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The desulfurization of non-hydrotreated gas oil using oxidation followed by liquid/liquid extraction has been studied. The solvent extraction of oxidized sulfur- containing compounds of gas oil was carried out by utilizing various types of solvents, including acetonitrile, methanol, and 96 vol.-% ethanol. The performance of these solvents was carefully evaluated and compared by considering both desulfurization and gas oil recovery. It was found that their performance follows the order: acetonitrile > methanol > 96 vol.-% ethanol. The influences of operating conditions, such as number of extraction stages and solvent to gas oil ratio, on the desulfurization and recovery of gas oil, were... 

A crude phenolic glycolipid extract from Mycobacterium bovis BCG was fractionated by column chromatography. A reversed-phase high performance liquid chromatography (HPLC) method with UV detection at 275nm was developed for simultaneous detection and separation of phenolic glycolipids (PGLs) in Mycobacterium bovis BCG. This analysis provides a good resolution. Different solvent systems and columns for HPLC were compared. A system composed of acetonitrile-water in the ratio of 0→80% at a flow rate of 0.8 mL/min and C8 analytical column were found to be optimum for HPLC of the phenolic glycolipids. This simple method is therefore appropriate to purify these compounds present in M. bovis extract... 

Oxygen evolution was observed upon mixing solid manganese(III) bidentate Schiff base complexes with aqueous solutions of cerium(IV) ammonium nitrate. However, oxygen evolution was not observed upon mixing solutions of the complexes (in acetonitrile) with Ce(IV). Electron-withdrawing substituents on the Schiff base ligands (NO2, Br) enhanced the reactivity of the manganese complexes toward oxygen evolution. Oxygen evolution was also affected by R groups on the ligands, in the order Me > Et Bz. © 2009 Springer Science+Business Media B.V  

The catalytic activity of highvalent iron-oxo active species of heme enzymes is known to be dependent on the nature of the axial ligand trans to the iron-oxo group. In a similar fashion, experimental studies on iron-oxo porphyrin biomimetic systems have shown a significant axial ligand effect on ethylbenzene hydroxylation, with an axial acetonitrile ligand leading to phenyl hydroxylation products and an axial chloride anion giving predominantly benzyl hydroxylation products. To elucidate the fundamental factors that distinguish this regioselectivity reversal in iron-oxo porphyrin catalysis, we have performed a series of density functional theory calculations on the hydroxylation of... 

Dilatometric measurements of excess molar volumes, VE and excess partial molar volumes, V̄iE have been made for binary mixtures of acetonitrile with 1,2-ethanediol, 1,2-propanediol, 1,2-butanediol, 1,2-pentanediol, and 1,2-hexanediol at 20°C over the entire composition range. VE for acetonitrile + 1,2-ethanediol and 1,2-propanediol mixtures are negative over the entire range of mole fractions and positive values are obtained for all remaining mixtures. The results are explained in terms of dissociation of the self-associated 1,2-alkanediol molecules and the formation of aggregates between unlike molecules through O-H. . . N≡C hydrogen bonding. From the experimental results, VE were...