NiMoO ₄ –Fe ₂ O ₃ –BN Nanocomposite for Efficient Ozone‐Assisted Oxidative Desulfurization of Dib

ABSTRACT

In this study, we developed NiMoO ₄ –Fe ₂ O ₃ –boron nitride (BN) nanocomposite as a catalyst for ozone‑assisted oxidative desulfurization (ODS) of DBT and real tire‑derived pyrolysis oil. The characterization analyses confirmed the successful incorporation of crystalline NiMoO ₄ and Fe ₂ O ₃ on BN, a morphological transformation from layered BN to a granular structure with uniformly dispersed 15–20 nm nanoparticles, and an increase in specific surface area from 5.16 to 21.29 m ² g ^{− 1} . In ozone‑assisted ODS of DBT, NiMoO ₄ –Fe ₂ O ₃ –BN achieved a sulfur removal efficiency of 93% under mild conditions (DMF as extractant, neutral pH, 0.1 g catalyst, 10 min ozonation, 25°C), outperforming ozone alone (31%) and bare BN (57%). The enhanced performance is attributed to the synergistic interaction between defect‑rich BN adsorption sites and redox‐active sites of NiMoO ₄ –Fe ₂ O ₃ , which promotes ozone activation, formation of reactive oxygen species, and efficient electrophilic oxygen transfer to DBT. Reusability tests revealed some deactivation upon recycling after high initial stability (93% to 61% DBT removal after five runs) due to partial Fe leaching. Application of the catalyst to pyrolysis oil (initial sulfur 9000 ppm) led to an 83.22% reduction in total sulfur content, demonstrating its practical potential for upgrading high‑sulfur real fuels.