Heterogeneous catalysis in supercritical water oxidation (SCWO) is a new approach to improve the reaction efficiency of the treatment of hazardous waste water. In this study, the kinetic analysis of catalytic SCWO of coke works waste with manganese oxide (MnO₂) was performed to obtain fundamental data for the reactor design, as well as information about interactions affecting the reaction rate between the reaction species. The major component of the coke works waste is NH₃. Catalytic SCWO of NH₃ solution confirmed that MnO₂ is a good catalyst for the complete oxidation of NH₃. SCWO of an aqueous mixture of phenol and NH₃ was examined as a model solution of the real waste. The oxidation rate of NH₃ in the model solution was lower than that of an aqueous solution of NH₃. The presence of NH₃ in the model solution did not affect the phenol conversion, but strongly suppressed the decomposition of total organic carbon (TOC). These inhibition effects between NH₃ and phenol are explainable by a Langmuir-type model, in which all corresponding species are assumed to adsorb competitively on the same catalytic site. Catalytic SCWO of diluted real waste showed a similar inhibition effect especially with shorter contact times of less than 0.5s. However, very high conversions of both NH₃ and TOC were achieved within 2s of contact time at 500°C. These experimental results suggest that catalytic SCWO is a promising technique for the complete decomposition of coke works waste.

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The reaction scheme of the aromatization of C₆ hydrocarbons catalyzed by platinum supported on zeolite L (Pt/KL) was investigated using n-hexane, methylcyclopentane and 3-methylpentane as reactants. The aromatization proceeded through a similar scheme to that using conventional non-acidic reforming catalysts. Skeletal isomerization of hexanes proceeded via methylcyclopentane and benzene was formed through the closure of the 1, 6-carbon ring from n-hexane.
Based on the experimental results, a kinetic model and rate equations for the reactions of C₆ hydrocarbons over Pt/KL were proposed. The kinetic constants for the n-hexane reactions at 470, 500, and 530°C were determined using experimental data. Activation energies for closure of the 1, 6-carbon ring and 1, 5-carbon ring from n-hexane were 180.2 and 111.2kJ/mol, respectively. Using these kinetic parameters, the product distribution for the reaction of C₆ hydrocarbons over Pt/KL could be successfully predicted at various reaction temperatures and pressures.

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Catalytic conversion of light naphtha to aromatics over platinum supported on zeolite L (Pt/KL) was studied using pilot scale units of an externally heated tubular reactor and an adiabatic reactor under operating conditions close to those used for commercial reactors, and simulated using data from laboratory experiments.
Product distributions and temperature profiles in the catalyst bed of the adiabatic reactor and the externally heated tubular reactor agreed fairly well with the simulated values. The simulated performances of the adiabatic reactor and the externally heated tubular reactor were compared, suggesting that the externally heated tubular reactor is more advantageous than the adiabatic reactor, since the operating temperature at the catalyst bed can be lowered, resulting in a slower reaction rate of hydrocracking and a consequent increase in the benzene yield.

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The molten carbonate fuel cell (MCFC) system was applied to a reactor for the selective conversion of methane to produce synthesis gas and C2 compounds (ethane and ethylene). The cell type MCFC reactor was designed for improved stability and shorter pretreatment time. The doctor blade method was effective for the construction of the cell.
The design of the anode catalyst is essential for this reaction. Two types of catalysts were prepared for the MCFC reactor. Li-Ni/Al₂O₃ catalyst was used for producing synthesis gas and La₂O₃ catalyst for C2 compounds. These anode materials selectively produced the required chemicals with corresponding electric power.

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The contamination of soil due to the presence of petroleum hydrocarbons is an important environmental issue. In Australia, there are a number of methods that are employed for such analysis, all of which are widely accepted. In this study, we specifically focused on the sonication and the soxhlet extraction techniques, which are two of the common methods of extracting semi-volatile Total Petroleum Hydrocarbons (TPH). The components that fall within this fraction are the hydrocarbons with their carbon index number ranging between 10 and 36 (i.e. C₁₀ to C₃₆). The C₁₀ to C₃₆ TPH fraction was further broken up into sub-fractions, which were C₁₀-C₁₄, C₁₅-C₂₈ and C₂₉-C₃₆, in order that specific details regarding the extent of the contamination could be assessed. The TPH extractions were carried out on 84 homogenized clay soil samples collected from service station sites. The soils were then classified and confirmed to contain greater than 50% clay in all cases. The moisture content of the soil varied with a minimum of 6.9% and a maximum of 32.7%. These soils were extracted in duplicate by the sonication and the soxhlet extraction techniques. The extracts were analysed by gas chromatography with flame ionisation detection (GCFID). After performing the relevant statistical analysis it was concluded that the soxhlet extraction generated higher semi-volatile TPH concentrations than the sonication extraction technique for the clay soil samples. This variation was significant and therefore should be an important factor to consider since TPH analysis is mostly conducted using the sonication extraction technique.

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The effects of Ce additive on CO₂ hydrogenation over Rh/SiO₂ catalysts were studied. Ce addition drastically increased CO₂ conversion. The main product was CO over unpromoted Rh/SiO₂ catalyst, but methane over Ce promoted Rh/SiO₂ catalyst. Moreover, Ce additive promoted ethanol production. The mechanism of the promotion effect of Ce was investigated by XRD, TEM, EDX and FT-IR. The mean metal particle size of Rh-Ce/SiO₂ estimated by XRD and TEM analysis was smaller than that for Rh/SiO₂ and Ce/SiO₂. In-situ FT-IR during reaction and CO₂ adsorption on unpromoted catalyst showed CO₂ molecules were adsorbed as CO species as found in CO adsorption. However, a new peak attributed to carboxylate species was observed at around 1570cm^-1 by CO₂ adsorption as well as during reaction over the Ce promoted Rh/SiO₂ catalyst. This result indicates that the Ce additive enhanced CO₂ adsorption on the catalyst, leading to increased activity. The new adsorption band at around 1700cm^-1 may be attributed to a CO molecule bonded through both the carbon and oxygen atoms due to higher metal dispersion. These findings suggest that the Ce additive enhanced CO dissociation and CO insertion over Rh/SiO₂ catalysts, resulting in promotion of CH₄ and ethanol formation.

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The homogeneous oxidation of isopentane was investigated in the vapor phase. The main products were oxygenated compounds (3-methyltetrahydrofuran, 2-propyloxirane, 2-ethyl-2-methyloxirane, 2, 2, 3-trimethyloxirane, acetone and acetaldehyde) and isopentenes. The yields of oxygenated compounds and isopentenes depended on the residence time, indicating that the oxygenated compounds formed through isopentenes from isopentane. It is concluded from the results of the vapor-phase oxidation of isopentenes (3-methyl-1-butene, 2-methyl-2-butene and 2-methyl-1-butene) that 3-methyltetrahydrofuran and 2-propyloxirane might be formed through 3-methyl-1-butene, 2, 2, 3-trimethyloxirane and acetone through 2-methyl-2-butene, and 2-ethyl-2-methyloxirane through 2-methyl-1-butene in the vapor-phase oxidation of isopentane.

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Supercritical water liquefaction of scrap tire rubber and Ishikari coal, separately and in mixtures was investigated to study the possible synergetic effects of coliquefaction between the feedstocks. The effects of partial oxidation on the liquefaction characteristics caused by the water-gas shift reaction in supercritical water were also investigated. Liquefaction was carried out in a tube-bomb reactor at 673K and 25MPa, in the presence and absence of Ni catalyst. The Ni catalyst increased the content of H₂ and decreased the content of CO in the gas product for both separate and mixture liquefaction, indicating that the water-gas shift reaction was increased by the Ni catalyst. Carbon conversion for coal-tire coliquefaction was greater than the average of the separate conversions, especially when using the Ni catalyst.

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Immiscible binary liquid mixtures consisting of methanol and diesel fuel, soybean oil, or rapeseed oil were homogenized by addition of methyl t-butyl ether, ethyl t-butyl ether, t-amyl methyl ether, tetrahydrofuran, tetrahydropyran, or 1, 4-dioxane. Liquid-liquid solubility curves for the ternary systems of ether, methanol, and oil were obtained at 298.15K. The ignition behaviors were further observed for ether/alcohol/diesel fuel mixtures. Tetrahydrofuran mixtures had the best characteristics for use as alternative fuels in diesel engines.

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Ethanol production from sweet sorghum in China was investigated for three cases: 1. Conventional fermentation, 2. Fast fermentation, and 3. Fast fermentation with hydrothermal hydrolysis of horocellulose. Sweet sorghum production in the present corn field in Jilin province will produce 7.1 times as much energy as gasoline used in Shanghai. Fast fermentation is effective for reducing cost of ethanol production. Hydrothermal hydrolysis further reduces the cost by increasing the amount of ethanol production.

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The ignition qualities of LPG with liquid hydrocarbons and a cetane improver were investigated. As a result, the cetane improver improved the ignition qualities of LPG fuels with liquid hydrocarbons more effectively than that of LPG alone. Also, LPG with 30wt% of some liquid hydrocarbons and 1wt% of a cetane improver showed an equivalent ignition quality to that of commercial diesel fuel.

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