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

•The dimeric μ-oxodiiron(III) porphyrin (μ-O(FeTPFPP)2)was synthesized.•μ-O(FeTPFPP)2 showed to be an efficient catalyst for oxidative desulfurization.•A model oil free of refractory sulfur compounds in fuel was achieved after 2 h.•μ-O(FeTPFPP)2 showed a remarkable catalytic performance to benzothiophene oxidation.•The porphyrin could be reused in consecutive desulfurization cycles.

The present work is the first report of using a FeIII 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 μ-oxodiiron(III) complex of meso-tetrakis(pentafluorophenyl)porphyrin μ-O(FeTPFPP)2, was synthesized and characterized by UV/Vis spectroscopy, mass spectrometry and single-crystal X-ray diffraction. μ-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.

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