The Fluidized bed combustion (FBC) is expected to be one of promising economical combustion techniques for coal. However, the FBC technique is requied to be so developed that NO emission can be reduced extensively, because coal generally contains a greater amount of introgen compounds than petroleum fuels.
At first, this paper introduces some characteristic experimental results on the NO emissions of fluidized bed coal combustion processes. Then, it presents a brief discussion on the mechanisms of both NO formation and control in the fluidized bed. Finally, it suggests some problems in developing practical fluidized bed furnaces with low NO emissions.

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In order to develop the one step direct reduction process of iron ores and contribute to the save energy of iron manufacturing industry, the fundamental investigations on the reducing gas (CH₄, CH₃OH, CH₄-H₂O mixture) and the effects of catalyst (Ni, Co) added and Al₂O₃ contained. etc. were carried out.
The iron ores employed were three kinds of hematites and two kinds of magnetites. Furthermore, Fe₂O₃, Fe₂O₃-Al₂O₃ to clearify the effect of impurities in natural ores, and NiO, Co₃O₄ to clearify the catalytic effects of Ni and Co added were employed. These metal oxides were prepared by the precipitation from the nitrates with NH₃ aq.
The reduction experiments were carried out by using a thermobalance and a packed bed reactor under atmospheric pressure and at 300-950°C. The average diameters of the granular samples were 0.25 mm for the thermobalance and 0.50 mm for the packed bed reactor. On the other hand, the gases formed were determined by gaschromatograph, and the chemical changes before and after reaction of solid samples were analyzed by X-ray diffraction. Inlet gas concentrations were 3-50%, CH₄-0-6%H₂O-N₂, 4%CH₃OH-N₂, 4%CO-8%H₂-N₂, 12%H₂-N, and 12%CO-N₂, and the total gas flow rate was 650 Ncm³/min toward ca. 350 mg as iron component.
The main results and informations were as follows:
(1) In the reduction of ores with CH₄, the Al₂O₃ component in or ecatalyzed the decomposition of CH₄ to H₂ and carbon under the state of wiistite (Fe_1-xO). The reduction rate was promoted above ca. 850°C. However, the catalytic activity of a small amount (1-2%) of Ni or Co was sufficient to promote the reduction with the fairly reasonable rate at ca. 700°C. Also, a small of sulfur added was very effective to restrain the carbon deposit, but poisoned the activity of catalyst.
(2) In the reduction of ores with CH₃OH above 800°C, CH₃OH decomposed rapidly to H₂ and CO, and these gases reduced the ores to Fe without any side reactions. Also, Ni was effective to promote the reduction.
(3) In generally, the reduction rate of magnetite was much lower than that of hematite with any reducing gas, but the reactivity of magnetite ores was increased by oxidation to hematite with air prior to the reduction.
(4) In the reduction of ores with CH₄-H₂O mixure, Ni acted as a reforming catalyst to H₂ and CO (mainly H₂), and the selection of the operation conditions such as the ratio of CH₄/H₂O, the reaction temperature and space velocity was very important.

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Extractive chemical disintegration of various coals (C: 74-92%) in creosote oil has been studied at the reaction temperature of 420°C, the hydrogen initial pressure of 30kg/cm² and the reaction time of 30min., using 500 ml batch type autoclave.
According to the analytical results of its chemical structure, the difference in the chemical structure of the extract from the different coals, and correlation of the original coal and the properties of the extracts were discussed.
The conversion of 95%-24% were obtained, and show a general increase with the increase of H/C ratio, o/C ratio, volatile matter content and reactive macerals content of original coals.
Calorific value, ash content and softening temperature of the extracts were 9000 kcal/ kg, -0.3% and 130-350°C respectively.
A definite correlation between softening temperature and the molecular weight of the extract was found and other correlation of the properties of the extracts and original coals were discussed.
Extracts prepared from different coals have a comparatively similar elementary com-position. However, it was considered that the aromatic ring structure of extracts inherited the characteristic chemical structures of each original coal.

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The catalytic co-methanation of CO and CO₂ was studied with the objective of utilizing not only CO but also CO₂ to synthesize a clean and highcalorific gaseous fuel, methane.
Simultaneous methanation of CO and CO₂ at low temperature was achieved by using the novel composite-catalyst such as 5%Ni-27%La₂O₃-0.6%Ru supported on the spherical silica support (0.3mm) having micro (5nm) and macro (600nm) bimodal pore structures. The reaction-gas mixture containing considerably high concentration of CO (0.06 atm) and CO₂ (0.6 atm) with excess hydrogen (0.88 atm) was flowed at a space velocity of 11400 hr^-1 in the temperature range from 170 to 290°C at atmospheric pressure. With the rise in reaction temperature, the reaction rate of CO₂ increased acceleratedly of ter almost comlete consumption of CO, and total conversion of both CO and CO₂ into methane with 100% selectivity and a high space time yield (61 mol/liter ·hr) were observed at 270°C.
On the basis of kinetic data, the cause of the accelerating effect was determined that the concentration of surfece-carbon spices, which accompanies with CO methanation and has strong retardative action for the reaction, reduced in a marked degree at higher CO conversion, and released the retardation.

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Yubarishinko coal was hydrogenated with Adkins catalyst, and the prod-uct was extracted with hexane in a soxhiet extractor. The oil was separated into neutral oil, acidic oil and basic oil. The neutral oil was further fractionated into saturated hydro-carbons (Fr-P), monoaromatic (Fr-M), diaromatic (Fr-D), three or more aromatic rings (Fr-T) and polyaromatic-polar hydrocarbons (Fr-PP) by means of dual-packed liquid chromatography developed according to API-project 60 method.
Both acidic and basic oil were subjected to analysis by combined high resolution mass spectrometry and low voltage low resolution mass spectrometry. The acidic oil was mainly composed of mono aromatic ring hydrocarbons with alkyl side chains of about two carbon atoms and a hydroxyl group.The major compound types of the basic oil were the mass Z series rom-11N to-21N compounds with three or four alkyl carbons. GC/MS analysis of Fr-P indicated that n-paraffins were major constituents and a little mono cyclic saturated hydrocarbons with a straight chain existed. For aromatic fraction (Fr-M, Fr-D and Fr-T), compounds in each mass Z series were eluted from-8 series to-32 series nearly in order. Mass Z series, -12, -14, and -16, were major constituents. Fr-PP included too many com-pounds to be evaluated by mass spectrometry.

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Zinc-dust distillation has been used for elucidating the basic skeleton of organic compound having oxygen contaning groups such as hydroxyl, carboxyl and carbonyl gruop.
In order to determine aromatic skeletons in chemical structure of peat humic acid, zinc-dust distillation was carried out at 500°C for 2 hr in a stream of hydrogen in compari-son with the results from model substances such as δ-lactone, phthalic acid, cumarin and 1, 2-naphthoquinone.
Identification and semi-quantitative determination of polycyclic aromatic hydrocarbons in the reduction products from zinc-dust distillation were performed by using the gas chromatography and GC-MS techniques.
The total yield of polycyclic hydrocarbons in the reduction products having anthracene, pyrene and perylene ring was 1.9 per cent based on the original peat humic acid. However, the yield of aromatic hydrocarbons containing 3 to 5 rings from peat humic acid was approx-imately equal to those from other model substances.
From these results, it assumed that the peat humic acid has no polycyclic ring systems as the aromatic structure, and that the polycyclic aromatic hydrocarbons obtained from the peat humic acid by zinc-dust distillation was formed by rearrangement and condensation of oxygen containing structure under reaction conditions.

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In order to confirm whether in the study of structural analysis a previous fractionation in term of chemical functionality is necessary or not, a gelchromatographical fractionation was carried out on the methanol-soluble portions of the benzene, acetone soluble portions of ten n-hexane insoluble parts of pyridine extracts from Sorachi coal.
A spectroscopic study was carried out on the fractions separated by Sephadex-LH 20 column. The combination of spectroscopic analysis with structural analysis leads to the conctusion as follows:
(i) The gelchromatographic fractionation by Sephadex LH-20 is a better method to separate the SBM-portions in term of difficult chemical functionality. It is found to be performed according to molecular weight, the content of oxygen and aliphatic structure.
(ii) All fractions show nearly equal extinction coefficient in their UV-spectra. The value suggests the existence of aromatic compounds composed of two or three rings.
(iii) In the study of structural analysis, the number of aromatic ring and aromatic carbon per unit structures war easily obtained from Figure 4 by assuming that the aromatic structure of unit structure is composed of unsubstituted polynuclear aromatic compounds and by falling them into the seven groups of aromatic ring arrangements.
(iv) Structural analysis suggests that each fractions is composed of similar aromatic structure with two or three rings and that the basic structure may polimerize in degree of one unit or three unit.
(v) The portion obtined by multiplied fractional extraction may contain similar basic structure.

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In order to clarify the chemical structure of the methanol insoluble po-rtions (the RBM-portions) of acetonebenzene soluble portions of n-hexane extracted residues obtained from pyridine extracts from Sorachi coal, a spectroscopic and structural analysis was applied not to extracts themselves but to the fraction gelchromatographically separated in term of different chemical functionality.
The gelchromatographic separation of the methanol-insoluble portions, the RBM-portions, of the acetone-benzene soluble portions of the n-hexane insoluble parts of pyridine extracts from Sorachi coal, gives eleven fractions (F-1-F-11) accoding to the molecular weight, the content of oxygen and the length or number of aliphatic structure.
The combination of characteristics of gelchromatographic fractionation by Sephadex LH-20 with additional study by physical methods, elemental analysis, etc, leads to the conclusions as follows:
(i) All fractions have nearly equal extinction coefficient in their UV-spectra, the values of which may correspond to the ones of polynuclear aromatic compounds composed of three or five rings.
(ii) Structural analysis indicate that all fractions have three or five aromatic rings per structure unit with the aliphatic structure. But though the arrangment of aromatic rings is not clear, the combination of informations from the structural analysis with the results of UV-spectra leads to that the type of ring arrangement belongs to 1-type or 4-type or 5-type in Figure 4.
(iii) The aromatic structure of structural unit in the RBM-portions is similar one another, but the degree of polimerization is various, namely, 2 or 5.

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Three crystalline substances were isolated from the SBM-portion of the extracted residues from pyridine extracts of Sorachi coal with n-hexane. They were characterized by using the IR-, UV-, NMR-and Mass-spectra together with their elementary analysis. Two of them are not clearly denoted in the term of structural formula, but the one seems to be comprised of either alicyclicring or methyl substituted cata-condensed five aromatic rings and the other is composed of ether linkage and two or three condensed aromatic rings. The last one seems to be a mixture of di-and tri-methyl 1, 2, 5, 6-dibenzanthracene.
All the compounds separated belong to the aromatic class and reveal the fundamental units of coal structure. The presence of either methylene bridge or alicyclic methylene structurer in the compound (A) is compatible with the coal model put forward by P.H. Given and the model polymers used by P.M.J. Wolfs et al. Though there is still many controversies regarding oxygen groups in coal, the Compound (B) suggests that a kind of oxygen groups is present as ether and or heterocyclic oxygen groups. This is a good aggre-ment with the work stated by M.M. Roy and the new compound found by K. Ouchi et al.

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