active sites have little carbon at the initial stage of the hydrogenation reaction, but are gradually covered by carbon as incresing the partial pressure of methane, which results in retarding the hydrogenation of bulk carbon.

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Two Japanese coals and a Chinese coal were treated with liquid ammonia. The behavior of the coal particles during the liquid ammonia treatment was visually observed. The microscopic observations of surfaces of the coals before and after ammonia treatment were also made. The grindability of the untreated and treated coal grains was investigated with a ball mill or a mortar grinder.
Results obtained are as follows; ( 1 ) Shin-Yubari coal was partially comminuted during the immersion of the coal in liquid ammonia and most of the coal particles were comminuted upon evaporation of liquid ammonia after the immersion treatment (Fig. 1). Taiheiyo coal was not comminuted during the immersion and even upon evaporation of the liquid ammonia. ( 2 ) The width of cracks in the coal particles formed by the ammonia treatment was larger in Taiheiyo coal than in Shin-Yubari coal (Fig. 2). ( 3 ) Microscopic observations of the treated Tatung coal showed the dependence of cracking behavior upon the maceral constituents (Fig. 3). ( 4 ) The compressive strength of the treated Shin-Yubari coal particles and of the treated Taiheiyo coal particles was reduced to one fourth and a half of that of the respective parent coal (Figs. 4, 5). ( 5 ) The size distribution of the coal particles was interpreted with the Rosin-Rammler equation. For Shin-Yubari coal, the liquid ammonia treatment gave the n value increased from 1.0 to 1.5, and the D_e value decreased from 560 to 100 μ after 30 min grinding (Fig. 8). ( 6 ) For Shin-Yubari coal, the energy required to grind up to 200 mesh size was reduced from 34 to 25 kWh/t by this treatment.

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Previous works, showed that nickel particles actively catalyzed the gasification of coal by steam, but unfortunately the catalytic reaction site was almost exclusively limited to the external surface of coal. In order to increase the contact area between coal and catalyst, we examined a new technique of catalyst, impregnation on coal, that is, an impregnation of nickel salt on coal during or after pulverization of coal (Shin-Yubari coal in this report).Nickel particles thus incorporated into coal were very fine and well dispersed (Figs. 1 and 2). The caking property of coal was destroyed to some extent (Table 1). A remarkable increase in gasification rate was observed as determined by a thermobalance. The ratio of the catalytic reaction rate to the uncatalyzed one varies with the amount`of catalyst and also with temperature : When 1.7% of nickel was added and steam gasification was carried out at 750°C, the ratio was 1.4 for the conventional catalyst impregnation method, whereas the ratio for the present method was 3.6. The ratio further increased to 5.7 when 7.5% of nickel was added by this method. The catalytic reaction rate with 7.5% nickel, and at 750°C corresponded to the uncatalyzed reaction rate at 850°C (Fig. 4). This indicates that the use of catalyst can lower the gasification temperature by about 100°C. The effect of particle size of coal was also examined. The better results were obtained with the finer coal particles (Table 3). As a conclusion, the coal-catalyst contact is demonstrated to be the most important factor in a catalytic coal gasification process.

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It has been attempted to lower the reaction temperature of the Boudouard reaction by utilizing molten salt of several metal carbonates as the reaction medium. A series of preliminary experiments indicated that carbonate salts (Li, Na, K and Ca were studied) react with carbonaceous. materials such as graphite or anthracite to produce carbon monoxide when heated to 700°C or more. The reaction does occur violating the thermodynamic prediction. It was also found that alkali metal carbonates degradates beyond expectation at the tenperature studied. The overall reaction can be expressed as M₂CO₃+C=M₂O+2CO. Effect of cationic species were observed and potassium salt showed the highest activity.
Direct conversion of carbon dioxide to carbon monoxide by the reaction with carbon particles, dispersed in a ternary mixture of molten carbonates, was also studied as a function of reaction temperature ranging from 650 to 750°C, the feed rate of CO2 and the bed volume of the melt. The CO production was linearly correlated with space velocity of CO2. The apparent activation energy of the reaction was 25 kcal/mol. At 750°C, the production of gas containing 60% carbon monoxide requires a space velocity of 30 h^-1.

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The promoting effects of alkali metal carbonates, i. e. Li2CO₃, Na2CO₃, K2CO₃, Rb2CO₃ and Cs2CO₃, on the reduction of carbon dioxide with carbon were investigated. The activity for the production of carbon monoxide was proportional to the amount of oxygen taken-up on the surface during the reaction, irrespective of the sort of alkali metal. From the measurements of carbon dioxide adsorption onto these doped carbons at lower temperatures, of thermal desorption of carbon carrying potassium carbonate labeled with carbon-13, and of X-ray photoelectron spectroscopy; the following mechanism was proposed;
M₂CO₃ =M₂O + CO₂
M₂O + C =2M + CO
2M + CO₂ =M₂O + CO
where M refers to alkali metals. The overall reaction (C+CO₂=2CO) proceeds through the redox cycle of alkali metal oxide formed by the decomposition of carbonate.

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A thermal plasma gasification of coal has an object to obtain useful gases such as acetylene and hydrogen from coal. In order to improve the contact efficiency of coal particles with plasma flame, a new 100 kW plasma gasifier was developed. This 100 kW apparatus has characteristics that the three separate torches, tilted so as to focus each other, form one big flame and that coal powder is introduced together with carrier gas into the center of this flame.
Using this apparatus, gasification of Taiheiyo coal (sub-bituminous coal) and Akabira coal (bituminous coal) in argon and argon-hydrogen plasmas was studied. The effects of moisture in coal, hydrogen concentration in plasma gas, and electric power were examined. Dried coal yielded more acetylene and less carbon monoxide and hydrogen. As the hydrogen concentration in plasma gas increased, acetylene yield also increased whereas carbon monoxide reached a constant value. As the electric power increased, acetylene and carbon monoxide yields per unit electric energy increased to reach maximum and then decreased. The highest acetylene yield per 1 kWh was 34 g/kWh, which is twice as much as our previous results. The carbon conversion to acetylene was 15% and the concentration of acetylene in the exit gases was 5.5% under the same conditions.
Contact efficiency and decomposition of acetylene were also discussed.

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In order to improve the "Hybrid Gasification Process" for the effective conversion of coal and residual oil slurry to clean fuel gas, experimental tests have been conducted in a benchscale pressurized fluidized bed gasifier with external electric heaters. In the thermal cracking zone, yields of gaseous hydrocarbons and carbon oxides increased with temperature and pressure, while that of by-product tar decreased with pressure. Gas compositions in the char partial oxidation zone were nearly equal to those in an equilibrium of the shift reaction.
On the basis of the experimental data, heat- and material-balances in the internally fired gasification have been investigated. Overall heat of reaction (endothermic) in the thermal cracking zone increased with temperature and decreased with pressure, showing that endothermic reactions such as thermal cracking and steam cracking were dominant at higher temperatures and exothermic hydrogasification took place at higher pressures. Product gas yields in the purely internally fired conditions were calculated under the simplified gasification model in which the heat required in the slurry thermal cracking zone could be supplied by the fluidized char and the partial oxidation gas from the char partial oxidation zone. Thermal efficiency (product gas heating value/raw materials heating value) was optimum at about 750-800°C in the thermal cracking zone, and increased as the pressure rose from 5 to 30 kg/cm²·G. Experimental results in the internally fired fluidized bed gasifier agreed with the calculated values.

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Pyrolysis of Iranian Heavy and Taching vacuum residues has been investigated with the intention to develop a process for producing olefins and a clean gas with high calorific value from vacuum residues. As shown in Fig. 1, the quartz reaction tube was constructed with two zones in which temperatures were controlled at about 450°C and 700-800°C, respectively. The vacuum residue, which was inserted into the low temperature zone in a platinum boat, was pyrolysed into cracked oil (M_W 300-400), which was carried to the high temperature zone by argon flow to undergo subsequent pyrolysis. The procedure is defined as two-stage pyrolysis. In comparison with the case when the boat was inserted into a high temperature zone directly, the yield of olefinic gas increased with the two-stage pyrolysis. Especially ethylene yield was increased by 1.5-1.8 times as shown in Runs 3 and 4 or Runs 12 and 14 as listed in Table 1 and 3. Consequently ethylene was obtained in a high yield of 15% from Iranian Heavy vacuum residue and of 26% from Taching vacuum residue. After fifteen to thirty minutes of pyrolysis of Iranian Heavy vacuum residue at 440°C, 20-30 wt% of feed oil was recovered as residues, which were mostly soluble in carbon disulfide. By raising the temperature at the low temperature zone to about 500°C, ethylene yield was decreased and most of the residue was carbonized. On the other hand, rate of decomposition was extremely slow at temperature below 430°C. Therefore, the optimum temperature of the low temperature zone was determined to be 440°C.

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Partial oxidation of residual oils with air and steam has been investigated using a fluidized bed of a nickel-dolomite catalyst for the purpose of produing fuel gas. When nickel is supported on dolomite which absorbs H₂S, the partial pressure of H₂S at gasification is kept at so low concentration that poisoning of the nickel active sites can be avoided. In the presence of the nickel-dolomite catalyst, partial oxidation by air converted residual oils mostly to carbon monoxide and hydrogen with minor production of methane or ethylene. The yield of product gas, however, increased by the addition of steam as a gasifing agent instead of air alone. The optimum ratio of steam to air was found when 25% of necessary oxygen atom were supplied from steam (Fig. 2). Arabian Light topped residue was gasified almost competely and the product gas composition was nearly at equilibrium at 900°C (Table 3). Simultaneously, 98% sulfur in the feed oil was absorbed by calcium oxide in the catalyst support (Fig. 3). By the addition of steam to air, durability of gasification activity and desulfurization ability of the catalyst was impoved from 20 to 25%, and 40 to 55% of calcium utilization, respectively (Figs. 5, 6). The reactivity of topped and vacuum other than Arabian Light topped residue was studied at various ratios of steam to air at 900°C. The reactivity decreased with increasing amount of Conradson Carbon Residue in the feed oil (Fig. 7). The general pattern in gasification and desulfurization showed no change with a change of the feed oil (Table 4, Fig. 8).

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Cracking of vacuum residual oil for production of low sulfur fuel oil has been carried out in the presence of iron ore particles in a fixed bed reactor. Steam was used as a diluent and the experimental conditions covered the temperature range 400-600°C.
The results indicated that the yields of the liquid and gaseous products were 80-90 and 2-7 wt%, respectively. The sulfur contents of the liquid product of lower gravity were 2-3 wt%. The value is considerably lower than those obtained by thermal cracking operations in the presence of mullite or sand particles. The distribution of total sulfur contained in the feed in the products was as follows: 30-55 wt% in the liquid product, 2-5 wt% in the gas, 15-25 wt% in the coke and 20-30 wt% in the iron ore. This suggests that the iron ore has a capability of capturing sulfur in the course of carcking of the residual oil.
The reactions of some iron oxides with hydrogen sulfide were investigated by use of a DTA equipment. The iron ore appeared to react with sulfur compounds in the reduced state of magnetite as well as of metallic iron to desulfurize the residual oil, since the desulfurization of the residual oil was obserbed at above 400°C at which temperature hydrogen is recognized in the gas produced by cracking of the oil. Iron ores are thus expected to be an effective solid medium for production of low sulfur fuel oil in the cracking process of residual oils.

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Studies have been made on cracking of residual oils over various ore catalysts to produce light distillates and hydrogen. A laterite catalyst was found to have the following interesting characteristics. (i) Cracking of residual oils over a laterite catalyst gives a higher coke yield than that over other catalysts (Table 3). (ii) When the coke deposited on the laterite catalyst is heated in a nitrogen stream, the gas containing carbon monoxide and carbon dioxide is generated, and at the time same iron oxides in the laterite catalyst are easily reduced (Table 4).
When laterite catalysts containing 1.22-8.75 wt% coke were heated at 950°C in a nitrogen stream, the degree of reduction of their iron oxide showed a linear relation to the level of coke deposited on the catalysts (Fig. 5). The amount of hydrogen generated by the steamiron reaction increased with increasing reduction of iron oxides, reaching a peak at about 50% reduction. Both reduction of iron oxide and heat generation for cracking of residual oils were simultaneously achived by partial oxidation of coke on a laterite catalyst. The degree of iron oxide reduction and the heat of reactions were controlled by regulating the ratio of oxygen to coke (Fig. 13).
A processing scheme for cracking of residual oils and generation of hydrogen has been proposed (Fig. 14).

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Khafji atmospheric residuum was hydrotreated over a NiO-MoO₃-Al₂O₃ catalyst to effect 82 and 48% removals of sulfur and nitrogen, respectively. Hydrocarbons and organic nitrogen compounds in the feed and the hydrotreated, product were characterized. After the hydrotreatment, the amount of asphaltenes was reduced by half, but its nitrogen content remained practically unchanged. The nitrogen content of maltenes in the hydrotreated product decreased to a half of that in the feed, whereas nitrogen in the light fractions greatly increased. Nitrogen type analyses by USBM-API 60 methods have revealed that the nitrogen compounds in the maltene of the feed mostly consist of pyrroles, amides, and pyridines and that the basic nitrogen compounds such as pyridines are easily removed by hydrotreatment. Pyrrole type nitrogen compounds were more refractory probably due to the adsorption of pyridines on the acidic catalyst surface in preference to pyrroles. When the contents in the produced distillate relative to those in the feed were compared, an increase in pyrrole type compounds and a great increase in basic nitrogen concentrations were observed. The trend should have resulted from hydrocracking of nitrogen compounds which were present in the maltene fraction of the feed. In contrast, amide compounds in the maltene were readily hydrocracked into hydrocarbons directly and thus without contamination of the distillate.

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Reaction features in catalytic conversion of asphaltenes in a petroleum heavy residue hydrotreating process (Asphaltenic Bottom Cracking Process) are described. A Khafji vacuum residue, a Boscan crude and an Athabasca bitumen containing high concentrations of asphaltenes were tested under the following conditions; temperature, 390-420°C; pressure, 140-180 kg/cm²·G; liquid hourly space velocity, 0.2-1.5 h^-1; hydrogen-to-oil volumetric ratio, 1000 Nl/l. The cylindrically (1/32 in diameter) extrudated catalyst was used.
Not only the general oil inspections of, but also a chemical structural analysis of the various feedstocks and product oils were made. The general oil inspections were made to determine the contents of asphaltenes, sulfur and metals in the samples as well as their gravities, viscosities and carbon residues. The chemical structures of the samples were studied with ¹H and ¹³C nuclear magnetic resonances (Tables 2, 4, 5, Figs. 2, 3, 10), gel permeation chromatography (Figs. 6, 8, 9, 12), and thin layer chromatography (Figs. 1, 7).
Effect of the chemical structures of the samples on the features and mechanisms of reactions taking place were discussed. A typical pattern in asphaltenes conversion proposed in this investigation suggests that the number of unit sheets decreases without change in structure of the umit sheets (Fig. 11) and that in the Boscan crude the dissociation mechanism of asphaltenes is related to the removal of vanadium.
The kinetics in the asphaltenes conversion was also discussed. The reaction rate in the conversion follows an apparent second order formula with respect to asphaltenes. It was found that gel permeation chromatography can be used to study the cracking of asphaltenic heavy residue.

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Hydrocracking of Cold Lake oil sand bitumen with the Co-Mo-Al₂O₃ powder catalyst has been carried out in a batch reactor (Fig. 1) at the hydrogen pressure of 70-200 kg/cm² in the temperature range from 375 to 435°C. The amount of the catalyst relative to that of bitumen was 0.03-0.1 by weight. The pressure was constant during the reaction by flowing hydrogen. The results on the decomposition of topped crude and of asphaltene, desulfurization and demetallation are shown in Fig. 2 and those on the production of gases in Fig. 3. Properties of products and of their topped crudes are shown in Tables 2 and 3. From these results it was found that desulfurization, denitrogenation and demetallation were accelerated with increasing temperature, hydrogen pressure and the amount of catalyst. With increasing temperature, the specific gravity, molecular weight, the amount of topped crude and of asphaltene, the H/C (by atomic ratio) and C_s/C_s^α, ratios of topped crude decreased, and aromaticity increased; both decomposition and carbonization of topped crude were accelerated. With increasing hydrogen pressure, molecular weight, the amount, and H/C an C_s/C_s^α ratios of topped crude increased (especially at high temperature), and theamount of asphaltene decreased. In this case decomposition was suppressed and hydrogenation was accelerated. The results obtained led to the conclusion that the main reaction in this hydrocracking was thermal decomposition. The decomposition of topped crude and the removal of vanadium and nickel were found to be expressed as pseudo first order reactions with respect to each reactant. On the other hand, the desulfurization was second order with respect to sulfur (Fig. 4 and 6). The apparent activation energies for decomposition, desulfurization and removal of vanadium and nickel were 37, 26, 22 and 29 kcal/mol, respectively (Fig. 5).

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Fluidized-bed pyrolysis of atactic polypropylene(APP), that is an unavoidable by-product in propylene polymerization, was tested for the purpose of oil recovery. APP fed into a sand fluidized bed was decomposed to gaseous and oil products by heat of partial oxidation. Since it is expected that the concentration of oxygen in the entering gas stream would considerably affect the yield and property of oil produced, experiments were carried out with varing gas composition. In case the oxygen concentration of inlet gas is high, the oxygen which remained unconsumed in the bed, allowed both the oxidation and the thermal decomposition of product oils to be conducted in the free board. This resulted in the enhanted production of lower molecular weight oils.

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The authors have already proposed a computer-aided search procedure for hydrogen production cycles based on the thermochemical decomposition principle. This procedure led to the formulation of three kinds of thermochemical cycles named UT-1, 2 and 3.
The last cycle consists of four reactions given by
CaBr₂ + H₂O → CaO + 2HBr ( 1 )
Ca0 + Br₂ → CaBr₂ + 1/20O₂ ( 2 )
Fe₃O₄ + 8HBr → 3FeBr₂ + 4H₂O + Br₂ ( 3 )
3FeBr₂ + 4H₂O → Fe₃O₄ + 6HBr + H₂ ( 4 )
At present, a series of experimental studies aiming at the industrialization of this process for H₂ production have been conducted. This paper is to describe the kinetic measurment of the reaction ( 3 ).
Magnetite powders mixed with silica sol were fabricated to a sphere of 10mm in diameter and the resultant sphere was calcined at 900°C in nitrogen stream. Hydrogen bromide gas was diluted with steam to the concentration range from 4.8 to 14.3 mol% for the expected concentration range in the industrialized process. Since the reaction was found to proceed topochemically, two kinetic expressions based on the core model were derived for lower (210-255°C) and higher (225-300°C) temperature ranges, respectively. It was found that the rate of the over-all reaction is controlled by the diffusion of reactants in the product layer and that the calculated effective diffusion coefficient within the layer is 7.23 x 10^-6cm²/s.

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High-temperature processes for desulfurization of low-Btu gases have been examined so that they may contribute considerably to the improvement of overall efficiency of power generation using combined cycle. By taking not only the capability of H₂S removal but also the high regenerability into account, the following reaction cycle is proposed.
BaCO₃ + H₂S → BaS + CO₂ + H₂O (900-1200°C)
BaS + CO₂ + H₂O → BaCO₃ + H₂S (80°C)
Both reactions were found to proceed well without forming any by-product. In comparison with CaO, BaCO₃, showed higher reactivity with lower concentration of H₂S and shorter time required for regeneration. The test for cyclic use based on the same sample suggested the high feasibility of the proposed reaction cycle.

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