Oxidative desulfurization of dibenzothiophene with molecular oxygen catalyzed by carbon fiber-supported iron phthalocyanine

Iron tetranitrophthalocyanine (FePc) was modified and immobilized on carbon fiber (FePc(NO 2 ) 3 –CF) by covalent bond to obtain a supported heterogeneous catalyst for the removal of dibenzothiophene (DBT) in tridecane. In the supported catalytic system, the catalyst exhibited an excellent catalytic performance without any sacrificial agents, and the conversion of DBT could reach 92 % at 130 °C and 0.2 MPa of initial dioxygen pressure for 3 h. Compared to unsupported FePc, the introduction of carbon fiber dramatically improved the catalytic activity of FePc and facilitated the reuse of catalysts. The amount of FePc(NO 2 ) 3 –CF, temperature and the initial pressure of molecular oxygen were also studied in detail to optimize the reaction conditions. The removal of DBT significantly increased with the increasing of concentration of DBT in model oil. Finally, a mechanism involving high-valent iron oxo species was proposed for the oxygenation. This study provides new insights into industrial desulfurization systems using carbon fiber as catalyst carrier.