Novel carbon-oxide composite-supported Ni, Co and Fe catalysts were prepared using PEG as a carbon source. It was found that Ni/C/Al₂O₃, Co/C/Al₂O₃ and Co/C/ZrO₂ catalyst were effective for steam reforming of ethanol. 16Co63C21Zr showed the highest activity and hydrogen yield among the Co catalysts. 32Ni47C21A exhibited 100% of ethanol conversion and 63% of hydrogen yield. Ni/C/Al₂O₃ system and Co/C/Al₂O₃ system showed the good performance of high activity and high hydrogen yield in steam reforming of ethanol in comparison with catalysts without using PEG.

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Zeolite (ZSM-5 with various SiO2/Al2O3 ratios)-alumina composite-supported PtNiMo sulfide catalysts were prepared, and were used to produce aromatics and hydrogen selectively by dehydrocyclization-cracking of soybean oil, a new type of reaction of fat under 1 MPa H2 in the range 420oC – 580oC. Although liquid products were not obtained using catalysts without Pt, soybean oil was completely cracked by Pt containing catalysts under 1 MPa H2 at above 420oC, producing gasoline with research octane number up to 92. The conversion decreased below 70% even at 500oC under 0.5 MPa H2 or using titania instead of alumina. When alumina support was modified by basic reagents in advance, larger amounts of CO and CO2 were formed in comparison with the catalysts, which included the unmodified alumina, in the reaction of soybean oil, indicating that decarbonylation and decarboxylation, which can inhibit the consumption of hydrogen, occurred preferentially.

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Currently, hydrogen has attracted much attention as a clean energy. It is known that TiO₂ has a photocatalytic activity, but is only active under the UV irradiation. On the other hand, Bi₂O₃ shows poor photocatalytic efficiency for the decomposition of organic pollutants due to a fast recombination of the photo-induced electron and hole pairs. To promote the photocatalytic performance of Bi₂O₃ by extending the response range to wider wavelength such as visible light or by promoting efficient separation of the photo-induced charge carriers, metal doping, the addition of metal particles has been explored. Bi₂O₃ is also known to have some crystalline phases such as α-phase (monoclinic), β-phase (tetragonal), γ-phase (cubic). Previously, we revealed that the photocatalytic activity β-phase is the most high among α-, β- and γ- phases¹⁾. In this study, TiO₂-Bi₂O₃ photocatalysts were prepared by the sol-gel method in order to examine the effects of the addition of TiO₂ to Bi₂O₃ on the photocatalytic decoloration of methylene blue by visible light irradiation. The addition of TiO₂ changed crystalline phase of Bi₂O₃. The addition of Pt inhibited recombination between electrons and holes, and promoted the photocatalytic activity.

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This paper reports a numerical simulation of coal devolatilization behavior. The new Extended-CPD Model which can predict the composition of light gas and tar volatilized by coal particles is introduced into the simulation and coupled with a detailed gaseous phase chemistry. DTF experiments in CRIEPI is targeted. N₂=100% and a N₂/O₂=99.5%/0.5%, totally 2 conditions are performed. Results show that in 2 conditions the behavior of PAHs are quite different. It is confirmed that the numerical method used in this paper can capture the C, H, O composition in particles, also the PAH concentration and reacting rate distribution in gas phase qualitatively.

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In this study, relation between coal property and mercury release behavior from coals during mild pyrolysis are examined. In addition, the inference of coal properties on the analysis of Hg content in the coal char and coal ash during coal pyrolysis and combustion are examined. When various kinds of coal were subjected to mild pyrolysis and combustion, the relative standard deviation values for Hg content in coal char and ash decreed compare to the results from original coals. Also, the factors affecting the Hg release in the mild pyrolysis are examined and the inference of volatile component in coals on the Hg release behavior from coals during mild pyrolysis is discussed.

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We have been studying the cokemaking properties of A-SCC (Advanced Substitute Coking Coal) produced by thermal-hydrogenation processing of brown coal. After we refined the reforming conditions using a small autoclave, A-SCC derived from low ash brown coal was produced by auto-claves with capacity of 1.6L. The samples of A-SCC were analyzed to evaluate the performance as a coking additive. They were mixed with the test blend of coal consisting of 10% of poor coking coal and 90% of the standard blend of coal used for blast furnace coke production in Japan. The several samples of coke were produced with a simulated coke oven, a small-scale test facility. The strengths of coke were measured with several ratios of addition of A-SCC.

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This study aim to investigate the effects of HPC, High Performance Coking additive, addition on the thermoplasticity and re-solidification of non- or slightly-coking coals by means of in-situ high temperature ¹H-NMR relaxation measurement and in-situ high temperature ESR spectrometer. Thermoplastic phenomena of coals are evaluated both qualitatively and quantitatively by the variation of mobile, Hm, components. Synergistic effects of coal with HPC is determined quantitatively as a change in the amount of mobile components, IHm, with temperature. The ESR spectra of HPC added coal indicate the development of poly-aromatic structure at re-solidification temperature. The enhancement of coke strength with HPC can be attributable to the quantitative and qualitative improvement of mobile component at the re-solidification temperature range, result in a development of poly-aromatic structure. It is confirmed that the ¹H-NMR relaxation measurement and in-situ high temperature ESR spectrometer is the appropriate dynamic measurement technique to characterize the thermoplastic properties of coal.

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It is known that coal is oxidized slowly and gives heat off from low-temperature. In this report, caking coal was oxidized by air at 80°C for 1day as sample, and then, the oxidized coal was investigated its structural change by various analyses (industrial analysis, elemental analysis, XRD, Raman scattering spectroscopy, IR, Solid-state¹³C NMR and Solid-state¹H NMR). When the coal is oxidized by air at 80°C for 1day, the temperature of coal bed is increased. The results indicate oxidation of coal was occurred. This oxidized sample was analyzed. As a result, fine difference of chemical structure was caught by IR, Solid-stete¹³C NMR and Solid-state¹H NMR.

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Japanese steel industries, which are importing all coal resources required, are facing the necessity of increasing usable coal resources due to the recent rapid decrease of high-grade coking coal reserve and increase of its price. Low rank coals such as brown coals and subbituminous coals are promising substitutes for coking coals since they are abundant and cost-effective. However, the low rank coals generally have no thermoplasticity which is required for producing a coke with high mechanical strength using conventional coke ovens. In this work we have proposed to pretreat low rank coals with aqueous oxidant such as hydrogen peroxide in order to convert them into thermoplastic coals suitable for coke making by oxidative degradation reactions. An Australian brown coal was treated with hydrogen peroxide aqueous solution either at room temperature for 4, 8 and 24 h, or at 60°C for 0.5, 1 and 2 h. The treated coals were then pelletized at room temperature and carbonized at 900°C to obtain cokes. It was found that the strength of the resulting cokes increased with increasing the oxidation time at 60°C and reached the level of a commercial coke, indicating that the treatment gave thermoplasticity to the coal. It was thus suggested that the wet oxidation was effective as a pretreatment for producing cokes from low rank coals.

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Low rank coals are susceptible to spontaneous combustion, but they must be heated over a critical temperature of around 70 to 80 °C before spontaneous combustion starts. This work focused on the adsorption of water vapor as a possible mechanism of the temperature increase up to the critical temperature and rapid temperature increase over 100 °C. Accurate measurement of heat generation rates was undertaken by use of TG, DSC, and TG-DSC in both dry and humid atmospheres at 30 to 150 °C. The direct measurement of temperature increase of coal particles through the adsorption of water vapor was also made at saturated airs ranging from 30 to 96 °C.

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Pyrolysis with a rapid heating rate can be expected to achieve a higher yield of volatile matter than that with a slow heating rate. Therefore, this technique is attracting attention as a means to obtain useful liquid or gaseous materials in high yields. This study quantitatively investigated the effects of heat rate and coal type on the yield of useful tar components using GC-MS. The main outcomes of the study are as follows: (1) The yields of cyclized aromatic hydrocarbons such as benzene, styrene, indene, naphthalene, and PAH increased with increasing heating rate. (2) The yield of indene, which can be used as a functional raw material, increased proportionally with increasing H/C ratio. The yield of fluorene, which can be used to enhance resin functionality, increased only for coals with a high H/C ratio.

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Asphaltene in Canadian oil sand bitumen was separated to five fractions by liquid chromatography using acidic/basic alumina columns, and all the fractions were analyzed by CHNS, TG, GPC, FTIR, and NMR to examine their properties. The results indicated that the asphaltene contained about 5% of fraction with peculiar properties: strong adsorption of methanol, infusible at high temperatures, insoluble to organic solvents (such as toluene and dichloromethane) after removal of eluent, high oxygen content, high aromaticity, and high aggregability.

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Two novel methods were studied to determine aliphatic carbonyl group using infrared (IR) spectroscopy. Number of carbonyl can be estimated from the number of CH, CH₂, CH₃ using carbonyl / (CH + CH₂ + CH₃) IR area ratio in method 1, and be estimated using IR area ratio of carbonyl to peak of solvent, such as bromoform and DMSO-d₆ in method 2.

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Petroleomics is a new scientific paradigm in which petroleum is analyzed, modeled, and treated in molecular level. An informatics system was developed to obtain the chemical structure, physical properties, and reactivity of petroleum molecules, and also to evaluate their usefulness in the oil industry. The system, called the "petro-informatics platform: PIP," integrated three fundamental technologies of petroleomics, namely, detailed composition and structure analysis, molecule-based kinetic modeling, and petro-informatics.

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For accelerating asphaltene evaluation, a commercial packaged apparatus applying laser light scattering technique was used. This apparatus is useful for evaluating asphaltene onset pressure (AOP) and count/size of precipitated asphaltene particles. During isothermal de-pressurizing test, AOP is detected by mainly using solid detection system (SDS) equipped in the apparatus. The SDS consists of laser light source, receiver, and glass cell. SDS-measurement provides continuous profile by Near infrared Laser Scattering (NIR-LS) that can typically show a sudden drop when asphaltene particles start precipitating. However, our laboratory experience is sometimes faced to untypical NIR-LS profiles. This paper focused on a case that did not detect SDS-basis AOP for a single phased fluid from domestic oil field. To find a way for solution, it was applied to estimate AOP by comprehensively interpreting whole data (i.e. particle count/size, density and viscosity) simultaneously taken by the SDS. As a result, alternative AOP was estimated successfully.

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We developed a digital oil model (a full molecular model of crude oil) for a crude oil sample, of which the field actually confronts asphaltene problems, on the basis of analytical experiments and quantitative molecular representation (QMR) method. After constructing the digital oil model, we calculated association energies of asphaltenes in various solvents by potential of mean force (PMF) using molecular dynamics simulations, which are, in turn, used for selecting better asphaltene solvents. Finally, we show that "digital oil" conception will exhibit its importance in the petroleum industry, including coal, tar, and shale gas systems, which are quite difficult to approach by experimental method.

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Deeper understanding of chemistry and kinetics included in the thermochemical conversions of biomass resources can be encouraged towards their novel and efficient utilizations. A brief review is provided on recent developments and future perspectives in kinetic modeling of thermochemical conversion of biomass at mechanistic level. Topics include identifying decisive mechanism of cellulose primary depolymerization upon heating, and vapor phase cracking of volatiles derived from fast pyrolysis.

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Coal tar is utilized for chemicals and carbon materials using the separation, purification and carbonization technique. It is required to separation and clacking of the heaviest fraction includes the quinoline insoluble, removal of sulfur and nitrogen for the product quality improvement. We are hoping for the solution of such problems for the coal tar industry by activities of the hydrocarbonomics section.

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