Efficient and rapid removal of thiophene sulfides from fuel using zirconia-loaded phosphotungstic acid

In this study, a new type of composite was synthesized via the sol–gel method. The structure and properties of the composite were analyzed using X-ray diffraction, scanning electron microscopy, nitrogen isothermal adsorption and desorption tests, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Characterization results showed that phosphotungstic acid (PW12) was successfully loaded on zirconium dioxide (ZrO2). The oxidative desulfurization performance of 500 ppm dibenzothiophene (DBT) was studied with H2O2 as the oxidant and xPW12/ZrO2 as the catalyst. Under optimal conditions (T = 60 °C, O/S = 2 and m = 0.03 g), the desulfurization rate reached 97.85% within 20 min, and the activity did not decrease significantly after 8 cycles. The kinetics of the reaction was studied at different temperatures. Results showed that the oxidation rate conforms to quasi-first-order kinetics and the apparent activation energy is 23.32 kJ mol−1. Therefore, the composite material is expected to be a catalyst for oxidative desulfurization.