XRD measurements were carried out for 10 types of coal chars deashed with HCl and heat-treated at different temperatures. Among structural parameters estimated by STAC-XRD method, 'average number of aromatic layers in a stack' and 'stacking index' corresponded well to gasification parameters of chars prepared at 1500C. Such a good relationship was not found for champles prepared at the same temperature, but without acid treatment. Accordingly, gasification behavior of char can be numerically related to the stacking structure of aromatic layers under a deashed condition.

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In order to investigate the gasification mechanism, structure characterization of char is one of useful approaches. Solid state NMR measurements were performed for raw coals and chars obtained by a drop tube furnace (DTF) at 800, 1200, and 150℃. Demineralized chars treated by hydrochloric acid were also evaluated. Both of the chemical shift and the FWHM obtained by NMR spectra show good relationships with the size of carbon hexagonal network plane. Some structural differences were observed after demineralization because of a damage by strong acid.

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An attempt was made for obtaining UV/VIS absorption and fluorescence spectra of a whole Victorian brown coal and then examining the presence and abundance of poly-condensed aromatic ring systems (ARSs) in the coal. More than 99% of Loy Yang brown coal dissolved into aqueous NaOH solution at 473K. The absorption spectrum of the solubilized coal gives a direct indication of presence of ARSs with three to six condensed rings. Difference between the spectra of the solubilized coal and those of a tar sample from pyrolysis of the coal suggests that smaller ARSs are released as tar from the coal to preferentially to larger ARSs during the pyrolysis.

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Brown coals have a considerable amount of acidic functional groups of which the main component is carboxyl groups, and the acidity has a wide distribution, which can be changed by heat-treatment. The acidity distribution and its change by heat-treatment were analyzed by deconvolution of the acid-dissociation curve obtained by aqueous titration into several Gaussian type components. For Loy Yang brown coal from Australia dried at 50℃ under vacuum (LY50), the acid dissociation constant, K_a, was distributed over a wide pK_a range between 2 and 9. Then, the acidity distribution curve was divided into four component groups which were characterized by average pK_a values: average pK_a value of 3.8 (Group A), 5.2 (Group B), 6.8 (Group C), and 8.3 (Group D). Among them, Groups A, B, and C were assigned to carboxyl groups. From the changes of the amount of carboxyl groups when brown coal was heat-treated up to 400℃, it was found that the way of decrease was different among these acidic groups. The decrease of the amount of carboxyl groups was significant in Group C, and at 325℃ most of them disappeared. On the other hand, the carboxyl groups in Group A remained even at high temperature of 400℃.

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High temperature in-situ EPR studies has been carried out to investigate the change in paramagnetic species of coal up on heating. The spin concentration of coal during heating varied regardless of the thermoplastic properties of the coal. While, the peak-to-peak line width of EPR spectra closely correlated with the thremplasticity of coal, i.e. the line width of coking coal increased in the temperature range of thermoplasticity and decreased immediately in resolidification rage. The results indicate that the line width of EPR spectra could be a useful parameter to evaluate the thermoplastic and resolidification properties of coal.

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A new methodology for characterizing the thermal behavior of macromolecular network structure of coal has been developed by using the dielectric property measurement. It was found that the change of capacitance of solid coal demonstrated the characteristic pattern depending upon heating temperature, and from which the thermal property of polymeric substance such as glass transition, initial softening and fluid temperatures could be determined.

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Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) realizes accurate mass measurements due to ultrahigh resolution. When this MS is combined with electrospray ionization (ESI), known as a soft ionization method, molecular formulas of every constituent in a very complex mixture may be estimated directly without any pre-separation procedures. This MS was applied to solubilized products of coals after RICO reaction and gave complex spectra consisting of many peaks less than 400Da. Based on detected unsaturated dicarboxylic acids and saturated monocarboxylic acids, chemical structure of coal is discussed.

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Coal extracts with carbon disulfide (CS_2)/N-methyl-2-pyrrolidinone (NMP) mix solvent were analyzed by laser desorption (LD) and matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. MALDI method is good ionization method for large molecular weight compounds. But the coal extracts were complex mixtures, and matrices did not have enough effects for the mass spectrum. LD method had given good mass spectrum of coal extracts, and toluene solubles in extracts with CS_2/NMP were observed in selectively. LD and MALDI method provides protonated molecules and these method is good for analysis of large molecular weight compounds such as coal extracts.

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The surface tension of coal extract solution in N-methyl-2-pyrrolidinone were measured by Wilhelmy method. A discontinuity point corresponding to the critical micelle concentration was observed in the surface tension and logarithm concentration relationship. The non-linearly curved dependency of the surface tension on logarithm concentration could be explained by a simple association equilibrium qualitatively. The decrease in the dynamic suface tension was slow in coal extract solutions, taking over sevaral hours to an equilibrium value. The higher is the rate of decrease in surface tension, the higher is the concentration of the solution. The time profile could not be described in the theory of the diffusion-controlled process of adsorption to a surface. An kinetic mechanism of consecutive reaction was applied favourably to explain the time profile.

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Chemical structure analysis of Ash for coals using solid state NMR is very difficult because of quadrupolar interation. Recent MQMAS method using high magnetic fields is able to find new chemical sites of Al except of kaolin type, as quadrupolar interation is removed. MQMAS is very powerful and useful in order to clarify the chemical structure of ash for coals.

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We have a variety of classification conditions on coals, for example, the utility, the origin, the rank and so on. In this report, we fabricated a map, a birds-eye view from the standing point of a variety of spectroscopy (Infrared spectroscopy and others). We used a principal component analysis and made the map indicating the relation among colas all over the world, and classified them by the production nations using classification trees. As a result, we found that the splitting rules for identifying the production district of coals.

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The roles of mineral matter and intrinsic parameters of each coal in term of hydrogen transfer reaction with H_2 have been investigated using a tritium tracer technique Variations of the mineral matter content were achieved by removing gradually the mineral matter with HCl and HCl-HF treatment.

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Surface of Taiheiyo coal was observed by an atomic force microscope (AFM) equipped with an environment-controlled chamber. Surface properties and mechanical properties of coal under inert atmosphere were discussed. In coal surface, three components are recognized; a layered structure at several microns, unstructured and soft component, and fibrous component which gives a long range repulsive force Such unusual long range force is elucidated by comparing force curve of coal and thermally treated char.

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The effects of the reaction conditions on the hydrogenolysis reaction of cation (Co^<2+> or Ni^<2+>) exchanged Adaro coal in tetralin solvent with sulfur promoter were discussed. In comparison with the reactions of the demineralized coal with metalocene complex [(C_5H_5)_2Co,(C_5H_5)_2Ni] at 400℃-440℃, the conversion of acetone insoluble constituent in coal increased on those of cation exchanged coals. On the reaction of the demineralized coal with cation exchanged one, the upgrading of demineralized coal was also enhanced by the catalytic effect of cation in cation exchanged coal.

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Using tetralin solvent, the coprocessing of coal and three kinds of plastics, such as high-density polyethylene, polypropylene and polystyrene, gave only a little different oil yield from the individual reactions. On the other hand, the coprocessing using decalin solvent brought the increase of oil yield and the decrease of gas yield. Using decalin solvent, it was suggested the plastic radicals were stabilized by hydrogen derived from coal decomposition.

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Exploring the effective condition on the hydrogenolysis reaction of coal liquefaction residue (CLR) and waste tire, the additive effect of catalyst on the reaction of waste tire and demineralized CLR (PS) was discussed. On the reaction of PS and tire with MoO_3+S or Co_3O_4+S catalyst, the synergistic effects, such as the decease of n-hexane insoluble and the increase of n-hexane soluble, appeared due to the enhancement of the solvent effect of rubber in tire.

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We have been studying the development of resid upgrading process with an oil soluble catalyst. In this time, we report about our recent accomplishments as for our new catalyst and development of the process.

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A vacuum resid upgrading process has been developed with NiMo oil soluble catalyst. This report summarizes the recent accomplishment in the investigation to suppress sticky coke formation using some additives in the process.

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To suppress the emission of tar/soot from fluidized bed pyrolyzer, use of porous solids as bed material was proposed instead of non-porous sand. The carbon retention by the bed material was evaluated by use of a bench-scale fluidized bed reactor. Porous alumina particles were effective for carbon retention whereas non-porous sand was not. By feeding gas non-uniformly to enhance the solid internal circulation, the carbon retention by the porous bed material was increased.

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Kobe Steel has developed the slurry phase hydrocracking process (KOBELCO SPH process) for ultra heavy oils by applying its well-established brown coal liquefaction technology. In the present study, the applicability of the process to Canadian oilsand bitumen was examined. It was confirmed that high quality distillate could be obtained under relatively mild reaction conditions with high distillate yield more than 80wt% from autoclave tests.

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Gas oil fractions of different fossil fuels (middle east crude oil, oil sand bitumen and shale oil) were hydrotreated over NiMo/Al_2O_3 catalyst at 310 to 370℃, and the kinetics data of HDS, HDN and HY were obtained. The chemical compositions of the feedstocks were analyzed by using a capillary GC, equipped with several detectors (FID, SCD, NPD, MSD). The relation between the chemical composition and reactivities will be discussed.

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Dimethyl ether from natural gas or coal via syngas (3CO+3H_2→DME+CO_2) attracts much attention as high quality diesel fuel of next generation. Considering the compact process based on the small-scale carbon resources, low pressure-operation (at 1-3MPa) and high one-pass conversion (90% CO conversion) are required to produce DME with high efficiency. Temperature-gradient reactor (TGR) was effective to overcome both equilibrium limit of the reaction at high temperature and the low activity of catalyst at low temperature. The temperature gradient was optimized using simple genetic algorithm (GA) and neural network (NN). Evolution of the temperature profile was accelerated and successfully optimized to give 71% CO conversion higher than that in a conventional isothermal reactor (66%).

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Thermosetting resins are difficult to the chemical recycling through melt by heating or to the liquefaction by pyrolysis. Therefore most of them are either landfilled or incinerated now. In this study phenolic resins were subjected to liquid phase cracking and the effect of various solvent on the conversions and the oil yield was examined.

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In order to study the relationship between char structure and its gasification reactivity, model chars have been produced at 1000℃ from model coals which is prepared from cellulose at 200 to 350℃. Char carbon structure is influenced by pyrolysis temperature but not coal carbon structure. Char specific surface area is the controlling factor for char gasification reactivity.

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Coal chars produced in the three pyrolysis conditions were gasified with pure CO_2 at a temperature of 1173K and with air at 773K. Pore structures of the gasified chars were investigated by gas-adsorption methods, and then pore surface area and pore size distributions were calculated. The increase of CO_2 surface area in an initial stage of gasification appeared greater for the higher rank coal than for the lower. A significant enlargement of pore radius was found for the char produced at higher temperature. For the lower rank coal chars, the gasification rates were well correlated with the surface areas in a range around 0.4nm of pore radius.

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Three coal chars were gasified with carbon dioxide or steam using a Pressurized Drop Tube Furnace (PDTF) or thermogravimetry (TGA) at high temperature to simulate the inside of an air-blown two-stage entrained flow coal gasifier, and the kinetics of gasification reaction was analyzed up to 1500℃. Prepared chars, made by rapid pyrolysis of pulverized coals using a DTF, had about 40μm of average particle size. As a result, the gasification rate of each char was controlled by pore diffusion above about 1200℃ or 1300℃, and it was made clear that the gasification rate had a large difference between coal types at pore diffusion zone the same as at reaction control zone.

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In-situ reactivities of nascent chars from the rapid pyrolysis of Victorian brown coals were investigated at temperature and a steam partial pressure of 1173K and 53kPa, respectively, using a drop-tube/fixed-bed reactor. The nascent chars were gasified very quickly in the initial period at rates as high as 0.02s^<-1> on a char carbon basis. The rate of char gasification decreased as the conversion increased and then nearly terminated when the char conversion reached about 90%, leaving refractory material. In-situ gasification was also performed with nascent chars from the pyrolysis with a heating rate of 1K・s^<-1>. Comparing the results with those from the gasification of the rapid pyrolysis chars, it was revealed that the heating rate has no significant positive effect on the reactivity of nascent char with steam.

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Pyrolysis of five coals at high temperatures of ≧1000℃ has been studied with a fixed bed quartz or free fall graphite reactor to examine carbon structures in chars after devolatilization. The proportion of crystallized carbon with turbostratic structures increases irrespective of kind of coal, when pyrolysis temperature or solid residence time is raised from 1000 to1 350℃ or from 0 to 120sec, respectively. Highly dispersed CaO with the size of 20-50nm promotes transformation reactions of amorphous carbon to crystallized carbon. The reaction mechanism is discussed in term of interactions between CaO particles and char substrate.

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The possibility to produce activated carbon of high strength from coal without any binders was examined. To do so, oxidation treatment at 250 to 270℃ and hot briquetting below 500℃ and 10MPa were performed before carbonization and activation of bituminous coals. It was found that 1h of oxidation at 250℃ was enough to maximize the BET surface area, the crash strength and the packed density. For Peakdowns Highway, the BET surface area increased from 470 to 870m^2/g and the crash strength increased from 2 to 12MPa, by oxidation pretreatment.

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The customer of coal (ex. Power plant) limit the amount of fine coal in coal product on the ground that the fine coal (<2.4mm) causes fine particles pollution. It causes the lowering of the productivity. The double roll briquetting machine was selected for briquetting test to convert the fine coal to commercial commodity. As a result, it indicated that tapioca starch shows the best briquettability and it is possible to use an inexpensive by-product of tapioca as a binder.

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Influence of pressure upon the elemental balance of rapid pyrolysis of Taiheiyo coal was investigated. Relationship between carbon conversions to the whole gas, C_G, and to char showed that condensates was formed at the initial stage of pyrolysis and then it decomposed to gas and char. Oxygen and hydrogen conversions to the whole gas increased with C_G and attained around 100% and 80% at C_G≒26% respectively. Amount of CH_4 was in proportion to that of CO_2 and the relationship between shift reaction and CH_4 formation was presumed.

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For the entrained flow coal gasifier, char in the product gas deposit on the heat exchanger tube though the ash is in the state of solid phase, and the thermal inhibition is caused in the heat exchanger of the gasifier. It is understood that there are remarkably differences among the char kinds. Therefore, it is required to be predicted the influence which the char kind and the operation condition give to the heat transfer performance of heat exchanger in order to achieve the performance and the stable operation of IGCC. In this study, first of all, the particle size and the specific surface area of eight char which had been obtained by the 2T/d process development unit were measured, and the form change of char according to the progress of the reaction was clarified. And the char deposition tests around the horizontal circular tube were executed and char deposition mechanism was discussed.

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Coal, coa/CaO and coal/Ca(OH)_2 mixture were pyrolyzed under various pressure with heating rate 20K/min under various pressure. The total volume of gas product from pyrolysis was in the order of coal/Ca(OH)_2>coal/CaO >coal at high pressure. H_2 products in coal/CaO and coal/Ca(OH)_2 pyrolysis peaked in the temperature range of 923-973K. At this H_2 peak temperature, the H_2 content in product gas was approximately 80%, while there was little CO, CO_2, and CH_4. One reason for this is that the H_2O contained in coal can be brought to a higher temperature by the reactions of Ca(OH)_2 formation and decomposition. H_2O reacted with coal at high temperature, producing H_2 and CO. It was also found that CO can shift to CO_2, and that CO_2 can be fixed by CaO to CaCO_3 in the temperature range of the H_2 peak.

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Pyrolysis and gasification with steam of coal were examined at high temperatures up to 2700℃ using a tantalum-made reactor by 500W YAG laser heating. Yield of product gases of H_2, CO_2, CO and CH_4 decreased with temperature increase up to 2000℃. However, at 2700℃, those all yields were increased. Especially, increase of hydrogen yield was predominant. It was, therefore, suggested that there is an effect of direct pyrolysis of H_2O at high temperature more than 2000℃.

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Burning profiles in air obtained on a thermogravimetric analyzer (TGA) were used to study combustion behavior of residues produced in thermal and catalytic coal hydrogenation experiments. The characteristic combustion temperatures, T_<0.01>, T_<0.1>, T_<0.5>, T_<0.9> and T_p, were determined in the burning profiles and were used to represent the reactivity of these residues. Lower characteristic temperatures were found for the samples with higher H/C ratio and VM content. In particular, the effects of remained hydrogenation catalysts and enriched coal mineral matters on reactivity of residues were validated and discussed.

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