Light (LGO) and heavy or vacuum gas oil (VGO) fractions from mixed Middle East crudes and respective fractions from a typical Canadian oil sands bitumen-derived synthetic crude oil (SCO) were blended at various ratios (up to 40%) and hydrotreated to investigate the kinetics of sulfur and nitrogen removal, and product quality. Hydrotreatment was carried out in down-flow micro reactors over commercially available NiMo/Al₂O₃ and CoMo/Al₂O₃ catalysts, varying reactor temperature (350-390°C), pressure (5-10 MPa), and space velocity (1-6 h⁻¹). Blending the LGO with SCO enhanced both sulfur and nitrogen removal from Middle East crude LGOs. Ultra-low sulfur diesel (< 10 wtppm) meeting the Japanese cetane number (CN) specification could be produced under reasonable operating conditions. Engine tests of the hydrotreated LGOs showed that the emissions of CO, HC, NO_x, and PM (particulate matters) from a diesel engine were correlated with the fuel CN and aromatics content. Hydrotreatment of blends of VGO and SCO led to lower sulfur content, but higher nitrogen content in the product oils. The estimated yields of FCC gasoline were slightly decreased by blending the SCO but not significantly.

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The kinetics of oxidative coupling of methane reaction over a Na/BaTiO₃/MgO catalyst was studied under differential conditions in a fixed bed flow reactor. The experiments were carried out at 725, 775 and 825°C. Methane and oxygen partial pressures in the reactor were varied from 0.05 to 0.92 and 0.05 to 0.17 atm respectively with the total pressure of 1 atm for all reactions. Using molecular point of view the semi-mechanistic reaction rate equations for C₂H₆ (ethane) formation and CH₄ (methane) conversion rates have been proposed. The approximate total carbon oxides formation rates have also been deduced intuitively. The parameter 'n' was introduced that shows the portion of the reaction, which produces carbon oxides. After investigating some mechanistic approaches one of them was selected as the best mechanism.

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To clarify the effect of sulfur compound addition on catalytic activity and catalyst deactivation, hydrodesulfurization (HDS) of coker gas oil (CGO) was carried out over demetallation catalysts, metal tolerant desulfurization catalyst and desulfurization catalysts. The initial HDS constant and catalyst life were slightly improved by the addition of 1000 ppm of dimethyldisulfide (DMDS), probably by the prevention of coking on the catalyst surface. The CH₃S radical formed via thermal decomposition was important in the suppression of recombination of heavy hydrocarbon radicals which results in coke or coke precursor formation. The addition of small amounts of sulfur compounds to the CGO is expected to reduce coke formation during the early stages of HDS.

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Bimodal porous catalysts were prepared by modifying the surface of macro-porous silica (Q-10, Q-30 and Q-50) with 20 wt%Co-0.5 wt%Ir-SiO₂ prepared by the alkoxide method, and used for the Fischer-Tropsch synthesis in the slurry phase. The bimodal pore structure was confirmed by the pore size distribution, BET surface area, and pore volume of the catalysts. The bimodal catalysts showed high and stable activity for more than 70 h of the reaction, with reducing the using amounts of expensive alkoxide. The high activity indicates that the surface of the alkoxide catalyst (Co-Ir-SiO₂) efficiently participates in the reaction. The olefin selectivity increased with the macro-pore size of the bimodal catalysts. The higher selectivity was explained in terms of the high diffusivity of products and/or slurry solvent within the macro-pores of the bimodal catalysts. Consequently, an olefin/paraffin ratio of 0.9 in the C₂-C₄ products was obtained over the bimodal catalyst with the composition of [Co-Ir-SiO₂] : [Q-50] = 1 : 3 by weight.

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Water-related damage to bituminous pavement is considered to result from penetration of liquid water from the surface and/or subsurface. However, surface courses made of bituminous material such as runway pavements are usually not permeable for liquid water. Therefore, such phenomena may be caused by moisture vapor in the air. A new moisture permeation test apparatus was developed to analyze the mass transfer. Moisture permeation tests under typical hot summer conditions suggested that atmospheric moisture permeates and accumulates in bituminous mixtures through mass transfer by vapor diffusion despite the water impermeability of bituminous surface mixtures. The moisture permeation test provides an effective approach to analyze water storage mechanisms and moisture-related phenomena such as blistering in bituminous mixtures, although the test apparatus and condition settings require some improvement.

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High precision is essential in the localization of anomalies (laminations, corrugations, corrosion, stress, blows, etc.) by the pig inspection device in any pipeline. The problem of distance measurement accuracy by an odometer inside a pipeline was investigated. The causes of error and the effect on error magnitude were surveyed. Odometer error can be caused by loss of the contact with the internal surface of the pipe. The effects of the odometer bumping into a weld or other mechanical defect in the pipe surface were investigated in detail. A special simulator of odometer wheel movement in a pipe was developed. Simulation of the odometer motion along the surface with joint welds was performed in gas and in fluids of different densities (water and oil) at six different speeds. The test results demonstrate that the distance measuring error of the odometer caused by joint welds depends on the travelling speed of the pig and can be as high as 10%.

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Catalytic features of ruthenium-molybdenum polyoxometalate having a composition of [Ru₂Mo₁₄O₅₀]¹⁰⁻ or [Ru₂Mo₁₄O₅₂]¹⁴⁻ (Ru₂Mo₁₄) were evaluated using liquid-phase selective oxidation of benzyl alcohol with oxygen. Ru₂Mo₁₄ catalyst supported on titania support chemically modified with silane coupling agent that has amino groups (Ru₂Mo₁₄/DAPS-TiO₂) exhibited much higher catalytic activity than other Ru₂Mo₁₄ catalysts unsupported and supported on unmodified titania. Ru₂Mo₁₄/DAPS-TiO₂ exhibited larger turnover frequency than representative polyoxometalates supported on DAPS-TiO₂.

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The addition of small amount of TiO₂ to silica supported cobalt catalysts significantly increased the dispersion of cobalt and Co metallic surface area, resulting in the remarkable enhancement of the Fisher-Tropsch synthesis (FTS) activity in the slurry-phase reaction. The addition of TiO₂ adjusted the interaction between cobalt and silica support quite well, to realize the favorite dispersion and reduction degree of supported cobalt at the same time, leading to high catalytic activity in FTS.

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Wrong:See PDF attached
Right:See PDF attached

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