Immobilization of phosphotungstic acid in an amino-containing metal-organic framework for oxidative desulfurization

A composite material has been successfully synthesized using an amino-containing metal-organic framework (NH2-MOF) and phosphotungstic acid (PTA). This composite was characterized using X-ray diffraction, high-resolution transmission electron microscopy, nitrogen adsorption-desorption measurements, Fourier transform infrared spectroscopy and X-ray fluorescence. Characterization results confirmed the immobilization and good distribution of PTA in the NH2-MOF. The PTA/NH2-MOF was subsequently applied in the oxidative desulfurization of dibenzothiophene (DBT) with H2O2 as the oxidant in n-octane under atmospheric conditions. Under optimal reaction conditions, the oxidative desulfurization conversion of DBT reached 100%, and there was no significant decrease of the catalytic activity after four recycles. Kinetic experiments were also performed for the reaction at various temperatures, which indicated that oxidative reaction rates followed pseudo first-order kinetics, and the apparent activation energy for the desulfurization reaction was 34.1kJmol(-1). The results indicated that this material exhibited excellent catalytic performance for oxidative desulfurization of DBT. Copyright (c) 2016 John Wiley & Sons, Ltd.