Prominent Oxidative Desulfurization with an Advanced Colloids Catalyst under Mild Conditions: Synergistic Interaction of Interface-Phase Transfer

Maximizing the mass transfer rate and enhancing the effective spread of active sites and recovery of catalysts between various stages of reaction could help to realize catalytic oxidative performance. Colloidal catalysts can break through the bottleneck problems between solid and liquid catalysts. In this work, colloid Zr-MOFs materials were prepared for the first time as support, and CDUT-Colloid catalysts were prepared by combination with liquid active components. Catalysts exhibit efficient mass transfer characteristics and high dispersion of active sites characteristic of ILs, while possessing the advantages of easy recovery and high stability. The oxidative desulfurization performance approaches 100% under mild reaction conditions (m(CDUT-Colloid-2) = 0.5 g, t = 90 min, n(O)/n(S) = 10, 30 °C). This catalyst exhibits excellent recycling performance, stability of structure, absorbability, and suitable viscosity. The proper viscosity of the colloidal catalyst facilitates phase transfer at the interface, accelerating the transfer of sulfide from the oil phase to the colloidal phase. The phase interface after the reaction is easy to separate, ensuring purity of the final oil. Based on structural analysis, desulfurization performance, and the capture experiment of the transition state (•OH), the oxidative desulfurization reaction mechanism of the colloidal catalytic system can be obtained. The catalytic reaction mechanism can be divided into two steps of collaborative catalysis, which can reveal the uniqueness of the colloidal catalyst in the reaction process. This unique colloidal catalyst provides a research approach for catalysts and lays the foundation for the study of functional materials.