This paper describes a series of experiments relevant to the screening of microbes to adapt and monitor the targeted microbes in the microbial enhanced oil recovery (MEOR) process. Firstly, the samples of reservoir brine, soil of well site, drilling cuttings, and activated sludge were collected from domestic oil fields, drilling sites, sewage treatment facilities, and environmental conditions. To achieve higher oil recovery, metabolic products of isolates were individually evaluated. These isolates were also incubated in culture bottles packed with silica sands, to clarify the growth potential and metabolic activity in the micro culture space. By carrying out two stages of flooding experiments simulating the reservoir environment, the capability of isolates for improving oil recovery was evaluated, and the microbes were selected.
Two gene-engineering techniques were established in parallel with the screening experiments for monitoring the microbes injected into the reservoir. These techniques are potentially capable of rapidly detecting the presence of injecting microbes; moreover, they are available and effective for studying the microbes relevant to the MEOR process. In addition, it was demonstrated that metabolic activity of the microbes capable of producing effective gas could be estimated based on the quantity of 2, 3-butanediol found as a major end product of fermentation. The results of the huff & puff field test implied that the gene-engineering techniques established in this study and the metabolic activity analysis on 2, 3-butanediol were effective for understanding the growth and metabolic activity of the microbes injected into the reservoir.

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Catalysts for conventional hydrodesulfurization (HDS) were evaluated for use in effective ultra-deep HDS (UD-HDS) of JIS No. 1 kerosene to attain sulfur content of 0.1 wt ppm maximum under below 1MPaG. Analysis of the JIS No. 1 kerosene showed a wide sulfur distribution consisting light to heavy sulfur compounds. Then, the original reaction order of kerosene, n=1.3 in the refinery, changed to n=2.0. A concentrated Ni-Mo/Al₂O₃ catalyst for petroleum middle distillates was selected as one of active parts of a combined catalyst for large phosphoric acid fuel cell (PAFC). A tailor-made Ni-Mo/Al₂O₃ catalyst that was improved to meet the HDS of the large sulfur compounds proved to clear the target. To keep the activity of Ni-Mo/Al₂O₃ catalysts, a recycling procedure of H₂S became necessary, which may be difficult in a small PAFC package. An adsorptive HDS using a conventional HDS catalyst without pre-sulfurization was more active than the usual HDS using the presulfurized catalysts. The catalyst, however, could not realize the target. On the contrary, an adsorptive HDS using a reduced Ni catalyst was most active in this study. The life of the reduced Ni catalyst is short for a practical long operation. However, the catalyst showed a possibility to develop a new Ni catalyst, and seemed hopeful for a large PAFC combining with the conventional concentrated Ni-Mo/Al₂O₃ catalyst. Further, in the sensitive UD-HDS experiment, some poisonous compounds from the caulking of the metallic cans were found.

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An idea to regenerate sulfur-poisoned Ni catalyst in flowing H₂ was tried. That is, sulfur-poisoned Ni catalyst particles are mixed with ZnO fine particles in a H₂ atmosphere at 600K, then the each poisoned catalyst particle would releases a few ppb of H₂S through the H₂ atmosphere and the released H₂S would be accepted on neighboring ZnO particles. Then, a million-fold effective improvement in the regeneration of sulfur-poisoned Ni catalyst in a flow of H₂ would be realized. After only a 90h of trial operation, sulfur-poisoned 60% Ni/Al₂O₃ catalyst was regenerated. Applying this idea, 12.3% Ni/ZnO was prepared and tested as a model catalyst for adsorptive ultra-deep hydrodesulfurization (UD-HDS) of kerosene in a stream of H₂ containing 25% CO₂ at 600K. Residual sulfur in the treated kerosene was not detectable (<0.06 wt ppm) by the ready-made sensitive sulfur analyzer even after 800h of operation. Comparing with the conventional Ni/Al₂O₃ catalyst, the Ni/ZnO catalyst did not produce any CH₄. The ZnO support is regarded to serve as a kind of SMSI and to regenerate Ni catalyst automatically in the HDS. To the best of our knowledge, this is the first time that the regeneration of the sulfur-poisoned Ni catalyst in a H₂ stream was realized and the automatic regenerative Ni catalyst for adsorptive HDS was demonstrated. Other materials for the catalyst of adsorptive UD-HDS were investigated. Al₂O₃ and Fe₂O₃ were useful as sub-materials, however, Cu, Co, Mo, Pd, and Pt were not comparable to Ni and ZnO.

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The state of water clusters of dissolved with distilled water (DW), hydrochrolic acid (WHCl), and potassium hydroxide (WKOH) in hydrocarbons such as n-Tetradecane (TD), Liquid paraffins (LPs), and Polybutadiene (PB) was analyzed by FT-IR spectroscopy at 20°C. The amount of water dissolved with DW in TD, LPs, and PB increased in the following order: TD<LPs<PB. In TD, LPs, and PB, the amount of water dissolved with DW, WHCl, and WKOH increased in the following order: DW<WKOH<WHCl. The number of clusters in TD, in LPs, and in PB increased in the following order: DW<WKOH<WHCl. The solubility of WHCl and WKOH in PB is incresed by the interaction between the double bond of PB and the coexised ions in the dissolved water.

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The amination of 1-bromobutane in an aqueous ammonia solution of 50wt% ammonia using a high-pressure coiled-tube flow reactor was examined. The temperature range studied was from 343 to 403K and the reaction pressure was 13MPa. The major reaction products were n-butylamine and di-n-butylamine, but higher amines, such as tri-n-butylamine, were detected only in trace amounts. Based on a second order consecutive reaction model for the formation of n-butylamine and di-n-butylamine, the reaction rate of amination of 1-bromobutane was determined. Arrhenius parameters for the rate constant of the first reaction step to form n-butylamine were found to have an activation energy of 87.9kJ/mol and pre-exponential factor of 1.03×10⁹mol/(dm³ s), and those for the second reaction step to form di-n-butylamine were found to have the activation energy of 84.3kJ/mol and pre-exponential factor of 4.30×10⁹mol/(dm³ s).

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Supporting platinum on alumina solid Lewis superacid (AmLSA; J. C. S., Chem. Commun., 645 (1989)) was prepared by using of the in situ CVD technique at 773K with Ar⁺-sputtered platinum fine particles and dry chlorine, followed by reduction with hydrogen at 673K. The AmLSA-supported platinum catalyst (Pt/AmLSA) was applied to isopropylation of benzene with propene in the hydrogen stream at ambient temperature, using a semi-batch reactor. Products were mono-, di-, tri-, and tetra-isopropylbenzenes. Conversion of propene to propane was below 1%, and a trace amount of cyclohexane from benzene was also observed. Deactivation of AmLSA due to strong adsorption of poly-substituted benzenes and/or propene oligomers was remarkably depressed by supporting platinum and supplying hydrogen into the propene stream. Consequently, the activity of Pt/AmLSA catalyst had increased almost 1.5 times that of AmLSA. At the same level of benzene conversion, the product distribution of isopropyl-substituted benzenes obtained on Pt/AmLSA was identical to that on AmLSA, and had shifted slightly into the mono-substituted benzene side compared with the result on AmLSA in the absence of hydrogen. In the isopropylation of benzene with 2-chloropropane, the results quite similar to those described above were obtained. From the above observations, synergetic effects of platinum supporting and hydrogen supplying were considered to be due to the presence of hydrogen atoms spilled over from the platinum surface to the strong Lewis acid sites.

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Experimental approaches were made to investigate the deposition of oil mist from horizontal turbulent pipe flow in the presence of liquid film flow. 1-Dodecane mist having mass median diameter of 1.7μm, with geometric standard deviation 1.35, are used in air flows which Reynolds numbers are controlled at selected values between 3700 and 8300. Measurements are made for the deposition flux, pressure drop and liquid film velocity at gas-liquid interface. The observed deposition velocities are affected by concentrations of oil mist, friction velocities and velocities of liquid film. The observed data for deposition velocity are compared with the previous results for the deposition of aerosol particles in horizontal and vertical turbulent pipe flows, and shows a lager value compared to the previous ones. A new correlation is proposed for the deposition velocity of oil mist from horizontal turbulent pipe flow in the presence of liquid film flow.

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Molecular weight distribution measurements of asphaltenes in five types of petroleum vacuum residues (VR) were performed by laser desorption ionization mass spectroscopy (LDI-MS).
The mass spectrum was obtained by optimizing the contents of the solution and laser power. For Arabian Heavy-VR (AH-VR) asphaltene, its mass spectrum showed a large peak up to m/z 6000 with a bi-modal profile, that is, a small peak near m/z 400 and a large and broad peak near m/z 1500 for the others. Similar distribution profiles were obtained for those in another type of VR. The average molecular weight obtained by mass spectrum was always smaller than that obtained by vapor pressure osmometry or by gel permeation chromatography.
The mass spectra for the three fractions, saturate, aromatic, and resin, separated from maltene in AH-VR were also obtained. The mass range of the smaller peak at near m/z 400 for the asphaltene was almost the same as that of aromatic and/or resin in the maltene.
Based on the mass spectra of four fractions separated by solvent extraction and GPC for AH-VR asphaltene, the peak near m/z 400 would correspond to some components in the resin drawn at the solvent extraction.
By increasing the laser power of LDI-MS for AH-VR asphaltene, sharp homogeneous peaks classified in different types of aromatic hydrocarbons were observed at the interval of m/z 24 over a range from 700 to 5000, accompanied with many fragmentary peaks. It suggests that AH-VR asphaltene consists of various groups of homologous derivatives attached to a given condensed aromatic ring system.
Although similar periodic peaks for SL-VR to those for AH-VR are observed, a different distribution was shown by group analysis. The LDI-MS is applicable to characterization and structural analysis of asphaltene.

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Palladium acetate was supported on polyorganosiloxane bearing phosphine group, as a catalyst for hydrogenation. The catalytic hydrogenation of cyclohexene and nitrobenzene over the inorganic polymer-supported Pd complexes in the presence of hydrogen, pressure 1atm, at 25°C, was investigated. Polyorganosiloxane (POS)-supported Pd catalyst with 7.36 of P/Pd, which indicates mole ratio of the phosphine group on POS to palladium, revealed maximum catalytic activity for both substrates, when the ratio of P/Pd in the catalyst was changed from 3.84 to 27.94. The activity of POS-supported catalyst with a variety of P/Pd ratios for both substrates increased, in the following order: P/Pd=7.36> 14.50>3.84>27.94. These results suggested that catalytically active species on POS-supported Pd complexes for both substrates are the same. It seems that reactivities of supported Pd complexes reflect the amount of coodinatively unsaturated (and catalytically active) species, following the above order.
Effect of solvent on hydrogenation reaction of cyclohexene and nitrobenzene with the catalysts was also evaluated. As the relative permittivity (ε_r) of solvent increased, the activity usually increased for both substrates. For DMF and DMSO, the activity, however, decreased as ε_r increased. Effects of solvent on catalytic hydrogenation system was expressed by relative permittivity (ε_r), E_T(30)-parameter, and cation-solvating tendencys (B) of solvents and substrates.

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In order to clarify the effectiveness of the Ni/Ca/carbon catalyst/Ag-Pd membrane-type reactor (PMR) system on decomposition of hydrocarbons such as ethane and gasoline, the decomposition of these hydrocarbons was investigated. The combined system was found to be more effective for hydrogen production at 550-750K than the fixed-bed reactor (FBR) system. In fact, the use of PMR resulted in the formation of a smaller amount of methane (<10% yield) as a major by-product than that in the FBR (10-50% yield). It could be postulated because, first, the direct decomposition of ethane to form hydrogen in the PMR system occurs predominantly by ethane cracking to give methane, carbon, and hydrogen and, second, the permeation of hydrogen prevents recombination of hydrogen with the carbon products to give methane. The Ni/Ca/C catalysts/PMR system was found also to be effective for the formation of hydrogen by decomposition of commercially available gasoline at temperature as low as 573K.

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Selective catalytic reduction of NO_x was performed under the condition of Japan diesel 13-mode cycle over a Co-alumina catalyst using a light oil as reducing agent. The reaction temperature of the NO_x reduction in each mode was sat at that of the exhaust gas. The adsorption of NO_x on Co-alumina was observed under low load conditions, that is. NO_x was adsorbed on Co-alumina when the exhaust gas temperature was below 250°C. However, when the temperature was above 300°C, NO_x conversion increased with increased intensity of reaction, and at near 550°C, it attained its maximum value. The decrease in NO_x conversion was observed at 90% oxidation of the light oil. The result of such temperature dependence of NO_x conversion was compatible with our previous result. The NO_x mass emission from the diesel engine tested was 6.5g•kW^-1•h^-1 under Japan diesel 13-mode cycle, assuming that all NO_x in the exhaust was NO₂. The NO_x mass emission was 4.4g•kW^-1•h^-1 when the Co-alumina catalyst was used. The decrease in NO_x mass emission by use of the catalyst resulted in NO_x reduction at medium to high load modes and NO_x adsorption at low load modes. When the NO_x conversion was assumed to be 0% at low load modes (1-5 and 13 modes) over the Co-alumina catalyst saturated with adsorption of NO_x, the NO_x mass emission was 4.7g•kW^-1•h^-1.

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