In this paper, results from an experimental investigation of carbon dioxide (CO 2 ) solubility and diffusivity in the ionic liquids 1-n-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([bmim], and 1-n-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF 4 ]) are reported. A transient thin liquid film method was developed, which enables one to determine the Henry's law constant and the diffusivity at low pressure simultaneously. Measurements were performed at temperatures in the range of 283-323 K. Henry's law constants were in the range of 25.5-84 bar and were in general agreement with measurements reported by other researchers for these and similar ionic liquids. The entropies and enthalpies of absorption were determined to increase as gas solubility decreased. The measured CO 2 diffusion coefficients in the five ionic liquids were ∼10 -6 cm 2 /s, which is an order of magnitude smaller than the coefficients for CO 2 diffusion in traditional organic solvents. In contrast to the gas solubility results, measured diffusion coefficients were determined to be dependent on the ionic liquid cation as well as the anion. In addition, CO 2 diffusion coefficients were considerably more sensitive to temperature than were CO 2 solubilities in these ionic liquids. Results were used to develop a correlation relating CO 2 diffusion to ionic liquid properties and system temperature.

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High-density fuel was prepared by catalytic dimerization and subsequent hydrogenation. Different amounts of phosphotungstic acid (H 3 PW 12 O 40 , HPW) were loaded on mesoporous silica (SBA-15) by a simple impregnation method to prepare HPW/ SBA-15 catalysts. The prepared catalysts were mesoporous. Characterizations indicated that the dispersion and the specific surface area depend on the HPW amount. The obtained dimers from catalytic dimerization of b-pinene underwent isomerization and then dimerized to form the heterogeneous products. At the optimum load of HPW, the HPW/SBA-15 catalyst displayed the highest catalytic activity and the increased yield of dimer for a 3-h reaction. After the subsequent hydrogenation reaction, the obtained hydrogenated dimer products displayed a density and a volume calorific value comparable to those of commercial JP-10.

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Immobilization of the bacterium Agrobacterium tumefaciens UP-3, which was isolated from soil and sewage in the Shengli Oilfield, was studied in this paper. The suitable culture condition of growth cells was determined. The effects of immobilization conditions and materials on the desulfurization performance of immobilized cells were investigated. The results showed that the immobilized cells with mixture of sodium alginate (SA) and polyvinyl alcohol (PVA) as the immobilized carrier had good biodesulfurization characteristics; The optimum operation immobilization conditions are 4° C, the concentration of SA being 3% (w), the concentration of PVA and SA being 7% (w), and the ratio of carriers (ml) and cells (g) being 20. When DBT addition is 2.7 mM, the DBT degradation rate of immbobilized cells is above 60%.