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Silica-supported vanadium oxides (VxOy-silica 600 °C) and polymer nanofiber [2-(2′-hydroxy-5′-ethenylphenyl)imidazole (PIMv) and styrene (ST) copolymer]-supported oxidovanadium(IV) ([VIVO-p(PIMv-co-ST)]) were synthesized and used as catalysts for the oxidation of refractory organosulfur compounds in fuels in a continuous flow system. Conversion of dibenzothiophene (DBT) to dibenzothiophene sulfone (DBTO2) increased as the flow rate decreased, reaching 100% at flow rates of 0.1 and 0.2 mL/h for (VxOy-silica 600 °C) and [VIVO-p(PIMv-co-ST)], respectively. This was attributed to improved contact time between the catalyst and substrate, which allowed further oxidation to take place. However, the catalytic activity of VxOy-silica 600 °C dropped by 33% after the first oxidation cycle at a flow rate of 0.1 mL/h at 60 °C, unlike [VIVO-p(PIMv-co-ST)], which maintained its activity at 100% after three cycles. Optimized conditions were employed in the oxidation of a hydrotreated fuel sample (Sasol diesel 500) follow...

Ionic liquids containing imidazolium cations 1-butyl-3-methylimidazolium chloride, 1-butyl-3-methylimidazolium nitrate, and 1-methyl-1H-imidazol-3-ium-2-carboxybenzoate were successfully synthesized and employed for the dispersion of asphaltenes in heavy oil, which is becoming a necessity during oil recovery and transportation. Molecular interaction studies indicated that 1-butyl-3-methylimidazolium chloride displayed a small HOMO–LUMO energy gap, which best explains its higher polarizability and reactivity as compared with 1-butyl-3-methylimidazolium nitrate and 1-methyl-1H-imidazol-3-ium-2-carboxybenzoate. Dispersion indices obtained from the experiments were in agreement with the modeling studies. Maximum asphaltene dispersion indices (%) of 78, 70, and 53 were obtained for 1-butyl-3-methylimidazolium chloride,1-butyl-3-methylimidazolium nitrate, and 1-methyl-1H-imidazol-3-ium-2-carboxybenzoate, respectively, when using an ionic liquid-to-asphaltenes molarity ratio of 9:1. The excellent performance dis...

Two synthesized oxovanadium(IV) polymer-supported catalysts, poly[VO(sal-AHBPD)] and poly[VO(allylSB-co-EGDMA)], were employed for the oxidation of thiophene (TH), benzothiophene (BTH), dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT) under a continuous flow system at 40 °C. Maximum conversion was attained at a flow rate of 1 mL/h, with overall conversions of 71%, 89%, 99%, and 88% achieved when poly[VO(allylSB-co-EGDMA)] was employed, and conversions of 79%, 90%, 97%, and 91% were achieved when poly[VO(sal-AHBPD)] was employed for the oxidation of thiophene (TH), benzothiophene (BT), dibenzothiophene (DBT), and 4,6 dimethyldibenzothiophene (4,6-DMDBT), respectively. The high organosulfur oxidation yield displayed by this method, followed by adsorption of the sulfones using chitosan nanofibers, suggests its possible application in the oil industry for oxidative desulfurization (ODS) of hydrotreated fuel.

A majority of chemistry graduates seek employment in a rapidly changing chemical industry. Our attempts to provide the graduates with skills in entrepreneurship and the ability to understand and communicate with their chemical engineering colleagues, in addition to their fundamental knowledge of chemistry, are described. This is done at second-year level with practical projects in which student teams formulate and prepare relatively simple chemical products for marketing, followed a year later by a more advanced study of the feasibility of producing and marketing a fine chemical on a commercial scale.