An efficient eco-sustainable oxidative desulfurization process using μ-oxo-bridged Fe(III) complex of meso-tetrakis(pentafluorophenyl)porphyrin

The present work is the first report of using a Fe-III dimeric porphyrin as an active and efficient catalyst for the oxidative desulfurization of a multicomponent oil formed by the most refractory sulfur compounds in fuels (dibenzothiophene, DBT, 1-benzothiophene, 1-BT, and 4,6-dimethyldibenzothiophene, 4,6-DMDBT), using the biphasic system model oil/extraction solvent. The binuclear mu-oxodiiron(III) complex of meso-tetrakis(pentafluorophenyl)porphyrin mu-O(FeTPFPP)(2), was synthesized and characterized by UV/Vis spectroscopy, mass spectrometry and single-crystal X-ray diffraction. mu-O(FeTPFPP)(2) was shown to achieve a complete desulfurization after 2 h when acetonitrile and methanol were used as extraction solvents, in the presence of a residual amount of H2O2 as oxidant, at room temperature. The catalytic efficiency of the porphyrin was evaluated for each refractory sulfur compound following the order 1-BT>DBT>4,6-DMDBT. Surprisingly, the porphyrin presents a remarkable catalytic performance for the desulfurization of 1-BT when compared with other catalysts already reported in the literature. Furthermore, the extracting phase containing the porphyrin could be reused in consecutive desulfurization cycles. (C) 2014 Elsevier B.V. All rights reserved.