Effective and Reusable Oxidative Desulfurization of Dibenzothiophene via Magnetic Amino-MIL-101 Supported H₃PMo₆W₆O₄₀ Components: Comparison Influence on Various Types of MIL-101

Abstract

Different metal–organic frameworks, MIL-101(Al) and MIL-101(Fe), were compared to use in fixing active components H3PMo6W6O40 (abbreviated as POM in this work), and Fe3O4 was also introduced to endow them with magnetic properties, namely, the final catalysts as Fe3O4@NH2-MIL-101-POM (abbreviated as Fe@NH2-MIL-101-POM). Their characterization was assessed by FT-IR, XRD, BET, SEM, and vibrating sample magnetometer analyses, mainly discussing the comparison of different MIL-101 materials in the system. Under the oxygen in air as the oxidant, both catalysts were used in the oxidative desulfurization process to remove dibenzothiophene (DBT). Moreover, POMs loading amount, catalyst amount, reaction temperature, air flow rate, and agitation rate were also compared to study for optimal reaction conditions. Remarkably, Fe@NH2-MIL-101(Fe)-POM showed an excellent conversion (100%) in 60 min with a lesser catalyst amount and more recycling times. The results could be attributed to the larger surface area of MIL-101(Fe), leading to attachment with more active components, which could provide more contact opportunity with DBT under air. This finding shed new light on the MIL-101(Fe) materials in the oxidative desulfurization process as an effective supporter to fix other active components in the future.